MultimediaWiki - User contributions [en]

Libav starting tasks

2011-09-04T11:02:15Z

Dark Shikari: /* QA */

Want to get started doing something useful in libav, but not sure where to start? Here's some basic tasks you can do that don't require much detailed knowledge of libav's internals. Need help? Ask on IRC and someone can answer questions and help walk you through your task of choice.

==Task categories==

===QA===

(TODO: make this a bit more detailed so it doesn't require as much searching/knowledge to do.)

Finding bugs in libav is always welcome, and requires little to no knowledge of libav itself. Here's one possible process:

* Make a build of libav with debug symbols.
* Download a sample file from the samples archive.
* Download zzuf and use it to fuzz libav on the file.
* When you find a crash, do a gdb backtrace and report the bug to the libav bug tracker following the bug tracker guidelines.

If a sample file doesn't seem to be giving any crashes, try a different one. Some decoders are more buggy than others.

===Documentation===

==== Low level API ====

==== Tutorials ====

===Coding===

Libav starting tasks

2011-09-04T10:54:03Z

Dark Shikari: initial page

SEVC

2009-06-12T21:40:56Z

Dark Shikari: add alias for EVRC

#REDIRECT [[Enhanced Variable Rate Codec]]

Quotes

2008-12-08T19:09:31Z

Dark Shikari: /* #ffmpeg-devel */

Here are some memorable quotes gathered from various MPlayer and FFmpeg related discussions. Beware of what you say, because it will be recorded, taken out of context and ridiculed!

==IRC Channels==

===#mplayerdev===

<pre>
<ods15> btw, gcc took 900mb of ram and then segfaulted for me when i tried to compile a 30mb C file :P
<ods15> that took about 20 minutes until it evantually gave out of mem error
<ods15> i should probably just write my own compiler than can do it in 0.05s and no ram...
<ShadowJK> can tcc compile it :)
<ods15> ShadowJK, heh i should've tried that
* ods15 just makes a sample file and tries now
<ods15> ahem, it did it in like 3 seconds and no ram :P
</pre>

<pre>
<poirierg> great new ppl! I'm likely to get laid before linuxtag!
<poirierg> woops
<ods15> ...
<poirierg> great new ppl! I'm likely to get laid out before linuxtag!
<dalias> lol poirierg
<poirierg> budget cuts and stuff like that....
<dalias> poirierg, oh
<dalias> i read that as 'get laid'
<dalias> and i was like wtf tmi
<ods15> ja
<dalias> the word is 'laid off' btw, not 'laid out'
<delewis> haha.
<ods15> so, wait, great?
<poirierg> okay, I'm getting laid off
</pre>

<pre>
<ods15> british is american with a sloppy accent, and much stupider curse words
</pre>

<pre>
<poirierg> cartman, you don't see smart girls if you only watch pr0n
</pre>

<pre>
<superdump> Welcome to ye Olde #mplayerdev Tavern. If yaoi 'n' free cola is what ye be lookin' far, we's got 'em! Yarr...
</pre>

<pre>
<dalias> because you can't use x264
<superdump> why not?
<dalias> because the decoder is slower than gabu trying to get a girlfriend
</pre>

<pre>
<dalias> h264 is like matroska
<dalias> yes mmatroska is better than avi but it sucks still
<dalias> hes h264 compresses better than mpeg4 but it sucks still
<dalias> and the question is: is 15% compression gain worth 500% performance drop?
</pre>

<pre>
<poirierg> do you know the difference between God and dalias ? ;)
<dalias> god only tells you what's bad to do when you inhale from a burning bush
<dalias> dalias tells you what's bad all the time
</pre>

<pre>
<reynaldo> i was once atacked by one of those beast
<reynaldo> i was 4 years old iirc
<reynaldo> those birds have almost 4 meters measured from the extremes of their wings
<reynaldo> i have some stories you wouldnt believe :P
<reynaldo> i dont remember meeting any chilean atacked by a condor besides me
<reynaldo> :P
<reynaldo> i was once biten by a black widow too :P extremely hard to find spider
<reynaldo> nature has been trying to kill me since the day i born!
<reynaldo> :P
<iive> i though condors doesn't attack humans.
<reynaldo> they dont
<reynaldo> thats the weirdest part
<reynaldo> :P
<iive> well, then there is only one explanetion. you are not human.
* iive runs
<reynaldo> :P
<reynaldo> who knows
<reynaldo> maybe the karaoke filter is just the begining of my world domination plan
</pre>

<pre>
<reynaldo> why dont you work with me improving the filter then ?
<poirierg> reynaldo, because I don't want to steel the paternity of your little toy
<reynaldo> thats not my boy
<reynaldo> everyone an his girlfriend facing the same problem solved it the same wahy
<reynaldo> we can make something neater
<reynaldo> :)
<poirierg> your are calling me to become the girlfriend of you audio filter?
</pre>

<pre>
<ods15> i'm waiting for someone to send me brains tommorrow, not much to do until then
</pre>

<pre>
<snacky> h264-in-mpeg is standardized since 2003. if hd-dvd does it differently it's because they're stupid ;)
<iive> they do. thay are
</pre>

<pre>
<KotH> Rathann: some nice quotes you have there :)
<Rathann> I know! ^_^
<Rathann> I've been collecting them for months
<KotH> and some i dont even remember typing ^^'
<Rathann> ^_^v
<Rathann> hehe
<Rathann> it's good to have logs
</pre>

<pre>
<phcoder> compiling svn:
<phcoder> allcodecs.c: In function 'avcodec_register_all':
<phcoder> allcodecs.c:67: error: 'ENABLE_DCA_DECODER' undeclared (first use in this function)
<phcoder> allcodecs.c:67: error: (Each undeclared identifier is reported only once
<phcoder> allcodecs.c:67: error: for each function it appears in.)
<phcoder> allcodecs.c:253: error: 'ENABLE_DCA_PARSER' undeclared (first use in this function)
<phcoder> Sorry forgot to configure
<KotH> dont forget make distclean
<Rathann> don't forget to use your brain
</pre>

<pre>
<DonDiego> geez
<DonDiego> how many mistakes can you make in a single line of shell ..
<KotH> one per character
<DonDiego> i'm quite close ;)
<DonDiego> sundays after parties are not the best days for programming ;)
</pre>

<pre>
<cartman> <poirierg> cartman, you don't see smart girls if you only watch pr0n
<dalias> :)
<cartman> this is all I get for reporting quality pr0n bugs
<dalias> cartman, it's what you get for making statements about girls being stupid
<cartman> dalias: girls are stupid anyway
</pre>

<pre>
<ShadowJK> "I have to agree with Rich's supposed opinion here. It is beyond mad."
<ShadowJK> dalias, you've become quite efficient at flamewars, when you don't even need
to participate anymore, people just assume what you were going to say :)
</pre>

<pre>
<iive> btw does somebody know a way to get the xvid bitstream syntax number
<iive> the number that xvid put to identify what bugs they had when encoding it.
<Rathann> rtfs?
<iive> i ask if somebody knows
<iive> this is if nobody knows
<iive> fucker
<rxt> hehe, nothing changed on mplayer while I was away :)
</pre>

<pre>
<snacky> ugh... you guys should see how polite superdump is being to lusers on #ffmpeg . it's really disgusting
<superdump> :)
<snacky> what is it with polite people?! don't you realize you are making the rest of us look bad?
</pre>

<pre>
<KotH> i talked with an ubuntu guy here
<KotH> and the biggest problem they have is that upstream is uncooperative
<Rathann> is it?
<KotH> from their perspective yes
<Rathann> I haven't seen any patches from anyone @ubuntu
<Rathann> nor bugreports, for that matter
<KotH> well, replace upstream by downstream and you get the same in green
</pre>

<pre>
<KotH> the biggest outcome of a 2h+ discussion was that both sites want to work with each other, but think it's impossible
<Rathann> why do they think we're uncooperative?
<Rathann> (obviously we aren't)
<KotH> well... have a look at our history
<ShadowJK> Obviously uncooperative. Refusing to integrate with gstreamer, copying libraries
randomly into source tree, breaking compilation with gcc2.96 on purpose, stuff doesn't compile with PIC, etc etc ;)
<KotH> yeah.. these points come into play too
<KotH> but that's a longer story
...
<ShadowJK> You know, I don't think those MPlayer developers even go to church of Xiph every
week to worship a speedy emergence of Tarkin and ogm as the world dominating system
</pre>

<pre>
<KotH> anyone here who has an understanding of x11?
<ods15> it shows graphics :P
<KotH> yeah, right
</pre>

<pre>
<uau> i was already a better coder than most existing developers when i got involved with mplayer
</pre>

<pre>
<snacky> you guys and your secrets
<KotH> there are more secrets around mplayer than you could possibly imagine
<KotH> like, is there really a michael niedermayer? and if he exists, is he a single entity? is he alien?
<snacky> I wonder if he/they/it has/have any spies in here.
* KotH whistels
* Rathann checks if his tinfoil hat is in place
</pre>

<pre>
<xiphmont_> Vorbis still stands up nicely. Theora, OTOH, is a a bit embarrassing.
* dalias tries to be polite about theora..
<xiphmont_> rather, it's a bit embarrassing until you look at the code, then it's alot embarrassing.
<xiphmont_> and that's 70% 'really fucking stupid encoder, really On2, be ashamed' and 40% 'format
design flaws'. It's so bad it adds up to 110%.
<xiphmont_> I plan to help Theora limp along not too embarrassingly until it can be replaced for
real-- possibly 2-4 years.
<xiphmont_> Theora is actually fixable tho. The amount of low-hanging fruit is staggering.
<xiphmont_> I mean, an entropy backend that results in *more* bits being written than went in? It's
just... wow.
</pre>

<pre>
<|Bio|> but i need fix fo win
<iive> how much do you need it?
<|Bio|> very much.
<iive> as i said, it is not really mplayer problem, mingw is the support library, it should take the ucs2 convert it to utf8 then do the opposite.
<iive> and, very much is not enough.
</pre>

<pre>
<@beastd> hallo iive
<@iive> hi beastd
<@beastd> and what's up with you these times, ivan?
<@iive> nothing much, flaming diego mostly
</pre>

<pre>
<KotH> video player development is anime driven anyways...
</pre>

<pre>
<KotH> damn... now i know again, why i keep that much stone age scsi hardware around
<KotH> if everything else fails...scsi will always boot
<iive> :O
<KotH> i dont think i had that much problems booting a pc since i got that toshiba laptop with non-standard floppy working
</pre>

===#mplayer===

<pre>
* KotH wants a point and click solution... w/o the click
</pre>

<pre>
<Micksa> I'm reading about motion compensation
<Micksa> some of this is serious voodoo
<Micksa> I love it :)
</pre>

<pre>
<dtm> you're a free software pimp, Commn
</pre>

<pre>
<Jan_> mplayer has a number of command line options that is large enough to overflow a 32-bit variable.
</pre>

<pre>
<iive> Commn: yeh.. usa people usually have problem with foregin languages like british, australian or canadian. :)
</pre>

<pre>
<CarlFK> how many gig is an hour of raw DV ?
<DogBoy> like from a porno?
<CarlFK> right
<DogBoy> just how raw are we talking
<CarlFK> right from the cam corder's firewire
</pre>

<pre>
<dtm> Commn: i read all of your wiki page and you forgot the final entry for "and seek professional
help immediately for the mental illness that either
1) made you want to follow all these steps for lazy, codependent fools on irc or
2) that you WILL HAVE after faithfully trying to implement all these steps for a week"
<dtm> http://mfrost.typepad.com/photos/uncategorized/gaaallllgh.jpg that big dog is the cumulative laziness of a lot
of irc users the medium sized cat is Commn and the one watching, frozen in horror, is me
<dtm> now is that a normal response for a cat who has a self preservation instinct? i think not.
<dtm> HE LIKES IT!
<Commn> dtm : haha how long did it take to find that picture?
<dtm> Commn: somebody gave it to me and i kept it in a firefox tab all week coz it's so awesome coz
I KNEW IT WOULD HAVE A GREAT PURPOSE
<dtm> Commn: since you asked for feedback, i'll say that you're extraordinarily diligent and conscientious, and
the minority of that content is directly relevant to mplayer, and the majority is relevant to a "how to ask
questions the smart way" type of document if not being totally redundant thereof
<dtm> you are a gentleman and a scholar, and true patriot
<sacarasc> dtm is cute when he is adoring someone
<Commn> dtm : yes, its a modified 'how to ask questions' docu
<Commn> its lame tho
<Commn> i might delete it
<Rathann> dtm is such a clear case of user-support-induced insanity that I wonder why I am still sane sometimes...
</pre>

<pre>
<pianoboy3333> how long does mplayer take to compile?
<dtm> how long til the Point of Know Return?
<pianoboy3333> ...
<dtm> i'm sorry, was that question not as dumb as yours? oh well i tried!
<dtm> <3
<iive> dtm: you are starting to sound like me.
<dtm> Hmmmm.
* dtm commits honorable ninja suicide
</pre>

<pre>
<Erb> Does anyone know how to launch the GUI MPlayer in Linux via PHP (in Firefox)? I can run MPlayer scripts
in the background fine. I only need to do this for local videos for an application I'm building.
* dtm throws his brain into a blender in an attempt to comprehend Erb's question but fails sadly
</pre>

<pre>
<dtm> tell me what i want to know, and nobody gets hurst.
<dtm> hurt.
<Rathann> o_O
<dtm> i'm feeling like the giant cactus wants to be plastered in ascii screenshots
<dtm> I MUST COMPLY
<dtm> HELP ME DO THIS, Rathann
</pre>

<pre>
<DazBrum> what is the channel for developers
<-- DazBrum has quit ()
<dtm> lols
<dtm> i think i'll spare them from that
</pre>

<pre>
<netstat> how come mplayer eating memory
<netstat> it uses up to 90% cpu
<dtm> must be a good movie
</pre>

<pre>
<cappicard> o/~ Ich versteh euch nicht! o/~
<dtm> i'm sorry cappicard i dont speak satanic
<cappicard> LOL
<cappicard> it's just German
<dtm> yeah but not when they're singing it.
<cappicard> heh :)
<iive> cappicard: isn't it the same
</pre>

<pre>
<gioele> How come that I get a 35 minutes MP3 from a 5 minutes FLV video with -dumpaudio?
<Compn> aliens beaming audio into your mp3
<spuck00> ^^
<gioele> Compn: time to call SETI?
<Compn> yep
<Compn> if the aliens are peaceful, say hello
<Compn> if they are aggressive, look out!
</pre>

<pre>
* richard___ wonders why so many people join this channel for no apparent purpose
<rsk> they share the love of mplayer ;-(
<sacarasc> i have a purpose
<richard___> I wasn't implying that there's anything wrong with it :)
</pre>

<pre>
<rms> please tell me how to use dd_rescue
<KotH> RTFM
<rms> and what special will it do, except regular copy?
<KotH> RTFM
<rms> RTFM?
<KotH> the manual says everything oyu need to know
<KotH> read the fucking manual
<rms> oh ok
</pre>

<pre>
<iive> -dumpvideo
<LinuxCart> umm, that's a good idea. i'll try that.
<LinuxCart> thank you iive
<KotH> LinuxCart: if in doubt, it's iive's fault ;)
</pre>

<pre>
<LinuxCart> how could this be explained?
<iive> it just another of dv misteries
<iive> it's KotH fault.
</pre>

<pre>
<LinuxMafia> how can i turn on language and sub
<KotH> RTFM
<LinuxMafia> KotH, using debian or freebsd?
<KotH> LinuxCart: doesnt matter, the FM is OS idenpedent
<LinuxCart> KotH: is RTFM some dialect to say it's iive fault :P
</pre>

<pre>
<ChaosR> MPlayer 1.0rc1-4.1.2-DFSG-free <- my version
<ChaosR> is it out of date
<mjunx> of course
<mjunx> if it wasn't built like within an hour ago at any given time, it's usually out of date
</pre>

<pre>
<Fatsobob> trying to get mplayer to play win32 on ubuntu makes me want to shoot myself
<Fatsobob> mostly because ubuntu is all "totem this" and "totem that"
</pre>

<pre>
<Quintin> Is there any reason to use opengl vo device?
<sacarasc> nope
<Quintin> what's it there for?
<sacarasc> because you might want to use it...
...
<reimar> sacarasc: is there any reason why I should think what you just said makes sense? ;-)
<sacarasc> reason and what people want are not always the same
</pre>

<pre>
<Commn> iive : dont call mplayer users dumb
<Commn> not to their faces anyhow
</pre>

<pre>
<Agiofws> has anyone tried cinerella ?
<Agiofws> i think it great
<Kunalagon> I tried , and I thin 80 % does not work
<MisT_> never get compiled here
<Kunalagon> it has more bugs than my shelter
</pre>

<pre>
<voltagex> ArneB: at one stage I was able to do the maths to crack CSS on paper :P
...
<ArneB> voltagex: Obviously your mind and paper are illegal.
<ArneB> Better hand them over to the MPAA.
<voltagex> I think you could sneeze and accidentally crack CSS
<voltagex> yep
<voltagex> no more pencils
</pre>

<pre>
<danny500> how do I convert a ogm file into an mpeg file using mencoder?
<danny500> anyone>
<danny500> hello?
<danny500> ?
<danny500> help
<BenrA> mencoder -of mpeg -oac lavc -ovc lavc -lavcopts vcodec=mpeg2video -o foo.mpg foo.ogm
<danny500> ?
<BenrA> If you want quality and/or DVD compatibility or anything, consult the docs. ;)
<danny500> ok that was confusing
<danny500> file equals = file:///home/danny500/Trigun/Trigun%20-%201%20-%20The%20%24%2460%20Billion%20Man
<danny500> now, rewrite that code so that It'll work
<danny500> well then?
<BenrA> What is your problem?
<housetier> I'd try replacing "foo.ogm" with /home/danny500/Trigun/Trigun%20-%201%20-%20The%20%24%2460%20Billion%20Man
(if that is the real file name), and see how far it goes
<danny500> fine then, don't help me, I'll go to a room where I'll actually get help. Fucking assholes
</pre>

<pre>
<crackedboy> hi, can I ask something about kmplayer?
<md`> no
<crackedboy> ok, sorry
<md`> you're forgiven
</pre>

<pre>
<CHodapp> I have a program that's basically just generating RGB data for a framebuffer.
<CHodapp> I'm having major issues figuring out how to get this data to an encoded video.
<CHodapp> ffmpeg seems to only want some particular kind of YUV
<CHodapp> can I make mencoder handle raw RGB or raw YUV or anything like that?
<Commn> its easier to get it working with mplayer, to see what options you need
<Commn> mplayer file -demuxer rawvideo -vc rawbgr16
<Commn> etc
<Commn> then you can do mencoder with those opts
<Commn> or maybe even mplayer -vo yuv4mpeg , which ffmpeg probably accepts
<Commn> maybe even use a named pipe... mkfifo stream.yuv && ffmpeg -i stream.yuv -options ...
<CHodapp> ugh, documentation is so sparse on stuff like this
<CHodapp> ugh, why is this such a pain in the ass, with everything
<CHodapp> hrm, maybe rawrgb24 is what I need
<Commn> what part is sparse?
<Commn> if you tell us, we can improve mplayer docs
<CHodapp> well, not so much in mplayer as everything else I've tried... I was mostly searching on
the web to get some clue of how I'd convert what kind of raw input to encoded output
<Commn> mplayer -vc help|grep raw
<Commn> will show what raw codecs mplayer has
<CHodapp> Yeah, I just now found that
<CHodapp> blah . . . Cannot find codec matching selected -vo and .video format 0x30323449.
<Commn> CHodapp : try -vc +rawrgb32 or whatnot
<Commn> just add + in front of it
<CHodapp> then it says the selected video_out device is incompatible with this codec
<CHodapp> tried sdl and x11
<Commn> if you can make a small sample of your file
<Commn> dd if=input of=output count=3 bs=1024k
<Commn> i can try to get it working in mplayer
<CHodapp> you might as well just take 640*480*3*100 bytes of data from /dev/urandom and try
that... it will be functionally equivalent
<CHodapp> I'm using this right now: mplayer -rawvideo w=640:h=480 -demuxer rawvideo -vc +rawrgb24 -vo sdl temp.rgb
<Commn> whats random got to do with it ?
<CHodapp> it's just a bunch of bytes, completely unorganized, and mplayer needs to know the resolution
<CHodapp> it doesn't care about the contents
<CHodapp> something else is wrong, otherwise I'd be getting something on the screen
<Commn> if you give me some file i can help
<Commn> otherwise its hard to debug from here ;p
<CHodapp> www.uc.edu/~hodappcm/temp2.rgb
<CHodapp> not the most coherent video, but you won't find that out unless you get something on the screen
<CHodapp> it's 320x240, 10 frames worth
<Commn> what program generates it ?
<CHodapp> just something I'm writing. it's all procedural.
<Commn> i'm trying to remember why it defaults to i420
<CHodapp> i420? like yuv?
<Commn> ya
<CHodapp> definitely shouldn't be yuv...
<Commn> i know, mplayer -rawvideo is defaulting to that
<CHodapp> hmm
<CHodapp> still no output?
<Commn> CHodapp : something like this didnt work ? ffmpeg -f rawvideo -pix_fmt rgb24
<CHodapp> couldn't find codec parameters...
<CHodapp> wait, I forgot the size
<Commn> haha more static
<CHodapp> what commandline did you use?
<Commn> ffplay -f rawvideo -pix_fmt rgb24 -s 320x240 temp2.rgb
<CHodapp> wonder if my endianness is wrong...
<Commn> is it black frames ?
<Commn> ffplay -f rawvideo -pix_fmt bgr32 -s 320x240 temp2.rgb
<Commn> CHodapp : http://64.233.167.104/search?q=cache:0o70XuNe5QkJ:www.kingcot.eclipse.co.uk/unichrome/tvoutTest.html+mplayer+rawvideo+rgb&hl=en&ct=clnk&cd=50&gl=us&client=opera
<Commn> CHodapp : there is an app on that page which generates rgb data
<CHodapp> yeah...
<CHodapp> by the way, I just sent you data from /dev/urandom
</pre>

<pre>
<Jan-> Just so you know, you do realise, the reason we're after using mplayer is because it's f@&^@ng brilliant.
<Jan-> It plays, as they say, *.
<Jan-> It'd play a bucket of cornflour if you painted the word "MOVIE" on it.
</pre>

<pre>
<nyersa> do I need to also specify the aspect ratio?
<Rathann> that's too vague a question
<Rathann> so my answer is: maybe
</pre>

<pre>
<judaz> i hear music, but not de voices
<judaz> the *
<Rathann> well, it's good that you don't hear voices
<Rathann> hearing voices is usually a sign of insanity
</pre>

<pre>
<sacarasc> i want mplayer 1.0 final so i can laugh and hell freezes over and people stop being idiots
</pre>

<pre>
<ma3x> what do you need mplayer for?
<ma3x> full of bugs
<ma3x> get windows media centre
<rsk> yea
<rsk> get a brain
</pre>

<pre>
<individ> using mplayer revision 26668 fixed my obscure problem, thanks for the tough love :]
</pre>

<pre>
<^^MAg^^> Arwen: I'm not blind, it's using ffh264
<Arwen> ^^MAg^^, and where do you read "x264" in that?
</pre>

<pre>
<ProN00b> Kovensky, i like it better without ass
</pre>

<pre>
<Kovensky> ProN00b: you're weird
<anon32> Kovensky, why? Because he likes his text without ZOMGPONIES?
<ProN00b> no, but there are no ponies anyways, just smaller text
</pre>

<pre>
<Compn> the topic is getting a bit large
<Zider> compress it with H.264
</pre>

=== #ffmpeg ===

<pre>
<grepper> you don't have -pix_fmt ?
<aum> '-pix_fmt list' worked - it just isn't advertised on the manpage
* aum pays due respect, and acknowledges that the *real* manpages are those files ending in .c, .h, .cxx etc
<grepper> it sure IS in my manpage
<grepper> maybe debian makes it from ffmpeg -h
</pre>

<pre>
<jaredthane> Now I'll just shoot myself in the head for being so stupid!
<andoma> do you want help with that as well? :-)
</pre>

<pre>
<benoit-> zinfandel: read the code
<benoit-> and come back when you know what you're talking about
<zinfandel> thats the 15 minutes i dont have now, but ok you win
</pre>

<pre>
<kshishkov|work> well, strictness of laws here is compensated by inability to enforce them often
</pre>

<pre>
<encompass> so what does FFMpeg actually stand for?
<Kuukunen> fast forward moving picture experts group
</pre>

<pre>
<peleg> oh, awful!!!
<peleg> these terrible sounds ripped my ears...
<iive> aac have been committed to ffmpeg?
</pre>

<pre>
<bigbear2> ok r 15190 is fine too
<zap0> is that 'stable' version now?
<Rathann> zap0: define 'stable' ;)
<zap0> somewhere you keep horses
<Rathann> oh, the horses have run already
<zap0> wild horses... damn you horses!
</pre>

<pre>
<Hfuy> TroyMcClure?
<TroyMcClure> yep
<Hfuy> the TroyMcClure we remember from such video-conversion instructional films as "MPEG-4 - Suitable for Porn?"
</pre>

<pre>
<Hfuy> In order to make FCP* display this stuff without insisting on a render, all the stars will have to be in alignment, if you see what I mean.

* Final Cut Pro
</pre>

<pre>
<Dark_Shikari> Most NLEs are utterly trashy pieces of software
<Dark_Shikari> with video support that makes most late-90s apps look good
<Hfuy> Couldn't agree more.
<Dark_Shikari> despite being supposedly "professional" video editors they don't actually support any "professional" formats
<Hfuy> However, they are utterly trashy pieces of software I am bound to support.
</pre>

<pre>
<Hfuy> Uh-oh. Looks like it needs to me MXF-wrapped.
<Dark_Shikari> does FCP take DirectShow input?
<Dark_Shikari> I know Premiere does.
<Hfuy> Final Cut is available only on the Mac.
<Hfuy> This makes my life... interesting.
<Hfuy> Premiere also knows how to import EDLs with timecode and so forth, which FCP doesn't; absolutely the only way to get anything into FCP is using Quicktime embeds.
[...]
<Dark_Shikari> you're intentionally torturing yourself ;)
</pre>

<pre>
<Hfuy> You are aware I assume of what an egregious train wreck of a format MXF is.
<Dark_Shikari> so there's no mxf muxer I'd assume
<Dark_Shikari> I don't pay attention to awful container formats :>
<Dark_Shikari> that's the great part of working on a pure encoder app, you can let the ffmpeg devs torture themselves over awfully designed container formats instead ;)
<Hfuy> MXF is extremely awful. One cannot help but raise an eyebrow when a container format touts itself as solving all interchange problems, overnight and for ever.
<Dark_Shikari> lol
<Hfuy> What it actually does is take the interchange problem, wrap it up in a pretty box with a ribbon on it marked "MXF", and pretend that helps.
<Dark_Shikari> I think there's some inverse relationship between marketing claims and actual substance
<Hfuy> If it's any consolation, I'm having enormous grief trying to create timecoded Quicktimes on a Windows PC.
</pre>

<pre>
<Hfuy> ...yes, AVCI is MXF-wrapped. Curses.
<Hfuy> Oh, good grief, it's split-file A/V.
<Dark_Shikari> oh god
<Dark_Shikari> its not even interleaved?!
<Hfuy> With external XML metadata.
<Hfuy> I believe MXF can be. But in the case of AVC-Intra, it's not.
<Dark_Shikari> :>
* Hfuy allows his head to fall forward onto the desk
<Hfuy> What in God's name is --wrong-- with these people?!
<Dark_Shikari> lol
<Hfuy> Allow me to quote from the AVC-Intra whitepaper.
<Dark_Shikari> ugh, whitepapers
<Hfuy> Basic concept of AVC-Intra
<Hfuy> Guarantee interoperability Adoption of International video coding standard and MXF fle format
<Hfuy> Words fail me.
</pre>

<pre>
<Hfuy> So, how much money do I have to give you to have you implement MXF wrapping to SMPTE 381M?
* Hfuy ducks
<Dark_Shikari> I'm not going to touch it with a 10 foot pole :>
<Hfuy> So let me get this straight, for a moment. We can have ffmpeg create the highly advanced compressed video data, but we can't make FCP read it, because it isn't wearing a nice enough suit?
<Dark_Shikari> lol
<Hfuy> Don't mock the afflicted.
<Hfuy> Doesn't this imply that FCP's importer is rather lacking in the generality department?
<Dark_Shikari> what, you're surprised?
</pre>

=== #ffmpeg-devel ===

<pre>
<superdump> well, i've been hailed as a guru and i'm owed a pint (see #ffmpeg)
<superdump> hehe
<andoma> i want a pint too!
<superdump> it's loud and annoying
<kshishkov|work> so what, I've got one marriage proposal (from female) there once
<superdump> o rly?
<andoma> that ranks higher indeed ..
<andoma> kshishkov > superdump
</pre>

<pre>
<caldo_de_cana> ok, I need a little CS help... my callback function for vfwcap
locks a mutex to add packets to a list. lavf's read_packet function also locks
the same mutex to read packets from the list. If there are no packets on the
list and read_packet has to wait, I could make it wait for a semaphore that is
set from inside the callback, right?
<iive> lavf (ffmpeg in general) using mutex is news for me.
<caldo_de_cana> iive: windows stuff... I had to make up for vfw's misdesign
<caldo_de_cana> actually it's lavd... most files there have huge hacks
* iive runs and hides
* mru makes up for windows misdesign by not using it
</pre>

<pre>
* KotH threatens to not bring any chocolate to next LT
<mru> noooo
<mru> KotH: what are your demands?
<KotH> uhm... that you do something... or dont do it... dont know
<mru> well, I'm doing something, and I'm also not doing some things
</pre>

<pre>
<KotH> chocolate is serious business!
</pre>

<pre>
< patrakov> yes, I have already solved one organizational issue (invalid XML from clueless partners)
<@mru> all xml is invalid
<@mru> or should be
</pre>

<pre>
<mru> when it locks up, it only responds to external reset
...
<mru> it's almost impossible to intentionally trigger the bug
<mru> so far, the most reliable way has been to run ffmpeg for a few minutes
<mru> FFmpeg, killer of compilers and CPUs alike
</pre>

<pre>
<Dark_Shikari> (Reminds me, a bit ago when I sent in a patch to implement a feature for H.264 decoding, Michael messaged me giving me a really clever way to do it, saying we should commit the better way in a few months after waiting for all competitors to do it the inefficient way.)
<Rathann> did he, really?
<Dark_Shikari> yes
<Dark_Shikari> He's just that awesome
</pre>

<pre>
<mru> the only "valid" reason I can think of for using theora is because it works in ogg
<mru> and the only "valid" reason I can think of for using ogg is that theora works there
</pre>

==Mailing lists==

===[http://lists.mplayerhq.hu/mailman/listinfo/mencoder-users mencoder-users]===

<pre>
> But trust me: Both Core Duo and Core 2 Duo support 64bit extensions,
> almost identically.

Don't trust me! I'm wrong! I'm ashamed! There do exist Core Duos
without AMD64/EM64T/Intel 64 extensions.
-- Moritz Barsnick, correcting himself
</pre>

===[http://lists.mplayerhq.hu/mailman/listinfo/mplayer-cvslog mplayer-cvslog]===

<pre>
> btw, anyone has a copy of the ISO-english spec? ;)

Ok. :)

1. There isn't a spec, since the language hasn't been standardized. All
we have are numerous competing drafts written by independent,
non-authoritative organizations.

2. A large amount of existing English code, such as Shakespeare, is
unparseable by modern English speakers.

3. If an element of the language has been frequently misused over a long
enough period of time, such misuse often becomes acceptable.

4. An English speaker can be considered reasonably feature-complete even
if such speaker only recognizes a small subset of the language.

5. Certain keywords tend to cause internal compiler errors. Such
keywords are known as "profanity", and existing English speakers weakly
attempt to prevent recently-written speakers from being aware of them.

6. English is a highly context dependent. Many keywords, when used in
their own particular context, take on an entirely illogical meaning.
These "idioms" cause compilation errors, especially when an old speaker
is attempting to communicate with a new one.

7. ....

I could go on, but that's enough fun for now. :)
-- Michael Niedermayer and Corey Hickey in mplayer-cvslog at mplayerhq.hu
</pre>

<pre>
On Sat, Dec 01, 2007 at 02:35:25PM +0100, reimar wrote:
> Author: reimar
> Date: Sat Dec 1 14:35:25 2007
> New Revision: 25225
>
> Log:
> Fox typos

well ...

[...]
--
Michael
</pre>

<pre>
Author: michael
Date: Thu Sep 4 21:49:13 2008
New Revision: 27519

Log:
Fix 4 of the unscaled rgb15/16 converters, each of these contained
2-3 bugs each of which made it fail completely, this code clearly
has never been tested and been written by somone who knows the
difference between a potato and a computer is that the first is round.
</pre>

===[http://lists.mplayerhq.hu/mailman/listinfo/mplayer-dev-eng mplayer-dev-eng]===

<pre>
Without a frontend, mplayer is useless.
-- Jean-Philippe Guillemin in mplayer-dev-eng at mplayerhq.hu
</pre>

<pre>
[about alsa resampler]
Now why on earth would anyone want to use this crap?? It's only
configurable between two extremes of sucking: very bad quality, or
very bad performance.
-- Rich Felker in mplayer-dev-eng at mplayerhq.hu
</pre>

<pre>
Reinventing the wheel certainly is annoying, but as long as all other
wheels are square...

Reimar Döffinger
</pre>

<pre>
On Thu, Aug 24, 2006 at 01:10:18PM -0400, Dave Dodge wrote:
> IA64 compilation is an ongoing research project.

Which is what leaves me always wondering where on earth (or actually far
away from earth) Intel engineers left their brains when designing
IA64...
Technology for the next century. As in we will get it to work properly
somewhen in the next century...

Reimar Döffinger
</pre>

===[http://lists.mplayerhq.hu/mailman/listinfo/mplayer-users mplayer-users]===

<pre>
> > yes, video decoding is not perfect either so even if u decode the bitstream u
> > loose quality (idct inaccuracies and such) so u should really use a hexeditor
> > instead of mplayer to view ur movies
>
> Perhaps we could rewrite xmatrix so it takes its input from AVI
> files...

"Do you always look at it encoded?"

"Well ya have to. The video codecs work FOR the construct program. But
there's way too much information to decode this DIVX. You get used to
it -- I don't even see the code. All I see is blonde, brunette,
redhead..."
-- Michael Niedermayer, Moritz Bunkus and D Richard Felker III in mplayer-users at mplayerhq.hu
</pre>

<pre>
>>> Is there any possibility to convert a Ream Media video stream to
>>> ogg/theora video?
>>
>> no, ogg is banned for good from the list of possible outputs for
>> manifest insanity
>
> Thank you for your answer, but can you be more specific?

ogg is by far the most insane mux format ever conceived,
thus no conscious coder wants to permit to give birth to an abomination
like that
-- Marek Mahut and Nico Sabbi in mplayer users at mplayerhq.hu
</pre>

<pre>
> > > 1. ok, true, I wanted to say mad TAG right ? How can I get this
> > > to MP3 tag ?
> >
> > There is no such thing as a MAD tag. MAD only plays MP1/MP2/MP3.
> > Your file has to have one of those as the audio track for MAD to be
> > able to play it at all. You also didn't read the rest of my post.
>
> MAD audio codec then ?

...

I'd love to help, but I have to go bang my head against that wall over
there...
-- wim delvaux and RC in mplayer-users at mplayerhq.hu
</pre>

<pre>
Tobias Damisch wrote:
> Guillaume Poirier wrote:
> > MPlayer still lacks "fairies" support to invent the pixels in between,
> > needed to get a truly HD picture.
>
> Just get latest SVN and recompile with:
>
> --enable-fairies
>
> Then try adding -vf fscale=1600:1200 (or any other resolution you
> might desire) to your command line.

Gentoo's latest mplayer ebuild is apparently an SVN snapshot from
08/10/2006 and doesn't seem to include a fairies USE flag for
compilation. Was fairies support added after that date, or is the
ebuild missing a USE flag?

Grant
</pre>

===[http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-cvslog ffmpeg-cvslog]===

<pre>
>> I'm sure Michael knows how to capitalize and punctuate at
>> least a little bit.
> thats defamation, ive never capitalized and punktuated correctly
> besides that i dont like pure capitalism ;)
I NEVER ASKED YOU TO WRITE LIKE THIS.
-- Måns Rullgård and Michael Niedermayer in ffmpeg-cvslog at mplayerhq.hu
</pre>

<pre>
Michael Niedermayer CVS <michael@mplayerhq.hu>

Modified Files:
ffmpeg-doc.texi
Log Message:
split string to avoid buffer overflow in native english speaking persons (fix suggested by The Wanderer)
</pre>

<pre>
On Mon, Dec 26, 2005 at 09:57:36PM +0100, Alexander Strasser wrote:
> Oh, I just saw it was in the original mail. I must have
> accidently deleted it while writing the answer. Sorry for
> the trouble.

no problem at all, better to ask then to miss some typos by the CIA/KGB guys
who edit all my outgoing and incoming mails

Michael
</pre>

<pre>
>>>Log:
>>>use pr -n -t instead of non-standard cat -n
>>>
>>Is this purely to be standard compliant or did you manage to find a
>>system that doesn't accept cat -n?
>
>Rich has one, apparently.

That's funny...
I admire FFmpeg's standard compliance. It gets to the point where you
create systems to justify such changes.
-- Måns Rullgård and Ramiro Polla
</pre>

<pre>
Besides, people with non-compliant systems need to be taught a lesson.
-- Måns Rullgård
</pre>

===[http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel ffmpeg-devel]===

<pre>
On Mon, Jan 02, 2006 at 05:14:20AM +0100, Michael Niedermayer wrote:
> Hi
>
> On Fri, Dec 16, 2005 at 03:45:37PM -1000, Steve Lhomme wrote:
> > This code moves the AR detection in the codec part so that it works when
> > the DV stream is in AVI (or else) too. Plus the interlacing detection
> > now works.
>
> roman, please choose
> [ ] patch ok
> [ ] patch not ok
> [ ] dv maintainer lazy
> [ ] dv maintainer busy
> [ ] dv maintainer dead

Michael you've forgotten a very important option for somebody who decided
to celebrate New Year in Russia:

[X] dv maintainer drunk
</pre>

<pre>
> All right, new screening process for prospective FFmpeg contributors:
> "Are you now, or have you ever been, a Microsoft Visual C++ user?"
> There's going to be scandal when the oversight committee investigates my
> employment history.
If you used msvc on your day job it doesn't count, as long as you really hated it.
-- Mike Melanson and Måns Rullgård in ffmpeg-devel at mplayerhq.hu
</pre>

<pre>
>>>I never understood the point of those supposedly "cool" aliases some
>>>people use.
>>
>> What about the supposedly "cool" circle you put over the 'a's in
>> your name? :)
>
>
> It's Swedish and turns the 'a' into something that sounds like an 'o' as
> in 'hot'...

Ah, so that's the difference. It's not "cool", it's 'hot'.
-- Måns Rullgård, Mike Melanson, and Diego Biurrun in ffmpeg-devel at mplayerhq.hu
</pre>

<pre>
> patching file configure
> Hunk #1 FAILED at 914.
> 1 out of 1 hunk FAILED -- saving rejects to file configure.rej
Ah, yes, the swift evolution of ffmpeg made the patch obsolete in 24h.
-- Måns Rullgård and Víctor Paesa in ffmpeg-devel at mplayerhq.hu
</pre>

<pre>
[about the lack of "chained ogg" support]
I'm aware of this problem, and I've been trying to think of a
solution. The more I think about it, the more it appears as an
abomination. Just like everything Ogg related. No surprises there.
-- Måns Rullgård in ffmpeg-devel at mplayerhq.hu
</pre>

<pre>
not everything from OO is necessarily bad, like not everything from M$
is necessarily bad, if later where the case M$ would gone bankrupt long
ago ...
but thats geting deeply off topic, lets rather concentrate on flames and
insults ...
-- Michael Niedermayer in ffmpeg-devel at mplayerhq.hu
</pre>

<pre>
[Marco Gerards submits a THP demuxer]
Coooool. I have hundreds of THP files. I will find some that have sound
and get them posted soon. In the meantime, Niedermayer will be along
shortly to tear apart your patch. Good luck! :)
-- Mike Melanson in ffmpeg-devel at mplayerhq.hu
</pre>

<pre>
[about SwScaler rewrite]
> > And then we can call an architecture dependent init function that can
> > overide the C behavior much like is done for the dsputils.
> I was thinking about that too
thinking is good patch is better ...
-- Marc Hoffman, Luca Barbato and Michael Niedermayer in ffmpeg-devel at mplayerhq.hu
</pre>

<pre>
On Sun, Jan 15, 2006 at 06:27:55PM +0100, Reimar Döffinger wrote:
>
> Oh, and the image of my RE drawing is up as well :-) :
> http://www.stud.uni-karlsruhe.de/~uvhe/LZODraw_bw.png

Thank goodness your coding skills are better than your handwriting ;)

Diego
</pre>

<pre>
On Thu, Sep 22, 2005 at 10:51:05AM +0200, oandrieu@gmail.com wrote:
> Michael Niedermayer [Wednesday 21 September 2005] :
> > cosmetics
>
> Yes. And ?

sorry, i should have been more verbose, maybe i should be restarted with -v
can someone of the admin(s) do that?

Michael
</pre>

<pre>
as far as i can see this AVI file has _many_ video frames in each chunk, sick
how can a person be capable of using a text editor (and writing software) and
at the same time be such a complete idiot writing a program generating so
broken avi files ...

Michael
</pre>

<pre>
michaels law: "if gcc can mess up, it does mess up" ;)
</pre>

<pre>
> >> + "psllw $1, %%mm1 \n\t"
> >> + "psllw $1, %%mm2 \n\t"
> >
> > paddw
>
> Is that always faster?

no, you can design a cpu where its not

Michael
</pre>

<pre>
if you think that this patch will be accepted due to you whining how much
time you spend on it already then you live in some strange fantasy world
-- Michael Niedermayer in ffmpeg-devel at mplayerhq.hu
</pre>

<pre>
Rich, I always knew you were a little out of the ordinary, but
pirating gay porn wasn't quite what I was expecting even from you.
-- Måns Rullgård in ffmpeg-devel at mplayerhq.hu
</pre>

<pre>
[after a discussion of a patch with a new audio decoder evolved into
runtime generation of tables vs. hardcoding them in the object file debate]

what is the name of this bikeshed?
-- compn
</pre>

<pre>
On Thu, Oct 18, 2007 at 11:04:23AM +0200, Jean-Michel Pouré wrote:
> Some days ago, Christian Marillat reported that it was impossible to
> compile ffmpeg/libavcodec packages under Debian. Any idea where the
> problem comes from? Was it fixed lately?

Sure. My crystal ball tells me that fiendish aliens have been using
force fields to obstruct the flow of cosmic energies in Christian's
machine. The fact that the aliens have decided to sabotage FFmpeg first
should give us all pause. It is a rare compliment to receive but it
carries along a great responsibility.

Now everybody remember that the survival of the human race rests on our
shoulders. If we are to remain victorious in this epic conflict we must
not succumb to darkness. The pureness of our hearts is our most potent
defense. We must preserve it at any cost.

Diego
</pre>

<pre>
On Tue, Oct 30, 2007 at 12:15:28AM -0400, Ronald S. Bultje wrote:
[...]
> I'm not "they" anymore, I left Fluendo +/- 2 1/2 years ago and GStreamer +/-
> 2 years ago.

i see, ill get the kgb chief liquidated for providing me with outdated
information

Michael
</pre>

<pre>
On Fri, Dec 14, 2007 at 08:01:51PM +0100, Diego Biurrun wrote:
[...]
> > + * @file rectanlge.h
>
> rectANgle.h

diego: /dev/brain: Permission denied ;)

Michael
</pre>

<pre>
The only officially correct spelling of snow is in the form of a frozen
snowflake placed on 5000 year old papyrus and illuminated by the light of
a population III star.

Now please diego fix it to the official spelling!

Michael
</pre>

<pre>
O, mercyfull Diego, hast thou not given the dear needed access?
Wherefore did thou create ye, if not to commit?

Michael
</pre>

<pre>
FFmpeg preys on weak, unmaintained or closed-source codecs. If your
library does not meet those requirements, ffmpeg won't consume it (and
will use a wrapper if it is good one).

Kostya
</pre>

<pre>
>
> Just curios, is it possible to add hardware DVD, h.264 and VC-1 decoding to ffmpeg?

Yes, through ./configure --dont-hijack-threads --see-ffmpeg-users

Benjamin Zores
</pre>

<pre>
Thats like giving a painting from Leonardo da Vinci to a wild boar so it can
correct the fine details.

Michael
</pre>

<pre>
But the only correct usage of autotools is as argument to rm

Michael
</pre>

<pre>
Diego Biurrun wrote:
> I came across this excellent paper from 15 years ago:
>
> #ifdef Considered Harmful, or Portability Experience With C News
>
> It's a nice short read and emphasizes the experiences we have had around
> here. It also comes to very similar conclusions, which is quite
> gratifying.

In the other news water is considered harmful yet useful...

lu
</pre>

<pre>
> > > > Considering 'lag' versus 'delay', I think I have consistently used
> > > > 'lag' in my AMR code I think, mainly because it's shorter. :)
> > >
> > > Repent ye bloody sinner! Thy code showest the innermost part of thy
> > > heart, lagging as it is behind the times! Now delay ye no longer with
> > > updating it as thy Lord commands ye!
> >
> > I didnt know robert was worshiping the spirit who denies everything always.
>
> He has taken to worshipping all manner of devilishly spirits, as
> islander folks are known to do ...
>
> > And reconsidering the whole, if they are equivalent, the shorter has
> > some undenyable advantage.
> > Dont ye agree?
>
> Nay, ye mind is clouded by the charms of the islander's charms. Pray
> that the daemon's have mercy upon ye and lift those spells from thou...

If you ever write a fantasy novel id want a copy ...

Robert Swain, Diego and Michael
</pre>

<pre>
> My spare time is taken up 20% MythTV, 10% SCST, 85% drinking heavily.

And the remainder you spend on maths studies, right?

Some man and Måns
</pre>

<pre>
[some weird problem on MacOSX 10.5]
> The regular not-postfixed symbols are there, however. It's just that the
> compiler ignores that it's compiling for an older version whenever it
> encounters the _XOPEN_SOURCE flag.

Our code conforms to widely accepted standards. Your compiler decides
to replace a few symbols with non-standard names, which the linker
then cannot find. Around here, that's called Your Problem.

> To fix compiling on OSX for older versions, all _XOPEN_SOURCE
> definitions should check for __APPLE__ first.
>
> #if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
> # define _XOPEN_SOURCE 500
> #endif

In my part of the world, when there's a hole in the road, they don't
require people to mount wings on their cars; they fix the hole. You
should do the same. Or stay home.
-- Adrian Stutz and Måns
</pre>

<pre>
>> In file included from /usr/include/math.h:26,
>> from ./libavutil/mathematics.h:25,
>> from ./libavutil/avutil.h:57,
>> from liba52/parse.c:40:
>> /usr/include/architecture/ppc/math.h:179: error: parse error before
>> '__attribute__'
>
> Well, wtf is in math.h that it stumbles over?

This is getting better and better. First macosx can't link with its
own libs, and now it can't even compile its own headers. If this
keeps up, it won't be long before it stops booting at all, and we'll
finally see an end to these problems.
-- Guillaume, Reimar and Måns
</pre>

<pre>
> Oh, one more thing: In my world it is common to top-reply (and I am

Then we don't like your world. Please go back there, and don't come
here again.

> doing this for almost 29 years). But now I know that the FFmpeg

I see you're attempting a proof by doing-it-for-a-long-time approach.
That doesn't work in this world.
-- Frans de Boer and Måns
</pre>

<pre>
> balatoni denes tried to get a half optimized idct in and i nicely told
> him that it has to include all tricks and optimizations we could think of.
> We ended up with something that was clearly quite a bit faster than
> what he submitted first, that is between all the complaints about how
> little time he had and how evil we were for not just acceptiing it as
> is.

The Legend of the Warrior - now I am officially part of the ffmpeg
mythology :)
-- Michael Niedermayer and Balatoni Denes
</pre>

<pre>
> Do you intend to actually implement a .ass demuxer?

As you ask so nicely, Ill see what i can do. Iam starting to think that
it might take less time to just implement everything related to ASS than
continue this discussion.
-- Uoti Urpala and Michael Niedermayer
</pre>

<pre>
[about withdrawing Snow development prize/donation]
>>> I'll be sorry to do this but it seems snow will die before beeing born.
>>
>> Well it seems that as 2008 comes to a close, Loren's prediction has
>> finally been proven wrong ;)
>>
>> (from ~2005)
>> <OpenSourced> where do you think x264 will be in 3 years
>> <pengvado> replaced by snow :)
>>
> Darn, I thought you x264 devels were expert at various types of
> prediction...

That was only the first pass.
-- Lars Täuber, Jason Garrett-Glaser, Andreas Öman and Måns Rullgård

</pre>

===[http://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-soc ffmpeg-soc]===

<pre>
Alexander Strange wrote:
>
> On Apr 23, 2008, at 2:24 PM, vitor wrote:
>
>> Author: vitor
>> Date: Wed Apr 23 20:24:46 2008
>> New Revision: 2152
>>
>> Log:
>> Replace if(acroread appli_Goethe.pdf &){B}else{C} by if(a){C}else{B}
>
> Too much tab completion?

Is there a price for the most nonsense commit log? ;-)

-Vitor
</pre>

===[http://lists.mplayerhq.hu/mailman/listinfo/nut-devel NUT-devel]===

<pre>
We should have some nut samples.
Someone, (not me, I am lazy), should mux some free video and
audio into NUT (or just grab a camera and film something funny
like what happens with an egg in the microwave or something
else where A-V sync can be seen).

Michael
</pre>

<pre>
A "spec" as readable as a sendmail configuration file doesn't make
matters better...

Måns Rullgård
</pre>

===other===

<pre>
i've remembered i have root access at new mphq, but probably
it was just a dream :)))
-- A'rpi
</pre>

<pre>
FFmpeg works like a human being: something nice comes in, crap comes out.
-- superdump on an S-Bahn train in Berlin
(written from memory, please fix)
</pre>

<pre>
Michael Niedermayer <michaelni@gmx.at> added the comment:

this is for bugreports not guess reports
</pre>

<pre>
Sun Nov 11 10:32:18 CET 2007
Previous message: [Ffmpeg-user] Anyone?
>Anyone?

someone?

>I still can't make it work.

have you tried cialis?

of course maybe you're referring to an audiovisual problem,
and maybe it even pertains to ffmpeg...
really hard to tell!

tripp
</pre>

<pre>
Breaking DRM is a little like attempting to break through a door even
though the window is wide open and the only thing in the house is a bunch
of things you dont want and which you would get tomorrow for free anyway
-- Michael Niedermayer
</pre>

<pre>
Hello,

I have downloaded the latest version of vhook modules from
"svn://svn.mplayerhq.hu/ffmpeg/trunk"
but they are a bunch of .c and .h files.
Please tell me how to generate a .dll file from them.
I am using Windows XP.
Thank you.

-- An ordinary Windows user on ffmpeg-user (long lines broken manually
and Yahoo signature removed to keep the wiki clean)
</pre>

FFmpeg Summer Of Code 2008

2008-03-18T01:14:27Z

Dark Shikari: /* x264 Improvements */

Google is sponsoring their fourth annual [http://code.google.com/soc/2008/ Summer of Code] for the summer of 2008. This entails paying students for working on open source projects. FFmpeg has been a participant in the 2006 and 2007 seasons. Visit the main [[FFmpeg Summer Of Code]] page for information on past seasons.

FFmpeg has been selected to participate in GSoC 2008. This page discusses possible project ideas and status for the Google Summer of Code 2008 season as it pertains to FFmpeg.

The administrator for the FFmpeg Summer of Code is Mike Melanson, a.k.a. [[User:Multimedia Mike|Multimedia Mike]]. His email address is mike -=at=- multimedia.cx.

'''If you are a student''' who wishes to be '''involved with a FFmpeg GSoC''' project, one of the first and best steps you can take is to subscribe to the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list], sooner rather than later, and indicate your interest. In the past, we have weighted our selection decisions by how involved a prospective student is. And remember to read the part of this page dealing with qualification tasks since you '''absolutely must''' complete a qualification task to be eligible for a FFmpeg SoC project. No qualification task, no project. No exceptions.

== Current Status ==
* '''Next Big Date:''' March 24, 2008: Students may submit applications through Google
* March 17, 2008: Google is scheduled to announce selected projects; ''FFmpeg is selected''
* March 3, 2008: Submitted FFmpeg project application
* February 20, 2008: Created page

== Schedule ==
Official timeline: http://code.google.com/soc/2008/faqs.html#0.1_timeline
* March 3-12, 2008: Open source organizations may apply to the Google Summer of Code program.
* March 17, 2008: Google is scheduled to announce accepted organizations at: http://code.google.com/soc/
* March 24-31, 2008: Students may submit applications for various Google Summer of Code projects.

== Application Process ==
The student application process for 2008 will be as rigorous, if not more so, than in 2007.

[http://code.google.com/opensource/gsoc/2008/faqs.html#0.1_timeline From the formal timeline]:
* March 24, 2008: Student application period opens.
* March 31, 2008: Student application deadline.
* April 11, 2008: Final decisions are made.

All students who wish to be eligible for a GSoC FFmpeg project '''must''' successfully complete a qualification task. A student may submit an application before completing their task and they will have until April 11, 2008 to finish a qualification task. It is ill-advised to wait until the last minute, though. You must ''complete'' the task, which involves getting code approved for submission to source control, which takes many iterations over many days for most people. Further, we like people who show initiative earlier than later.

== 1st Tier Project Proposals ==
1st tier project proposals are project ideas that are reasonably well defined '''AND''' have a mentor volunteered.

==== G.729 Encoder ====
* Specification: http://www.itu.int/rec/T-REC-G.729/e
''Mentor: Benjamin Larsson''

==== G.723.1 Decoder ====
* Specification: http://www.itu.int/rec/T-REC-G.723.1/en
''Mentor: Benjamin Larsson''

==== G.723.1 Encoder ====
* Specification: http://www.itu.int/rec/T-REC-G.723.1/en
''Mentor: Benjamin Larsson''

=== DTS Encoder ===
* Specification: http://wiki.multimedia.cx/index.php?title=Mirror
* Sample files: http://samples.mplayerhq.hu/A-codecs/DTS/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* There will be an existing encoder to extend, it will only produce 2 channel 44.1kHz streams.
* Primary goal: Encoder that can produce multi sample rate and multi channel files. Simple rate control. Wav and raw muxing support. Wav dts auto detection when decoding.
* Secondary goal: Techniques from specification implemented, optimal codebook usage, vector quantization, simple psycho acustics.
* Third goal: Advanced psycho acoustics.
''Mentor: Benjamin Larsson''

=== Nellymoser Encoder ===
* Specification: http://svn.mplayerhq.hu/ffmpeg/trunk/libavcodec/nellymoserdec.c?revision=11708&view=markup
* Sample files: http://samples.mplayerhq.hu/A-codecs/Nelly_Moser/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* Primary goal: Dumb bitstream compatible encoder
* Secondary goal: Simple psycoacousics implemented
''Mentor: Benjamin Larsson''

=== AAC-LC Encoder ===
* Sample files: http://samples.mplayerhq.hu/A-codecs/AAC/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* Primary goal: Dumb bitstream compatible encoder with flexible framework for a serious psychoacoustic implementation
''Mentor: Benjamin Larsson''
''Co-Mentor: Anderas Öman''

=== VP3/Theora Encoder ===
* Clearly defined task
* Primary goal: Encode video sequences such that they can be decoded by a VP3 decoder first, and then a standard Theora decoder.
''Mentor: Mike Melanson''

=== MXF muxer ===
* Specifications: SMPTE 377M
* Clearly defined task
''Mentor: Baptiste Coudurier''

=== MVC decoder ===
* Create an independent FFmpeg decoder for the [[Nokia MVC]] codec
* Very clearly defined task
* ''Mentor: Michael Niedermayer''

=== Apple Lossless Encoder ===
* Samples: http://samples.mplayerhq.hu/A-codecs/lossless/ALAC/
* Decoder: http://svn.mplayerhq.hu/ffmpeg/trunk/libavcodec/alac.c?&view=markup
* Encoder that works on Linux with Wine: http://www.dbpoweramp.com/dmc.htm
* Primary goal: Encode files which will decode losslessly using the FFmpeg ALAC decoder.
* Secondary goal: Make sure encoded files will decode losslessly with iTunes and play on an iPod.
* Reuse as much code as possible from other FFmpeg encoders, namely FLAC since it is a similar codec.
* Specifically, reuse the LPC code from FLAC and make it more generic so it can be shared with various speech codecs as well.
* As time allows, experiment with different parts of the codec to push the boundaries of FFmpeg's decoder and of the format itself.
Also see [[ALAC]] and issue [https://roundup.mplayerhq.hu/roundup/ffmpeg/issue82 #82].

''Mentor: Justin Ruggles''

=== Snow Job ===
This task involves finishing work on the [[Snow]] video codec to bring it to 1.0 quality.
* Document the whole Snow algorithm
* Fix all Snow related bugs on roundup
* faster halfpel interpolation (issue183)
* Try a different transform like an lapped biorthogonal transform instead of the wavelet (this could be better or worse only trying can tell ...)
* anything in [http://svn.mplayerhq.hu/ffmpeg/trunk/doc/TODO?view=co doc/TODO] about Snow and [http://svn.mplayerhq.hu/ffmpeg/trunk/doc/snow.txt?view=co snow.txt/TODO]
* anything else which might improve Snow quality per bitrate
''(The idea here is that the goal would be, do as much as the time allows, though we should decide on some minimum as all above is clearly not doable within the time)

''Mentor: Michael Niedermayer''

=== x264 Improvements ===
This task has been moved to the VideoLan project, and can be found [http://wiki.videolan.org/SoC_x264 here].

== 2nd Tier Project Proposals ==
All that separates these proposals from their 1st tier brethren is a mentor. If you are particularly passionate about one of these tasks, perhaps you should attach your name to it. ''(Email me if you want to discuss it or need access to the Wiki. --[[User:Multimedia Mike|Multimedia Mike]] 21:58, 1 March 2008 (EST))''

==== GUI for FFmpeg ====
Build a gui for the libs of FFmpeg. The main objective in this task is to extent the codecs and formats to support querying of features and good defaults. The actual GUI should just be a simple skeleton with support for encoding of multiple files. Most of the work will be done in the libs.

==== Port FFmpeg to Visual Studio ====
Create a full working port including inline assembly.

==== Optimize FFT routines ====
Port djbfft and rework the fft framework in FFmpeg. This task can include a fixedpoint port and SIMD optimizations.

==== GSM Decoder ====
* Specification + sample implementation: http://kbs.cs.tu-berlin.de/~jutta/toast.html
* Samples: http://samples.mplayerhq.hu/A-codecs/GSM/
Also see [[GSM]].

==== AMR-WB Decoder ====
* Specification: http://www.3gpp.org/ftp/Specs/html-info/26-series.htm
* Samples: http://samples.mplayerhq.hu/A-codecs/amr/
Also see [[AMR]].

==== AMR-NB Encoder ====
* Specification: http://www.3gpp.org/ftp/Specs/html-info/26-series.htm
* Samples: http://samples.mplayerhq.hu/A-codecs/amr/
Also see [[AMR]].

==== Speex Decoder ====
* Specification: http://speex.org/docs/
* Samples: http://samples.mplayerhq.hu/A-codecs/speex/
Also see [[Speex]].

=== WMV3 Encoder ===
* Clearly defined task
* Primary goal: Encode video sequences such that they can be decoded by a Windows Media player.

This could either be done by improving [[Interesting Patches#WMV3 encoder by Denis Fortin|this patch]] or by writing the encoder from scratch.

=== Better handling of audio in libavcodec ===
* Info: http://wiki.multimedia.cx/index.php?title=Ffmpeg_audio_api
* Loosely defined task

=== LGPL reimplementation of GPL sws_scale parts ===
* Loosely defined task
* Primary goal: LGPL licensed sws_scale
* Secondary goal: removal of lavc scaler

=== Freeform Proposal ===
If you think you have a good idea for a FFmpeg Summer of Code project, propose it on the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list]. We will discuss it from there.

== Qualification Tasks ==
Many students apply for the Google Summer of Code and wish to work on a sexy multimedia project such as FFmpeg. All students will claim to be hard workers but we need a method of determining which students have a higher probability for success. Thus, we developed the qualification system during the 2007 season and will be enforcing the same system this year. A student must successfully complete a qualification task in order to be considered for an FFmpeg SoC project. In doing so, a student demonstrates that they:

* are willing to commit some time during the Summer of Code application review period in order to prove themselves
* can code C satisfactorily and with the same general style expected of the FFmpeg codebase
* can wrap their head around the code base
* can interact with the FFmpeg development mailing list
* can accept feedback and revise the code until it is suitable for inclusion in the main code base

'''Frequent Objection #1:''' ''But I don't have time to do a qualification task!'' Then how do we know you will have time to work on your task during the summer? The qualification tasks are selected to be fairly trivial by FFmpeg standards and should not be too difficult for a prospective FFmpeg contributor. If they ''are'' too difficult, maybe FFmpeg is not the project for you. Also, be encouraged by the fact that the app review period comes after the application submission deadline; i.e., you can work on a qualification task ''after'' you submit an application for FFmpeg. But you will not be considered for an SoC project slot unless you have satisfactorily completed a qualification task.

'''Process:''' If you are interested in applying for FFmpeg's Summer of Code and, by extension, interested in working on a qualification task, the first step is to subscribe to the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list] and indicate your interest and which project you plan to work on.

=== Finish up a previous incomplete SoC project ===

Several SoC projects from previous years have not yet made it into FFmpeg. Taking any of them and finishing them up to the point that they can be included should make for a good qualification task. Check out the [[FFmpeg Summer Of Code]] overview page and look for the unfinished projects, like AMR-NB, QCELP, Dirac, TS muxer, JPEG 2000.

* Bartlomiej Wolowiec is working on finishing the EAC3 decoder [http://lists.mplayerhq.hu/pipermail/ffmpeg-soc/2008-March/002745.html].

=== Generic Colorspace system ===
This task involves adding support more than 8 bits per component (Y on 10 bits, U on 10 bits, V on 10 bits for example)
and generic simple conversion to other colorspaces.

''Does this have to do with revising FFmpeg's infrastructure? If so, then it doesn't feel like a qualification task. If it's something simpler, then the vague description does not convey that simplicity. Please expound.'' --[[User:Multimedia Mike|Multimedia Mike]] 12:56, 25 February 2008 (EST)

''I don't think so, extending PixFmt to extended structure with finegrained description like depth, range values, colorspace, sample period, and write generic simple conversion from all formats to all others, like suggested by Michael on the mailing list. Conversion routine can be a good qualification task for video encoders/decoders. What do you think ?
--[[User:Bcoudurier|Baptiste Coudurier]] 00:30, 29 February 2008 (EST)

=== Cleanup of MLP decoder ===
This task involves adding a decoder to FFmpeg to play [[Meridian Lossless Packing|MLP]] audio data. The hard work has already been done; now a volunteer needs to take the existing decoder patch and make it satisfactory for inclusion into the codebase. MLP samples referenced from the [[Meridian Lossless Packing|MLP]] Wiki page.

Latest version of the MLP patch: http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-January/040234.html

And the comments: http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-January/040251.html

Claimed by: Andy Gocke

=== Support PB frame mode for H.263i ===
Details are in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue27

=== Patch cleanup for MPEG 1 & 2 optimizations ===
Details are in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue100

=== Implement a Vivo demuxer for FFmpeg ===
Implement an FFmpeg demuxer for the [[Vivo]] file format. The best reference for understanding the format would be MPlayer's [http://svn.mplayerhq.hu/mplayer/trunk/libmpdemux/demux_viv.c?view=markup existing .viv demuxer].

This task corresponds to issue 99: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue99

''I am ready to help out with understanding MPlayer's demuxer, esp. MPlayer API stuff if necessary.
--[[User:Reimar|Reimar]] 15:46, 1 March 2008 (EST)

* Marcondes Ricarte is working on this [http://lists.mplayerhq.hu/pipermail/ffmpeg-soc/2008-March/002704.html]

=== Optimal Huffman tables for (M)JPEG ===
This task is outlined at http://guru.multimedia.cx/small-tasks-for-ffmpeg/ and is tracked in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue267

* Deep Pal [http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-March/043547.html asked] this task to be assigned to him in the ffmpeg-devel mailing list.

=== RL2 Playback System ===
This task is to implement an FFmpeg playback subsystem for [[RL2]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[RL2|The RL2 page]] contains the specs necessary to complete this task and points to downloadable samples.

:''Sascha Sommer sent a [http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-March/043598.html patch] to implement this to ffmpeg-devel.''

=== YOP Playback System ===
This task is to implement an FFmpeg playback subsystem for [[Psygnosis YOP]] files. This will entail writing a new file demuxer and video decoder, both of which are trivial by FFmpeg standards. [[Psygnosis YOP|The Psygnosis YOP page]] contains the specs necessary to complete this task and points to downloadable samples.

* Claimed by Indrani

=== BFI Playback System ===
This task is to implement an FFmpeg playback subsystem for [[BFI]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[BFI|The BFI page]] contains the specs necessary to complete this task and points to downloadable samples.

=== M95 Playback System ===
This task is to implement an FFmpeg playback subsystem for [[M95]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[M95|The M95 page]] contains the specs necessary to complete this task and points to downloadable samples.

=== SSE2 iDCT Optimization ===
Incorporate an invert discrete cosine transform for SSE2-capable CPUs. The hardest work is already done-- dig up Intel's AP-945 application programming note which will spell out precisely how to do this. Mostly, this involves adapting the ASM code for gcc AT&T syntax.

:''I will be working on this.'' - [[User:Astrange|Alexander Strange]]

=== Apple RPZA encoder ===
Clean up the patch for svn inclusion. The current code can be found from here "[[Interesting Patches]]".

=== IFF demuxer ===
Implement demuxing of 8svx audio.

=== Interesting Patches ===
There is a growing backlog of "[[Interesting Patches]]" for FFmpeg tracked on this Wiki. Each one requires a volunteer to task the initiative to clean up the patch to the satisfaction of the project leaders so that it can finally be included.

=== Some bug on the bugtracker ===
From this page you can find the bugtracker: http://ffmpeg.mplayerhq.hu/bugreports.html
Some issues can qualify as a qualification task.

=== Legacy Tasks ===
Many tasks were suggested during the 2007 season. Any task that is not marked as '''completed''' is probably fair game, but ask on the list, just to be sure: http://wiki.multimedia.cx/index.php?title=FFmpeg_Summer_Of_Code_2007#Qualification_tasks

=== Freeform Tasks ===
If you have an idea for a simple task, come and discuss it on the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel development mailing list] and the devs might approve it.

[[Category:FFmpeg]]

X264 Summer Of Code 2008

2008-03-18T01:13:45Z

Dark Shikari:

[http://wiki.videolan.org/SoC_x264 This year's x264 SoC is being handled by VideoLan.]

X264

2008-03-17T23:36:28Z

Dark Shikari: url fix

* Website: [http://www.videolan.org/developers/x264.html http://www.videolan.org/developers/x264.html]
* Fan site with lots of (mostly Win32-oriented) links and utils: [http://x264.nl http://x264.nl]

x264 is a highly successful [[H.264]] encoder. It provides a library and a simple frontend application that accepts raw YUV input, and outputs either a raw H.264 elementary stream or a [[Matroska]] or [[MP4]] file.

While its encoding speed is not as fast as most ASP encoders, the output quality is quite high. x264 managed to win a recent [http://www.doom9.org/index.html?/codecs-final-105-1.htm codec comparison by Doom9].

x264 was born in late 2003. Originally developed primarily by Laurent Aimar, since about mid-2004, the majority of the work on this encoder has come from Loren Merritt.

[[Category:Multimedia Programs]]

X264 Summer Of Code 2008

2008-03-17T20:37:55Z

Dark Shikari: adding RL names

''(Note: page copied with minor modifications from [http://wiki.videolan.org/SoC_x264 the Videolan wiki])''<br><br>
[[x264]] has loads of possibilities for [[FFmpeg Summer Of Code 2008]] projects. This is part of the FFmpeg Summer of Code 2008.

*Mentor (and author of this page): Jason Garrett-Glaser (Dark Shikari)
*Possible backup mentor: Loren Merritt (pengvado)

==Introduction to x264==
x264 is probably the most efficient, compression-wise, open source video encoder there is. It is quite competitive with commercial encoders, outclassing a large number of them.

While not actually part of ffmpeg (it has its own codebase), it is a major library used by ffmpeg, licensed under the GPL, in addition to being a standalone encoder. As the only major open-source H.264 encoder, x264 has a near-complete monopoly on H.264 encoding in the consumer world, along with being used by many major corporations, including Facebook and Google. Some companies, such as Avail Media, have in the past offered bounties on improvements to the encoder.

==x264 project ideas==
This is not at all an exhaustive list; this is just a few I thought up with. I'm willing to mentor any reasonable project on x264 to the best of my ability. I'm being pretty conservative here, so I'm picking projects that are probably not at all too ambitious for a good student. If anything, I might be underestimating the amount of work that can be done, so feel free to propose something else if you're feeling creative.
:-- Dark Shikari

===Size key===
Depends heavily on the skill and willingness to work of the student. An extremely dedicated and talented student might be able to implement MBAFF in a summer, but it is certainly not fair to expect such a thing from most students.

*Very Large: Probably too large to completed in one summer.
*Large: Probably the right size for a full-summer project.
*Medium: Probably too small. Could be combined with another project, of course.
*Small: A small project, but definitely useful, and could be part of a larger project.

===Skills needed===
These are required for all listed projects and probably anything not listed, too.
*Basic C programming.
*Basic understanding of video encoding, or at least willingness to do the appropriate reading up on the topic before the summer begins.
*Confidence in the ability to learn the following and similar topics:
:*Discrete cosine transform and similar frequency transforms
:*Motion estimation and compensation
:*Quantization and entropy encoding

==Projects==
===Fast inter refinement===
''Size: Medium to large.''

Description: Improve heuristics and decision-making for inter refinement to improve efficiency on non-insane encoding settings. This would involve various early termination heuristics along with methods of deciding which partition modes need to be searched while performing minimal actual searching on those partition modes. This would be similar to, but a vastly more in-depth analysis of what was proposed in the "Fast-Ref-Search" patch.

Difficulty: Medium

===Fast intra refinement===
''Size: Small to medium''

Description: Similar to above, but covering intra modes instead. Would probably involve considerable statistical analysis of intra mode data, along with creative solutions for improved RDO refinement. We already have some ideas on this one, but haven't implemented any of them.

Difficulty: Medium

===RDO B-frame decision===
''Size: Medium to large''

Description: x264's biggest weakness is its B-frame decision algorithm, which can often be extremely subtopimal, with OPSNR losses as high as 1db in some cases. Improving this would drastically increase the effectiveness of the encoder.

Difficulty: Medium-high

===Other possible projects===
Anything here (and not here) can potentially be picked from at the request of a student.

*Assembly optimizations of any sort
:*Extra skills: Assembly coding
:*Difficulty: Medium
:*Examples:
::*Port cacheline split to the motion compensation code for increased speed (this could further be used to improve ffh264's decoding).
::*Assembly-optimize some things that haven't been already.
::*Port some MMX assembly to SSE where it seems useful.
::*Play around with potential SSE4 optimizations.

*Psychovisual optimizations for mode decision and quantization (e.g. QNS)
:*Extra skills: Creativity and perhaps some understanding of DCT/Fourier math.
:*Difficulty: Medium-high
:*Examples:
::*SSIM-QNS optimization?
::*Adaptive deadzone?
::*Adaptive lambda?

*Implementing MBAFF or PicAFF (potentially too difficult for a SoC project, however)
:*Difficulty: Very high

*Fast RD optimization using heuristics
:*Extra skills: Reading lots of IEEE papers
:*Difficulty: Medium

*Motion search improvements
:*Difficulty: Medium

*Anything else reasonable, honestly. There's all sorts of ideas floating around.

==Contact info==
If you are interested, drop by #ffmpeg-devel, #ffmpeg, #x264, or #x264dev on Freenode.

FFmpeg Summer Of Code 2008

2008-03-17T20:37:07Z

Dark Shikari: /* x264 Improvements */

Google is sponsoring their fourth annual [http://code.google.com/soc/2008/ Summer of Code] for the summer of 2008. This entails paying students for working on open source projects. FFmpeg has been a participant in the 2006 and 2007 seasons. Visit the main [[FFmpeg Summer Of Code]] page for information on past seasons.

FFmpeg has been selected to participate in GSoC 2008. This page discusses possible project ideas and status for the Google Summer of Code 2008 season as it pertains to FFmpeg.

The administrator for the FFmpeg Summer of Code is Mike Melanson, a.k.a. [[User:Multimedia Mike|Multimedia Mike]]. His email address is mike -=at=- multimedia.cx.

'''If you are a student''' who wishes to be '''involved with a FFmpeg GSoC''' project, one of the first and best steps you can take is to subscribe to the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list], sooner rather than later, and indicate your interest. In the past, we have weighted our selection decisions by how involved a prospective student is. And remember to read the part of this page dealing with qualification tasks since you '''absolutely must''' complete a qualification task to be eligible for a FFmpeg SoC project. No qualification task, no project. No exceptions.

== Current Status ==
* '''Next Big Date:''' March 24, 2008: Students may submit applications through Google
* March 17, 2008: Google is scheduled to announce selected projects; ''FFmpeg is selected''
* March 3, 2008: Submitted FFmpeg project application
* February 20, 2008: Created page

== Schedule ==
Official timeline: http://code.google.com/soc/2008/faqs.html#0.1_timeline
* March 3-12, 2008: Open source organizations may apply to the Google Summer of Code program.
* March 17, 2008: Google is scheduled to announce accepted organizations at: http://code.google.com/soc/
* March 24-31, 2008: Students may submit applications for various Google Summer of Code projects.

== Application Process ==
The student application process for 2008 will be as rigorous, if not more so, than in 2007.

[http://code.google.com/opensource/gsoc/2008/faqs.html#0.1_timeline From the formal timeline]:
* March 24, 2008: Student application period opens.
* March 31, 2008: Student application deadline.
* April 11, 2008: Final decisions are made.

All students who wish to be eligible for a GSoC FFmpeg project '''must''' successfully complete a qualification task. A student may submit an application before completing their task and they will have until April 11, 2008 to finish a qualification task. It is ill-advised to wait until the last minute, though. You must ''complete'' the task, which involves getting code approved for submission to source control, which takes many iterations over many days for most people. Further, we like people who show initiative earlier than later.

== 1st Tier Project Proposals ==
1st tier project proposals are project ideas that are reasonably well defined '''AND''' have a mentor volunteered.

==== G.729 Encoder ====
* Specification: http://www.itu.int/rec/T-REC-G.729/e
''Mentor: Benjamin Larsson''

==== G.723.1 Decoder ====
* Specification: http://www.itu.int/rec/T-REC-G.723.1/en
''Mentor: Benjamin Larsson''

==== G.723.1 Encoder ====
* Specification: http://www.itu.int/rec/T-REC-G.723.1/en
''Mentor: Benjamin Larsson''

=== DTS Encoder ===
* Specification: http://wiki.multimedia.cx/index.php?title=Mirror
* Sample files: http://samples.mplayerhq.hu/A-codecs/DTS/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* There will be an existing encoder to extend, it will only produce 2 channel 44.1kHz streams.
* Primary goal: Encoder that can produce multi sample rate and multi channel files. Simple rate control. Wav and raw muxing support. Wav dts auto detection when decoding.
* Secondary goal: Techniques from specification implemented, optimal codebook usage, vector quantization, simple psycho acustics.
* Third goal: Advanced psycho acoustics.
''Mentor: Benjamin Larsson''

=== Nellymoser Encoder ===
* Specification: http://svn.mplayerhq.hu/ffmpeg/trunk/libavcodec/nellymoserdec.c?revision=11708&view=markup
* Sample files: http://samples.mplayerhq.hu/A-codecs/Nelly_Moser/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* Primary goal: Dumb bitstream compatible encoder
* Secondary goal: Simple psycoacousics implemented
''Mentor: Benjamin Larsson''

=== AAC-LC Encoder ===
* Sample files: http://samples.mplayerhq.hu/A-codecs/AAC/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* Primary goal: Dumb bitstream compatible encoder with flexible framework for a serious psychoacoustic implementation
''Mentor: Benjamin Larsson''
''Co-Mentor: Anderas Öman''

=== VP3/Theora Encoder ===
* Clearly defined task
* Primary goal: Encode video sequences such that they can be decoded by a VP3 decoder first, and then a standard Theora decoder.
''Mentor: Mike Melanson''

=== MXF muxer ===
* Specifications: SMPTE 377M
* Clearly defined task
''Mentor: Baptiste Coudurier''

=== MVC decoder ===
* Create an independent FFmpeg decoder for the [[Nokia MVC]] codec
* Very clearly defined task
* ''Mentor: Michael Niedermayer''

=== Apple Lossless Encoder ===
* Samples: http://samples.mplayerhq.hu/A-codecs/lossless/ALAC/
* Decoder: http://svn.mplayerhq.hu/ffmpeg/trunk/libavcodec/alac.c?&view=markup
* Encoder that works on Linux with Wine: http://www.dbpoweramp.com/dmc.htm
* Primary goal: Encode files which will decode losslessly using the FFmpeg ALAC decoder.
* Secondary goal: Make sure encoded files will decode losslessly with iTunes and play on an iPod.
* Reuse as much code as possible from other FFmpeg encoders, namely FLAC since it is a similar codec.
* Specifically, reuse the LPC code from FLAC and make it more generic so it can be shared with various speech codecs as well.
* As time allows, experiment with different parts of the codec to push the boundaries of FFmpeg's decoder and of the format itself.
Also see [[ALAC]] and issue [https://roundup.mplayerhq.hu/roundup/ffmpeg/issue82 #82].

''Mentor: Justin Ruggles''

=== Snow Job ===
This task involves finishing work on the [[Snow]] video codec to bring it to 1.0 quality.
* Document the whole Snow algorithm
* Fix all Snow related bugs on roundup
* faster halfpel interpolation (issue183)
* Try a different transform like an lapped biorthogonal transform instead of the wavelet (this could be better or worse only trying can tell ...)
* anything in [http://svn.mplayerhq.hu/ffmpeg/trunk/doc/TODO?view=co doc/TODO] about Snow and [http://svn.mplayerhq.hu/ffmpeg/trunk/doc/snow.txt?view=co snow.txt/TODO]
* anything else which might improve Snow quality per bitrate
''(The idea here is that the goal would be, do as much as the time allows, though we should decide on some minimum as all above is clearly not doable within the time)

''Mentor: Michael Niedermayer''

=== x264 Improvements ===
This task involve various possible improvements to the [[x264]] video encoder. Full details can be found on [[X264_Summer_Of_Code_2008|x264's Summer of Code page]].

''Mentor: Jason Garrett-Glaser (Dark Shikari)''

== 2nd Tier Project Proposals ==
All that separates these proposals from their 1st tier brethren is a mentor. If you are particularly passionate about one of these tasks, perhaps you should attach your name to it. ''(Email me if you want to discuss it or need access to the Wiki. --[[User:Multimedia Mike|Multimedia Mike]] 21:58, 1 March 2008 (EST))''

==== GUI for FFmpeg ====
Build a gui for the libs of FFmpeg. The main objective in this task is to extent the codecs and formats to support querying of features and good defaults. The actual GUI should just be a simple skeleton with support for encoding of multiple files. Most of the work will be done in the libs.

==== Port FFmpeg to Visual Studio ====
Create a full working port including inline assembly.

==== Optimize FFT routines ====
Port djbfft and rework the fft framework in FFmpeg. This task can include a fixedpoint port and SIMD optimizations.

==== GSM Decoder ====
* Specification + sample implementation: http://kbs.cs.tu-berlin.de/~jutta/toast.html
* Samples: http://samples.mplayerhq.hu/A-codecs/GSM/
Also see [[GSM]].

==== AMR-WB Decoder ====
* Specification: http://www.3gpp.org/ftp/Specs/html-info/26-series.htm
* Samples: http://samples.mplayerhq.hu/A-codecs/amr/
Also see [[AMR]].

==== AMR-NB Encoder ====
* Specification: http://www.3gpp.org/ftp/Specs/html-info/26-series.htm
* Samples: http://samples.mplayerhq.hu/A-codecs/amr/
Also see [[AMR]].

==== Speex Decoder ====
* Specification: http://speex.org/docs/
* Samples: http://samples.mplayerhq.hu/A-codecs/speex/
Also see [[Speex]].

=== WMV3 Encoder ===
* Clearly defined task
* Primary goal: Encode video sequences such that they can be decoded by a Windows Media player.

This could either be done by improving [[Interesting Patches#WMV3 encoder by Denis Fortin|this patch]] or by writing the encoder from scratch.

=== Better handling of audio in libavcodec ===
* Info: http://wiki.multimedia.cx/index.php?title=Ffmpeg_audio_api
* Loosely defined task

=== LGPL reimplementation of GPL sws_scale parts ===
* Loosely defined task
* Primary goal: LGPL licensed sws_scale
* Secondary goal: removal of lavc scaler

=== Freeform Proposal ===
If you think you have a good idea for a FFmpeg Summer of Code project, propose it on the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list]. We will discuss it from there.

== Qualification Tasks ==
Many students apply for the Google Summer of Code and wish to work on a sexy multimedia project such as FFmpeg. All students will claim to be hard workers but we need a method of determining which students have a higher probability for success. Thus, we developed the qualification system during the 2007 season and will be enforcing the same system this year. A student must successfully complete a qualification task in order to be considered for an FFmpeg SoC project. In doing so, a student demonstrates that they:

* are willing to commit some time during the Summer of Code application review period in order to prove themselves
* can code C satisfactorily and with the same general style expected of the FFmpeg codebase
* can wrap their head around the code base
* can interact with the FFmpeg development mailing list
* can accept feedback and revise the code until it is suitable for inclusion in the main code base

'''Frequent Objection #1:''' ''But I don't have time to do a qualification task!'' Then how do we know you will have time to work on your task during the summer? The qualification tasks are selected to be fairly trivial by FFmpeg standards and should not be too difficult for a prospective FFmpeg contributor. If they ''are'' too difficult, maybe FFmpeg is not the project for you. Also, be encouraged by the fact that the app review period comes after the application submission deadline; i.e., you can work on a qualification task ''after'' you submit an application for FFmpeg. But you will not be considered for an SoC project slot unless you have satisfactorily completed a qualification task.

'''Process:''' If you are interested in applying for FFmpeg's Summer of Code and, by extension, interested in working on a qualification task, the first step is to subscribe to the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list] and indicate your interest and which project you plan to work on.

=== Finish up a previous incomplete SoC project ===

Several SoC projects from previous years have not yet made it into FFmpeg. Taking any of them and finishing them up to the point that they can be included should make for a good qualification task. Check out the [[FFmpeg Summer Of Code]] overview page and look for the unfinished projects, like AMR-NB, QCELP, Dirac, TS muxer, JPEG 2000.

* Bartlomiej Wolowiec is working on finishing the EAC3 decoder [http://lists.mplayerhq.hu/pipermail/ffmpeg-soc/2008-March/002745.html].

=== Generic Colorspace system ===
This task involves adding support more than 8 bits per component (Y on 10 bits, U on 10 bits, V on 10 bits for example)
and generic simple conversion to other colorspaces.

''Does this have to do with revising FFmpeg's infrastructure? If so, then it doesn't feel like a qualification task. If it's something simpler, then the vague description does not convey that simplicity. Please expound.'' --[[User:Multimedia Mike|Multimedia Mike]] 12:56, 25 February 2008 (EST)

''I don't think so, extending PixFmt to extended structure with finegrained description like depth, range values, colorspace, sample period, and write generic simple conversion from all formats to all others, like suggested by Michael on the mailing list. Conversion routine can be a good qualification task for video encoders/decoders. What do you think ?
--[[User:Bcoudurier|Baptiste Coudurier]] 00:30, 29 February 2008 (EST)

=== Cleanup of MLP decoder ===
This task involves adding a decoder to FFmpeg to play [[Meridian Lossless Packing|MLP]] audio data. The hard work has already been done; now a volunteer needs to take the existing decoder patch and make it satisfactory for inclusion into the codebase. MLP samples referenced from the [[Meridian Lossless Packing|MLP]] Wiki page.

Latest version of the MLP patch: http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-January/040234.html

And the comments: http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-January/040251.html

Claimed by: Andy Gocke

=== Support PB frame mode for H.263i ===
Details are in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue27

=== Patch cleanup for MPEG 1 & 2 optimizations ===
Details are in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue100

=== Implement a Vivo demuxer for FFmpeg ===
Implement an FFmpeg demuxer for the [[Vivo]] file format. The best reference for understanding the format would be MPlayer's [http://svn.mplayerhq.hu/mplayer/trunk/libmpdemux/demux_viv.c?view=markup existing .viv demuxer].

This task corresponds to issue 99: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue99

''I am ready to help out with understanding MPlayer's demuxer, esp. MPlayer API stuff if necessary.
--[[User:Reimar|Reimar]] 15:46, 1 March 2008 (EST)

* Marcondes Ricarte is working on this [http://lists.mplayerhq.hu/pipermail/ffmpeg-soc/2008-March/002704.html]

=== Optimal Huffman tables for (M)JPEG ===
This task is outlined at http://guru.multimedia.cx/small-tasks-for-ffmpeg/ and is tracked in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue267

* Deep Pal [http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-March/043547.html asked] this task to be assigned to him in the ffmpeg-devel mailing list.

=== RL2 Playback System ===
This task is to implement an FFmpeg playback subsystem for [[RL2]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[RL2|The RL2 page]] contains the specs necessary to complete this task and points to downloadable samples.

:''Sascha Sommer sent a [http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-March/043598.html patch] to implement this to ffmpeg-devel.''

=== YOP Playback System ===
This task is to implement an FFmpeg playback subsystem for [[Psygnosis YOP]] files. This will entail writing a new file demuxer and video decoder, both of which are trivial by FFmpeg standards. [[Psygnosis YOP|The Psygnosis YOP page]] contains the specs necessary to complete this task and points to downloadable samples.

* Claimed by Indrani

=== BFI Playback System ===
This task is to implement an FFmpeg playback subsystem for [[BFI]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[BFI|The BFI page]] contains the specs necessary to complete this task and points to downloadable samples.

=== M95 Playback System ===
This task is to implement an FFmpeg playback subsystem for [[M95]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[M95|The M95 page]] contains the specs necessary to complete this task and points to downloadable samples.

=== SSE2 iDCT Optimization ===
Incorporate an invert discrete cosine transform for SSE2-capable CPUs. The hardest work is already done-- dig up Intel's AP-945 application programming note which will spell out precisely how to do this. Mostly, this involves adapting the ASM code for gcc AT&T syntax.

:''I will be working on this.'' - [[User:Astrange|Alexander Strange]]

=== Apple RPZA encoder ===
Clean up the patch for svn inclusion. The current code can be found from here "[[Interesting Patches]]".

=== IFF demuxer ===
Implement demuxing of 8svx audio.

=== Interesting Patches ===
There is a growing backlog of "[[Interesting Patches]]" for FFmpeg tracked on this Wiki. Each one requires a volunteer to task the initiative to clean up the patch to the satisfaction of the project leaders so that it can finally be included.

=== Some bug on the bugtracker ===
From this page you can find the bugtracker: http://ffmpeg.mplayerhq.hu/bugreports.html
Some issues can qualify as a qualification task.

=== Legacy Tasks ===
Many tasks were suggested during the 2007 season. Any task that is not marked as '''completed''' is probably fair game, but ask on the list, just to be sure: http://wiki.multimedia.cx/index.php?title=FFmpeg_Summer_Of_Code_2007#Qualification_tasks

=== Freeform Tasks ===
If you have an idea for a simple task, come and discuss it on the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel development mailing list] and the devs might approve it.

[[Category:FFmpeg]]

FFmpeg Summer Of Code 2008

2008-03-17T20:34:08Z

Dark Shikari: /* 1st Tier Project Proposals */

Google is sponsoring their fourth annual [http://code.google.com/soc/2008/ Summer of Code] for the summer of 2008. This entails paying students for working on open source projects. FFmpeg has been a participant in the 2006 and 2007 seasons. Visit the main [[FFmpeg Summer Of Code]] page for information on past seasons.

FFmpeg has been selected to participate in GSoC 2008. This page discusses possible project ideas and status for the Google Summer of Code 2008 season as it pertains to FFmpeg.

The administrator for the FFmpeg Summer of Code is Mike Melanson, a.k.a. [[User:Multimedia Mike|Multimedia Mike]]. His email address is mike -=at=- multimedia.cx.

'''If you are a student''' who wishes to be '''involved with a FFmpeg GSoC''' project, one of the first and best steps you can take is to subscribe to the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list], sooner rather than later, and indicate your interest. In the past, we have weighted our selection decisions by how involved a prospective student is. And remember to read the part of this page dealing with qualification tasks since you '''absolutely must''' complete a qualification task to be eligible for a FFmpeg SoC project. No qualification task, no project. No exceptions.

== Current Status ==
* '''Next Big Date:''' March 24, 2008: Students may submit applications through Google
* March 17, 2008: Google is scheduled to announce selected projects; ''FFmpeg is selected''
* March 3, 2008: Submitted FFmpeg project application
* February 20, 2008: Created page

== Schedule ==
Official timeline: http://code.google.com/soc/2008/faqs.html#0.1_timeline
* March 3-12, 2008: Open source organizations may apply to the Google Summer of Code program.
* March 17, 2008: Google is scheduled to announce accepted organizations at: http://code.google.com/soc/
* March 24-31, 2008: Students may submit applications for various Google Summer of Code projects.

== Application Process ==
The student application process for 2008 will be as rigorous, if not more so, than in 2007.

[http://code.google.com/opensource/gsoc/2008/faqs.html#0.1_timeline From the formal timeline]:
* March 24, 2008: Student application period opens.
* March 31, 2008: Student application deadline.
* April 11, 2008: Final decisions are made.

All students who wish to be eligible for a GSoC FFmpeg project '''must''' successfully complete a qualification task. A student may submit an application before completing their task and they will have until April 11, 2008 to finish a qualification task. It is ill-advised to wait until the last minute, though. You must ''complete'' the task, which involves getting code approved for submission to source control, which takes many iterations over many days for most people. Further, we like people who show initiative earlier than later.

== 1st Tier Project Proposals ==
1st tier project proposals are project ideas that are reasonably well defined '''AND''' have a mentor volunteered.

==== G.729 Encoder ====
* Specification: http://www.itu.int/rec/T-REC-G.729/e
''Mentor: Benjamin Larsson''

==== G.723.1 Decoder ====
* Specification: http://www.itu.int/rec/T-REC-G.723.1/en
''Mentor: Benjamin Larsson''

==== G.723.1 Encoder ====
* Specification: http://www.itu.int/rec/T-REC-G.723.1/en
''Mentor: Benjamin Larsson''

=== DTS Encoder ===
* Specification: http://wiki.multimedia.cx/index.php?title=Mirror
* Sample files: http://samples.mplayerhq.hu/A-codecs/DTS/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* There will be an existing encoder to extend, it will only produce 2 channel 44.1kHz streams.
* Primary goal: Encoder that can produce multi sample rate and multi channel files. Simple rate control. Wav and raw muxing support. Wav dts auto detection when decoding.
* Secondary goal: Techniques from specification implemented, optimal codebook usage, vector quantization, simple psycho acustics.
* Third goal: Advanced psycho acoustics.
''Mentor: Benjamin Larsson''

=== Nellymoser Encoder ===
* Specification: http://svn.mplayerhq.hu/ffmpeg/trunk/libavcodec/nellymoserdec.c?revision=11708&view=markup
* Sample files: http://samples.mplayerhq.hu/A-codecs/Nelly_Moser/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* Primary goal: Dumb bitstream compatible encoder
* Secondary goal: Simple psycoacousics implemented
''Mentor: Benjamin Larsson''

=== AAC-LC Encoder ===
* Sample files: http://samples.mplayerhq.hu/A-codecs/AAC/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* Primary goal: Dumb bitstream compatible encoder with flexible framework for a serious psychoacoustic implementation
''Mentor: Benjamin Larsson''
''Co-Mentor: Anderas Öman''

=== VP3/Theora Encoder ===
* Clearly defined task
* Primary goal: Encode video sequences such that they can be decoded by a VP3 decoder first, and then a standard Theora decoder.
''Mentor: Mike Melanson''

=== MXF muxer ===
* Specifications: SMPTE 377M
* Clearly defined task
''Mentor: Baptiste Coudurier''

=== MVC decoder ===
* Create an independent FFmpeg decoder for the [[Nokia MVC]] codec
* Very clearly defined task
* ''Mentor: Michael Niedermayer''

=== Apple Lossless Encoder ===
* Samples: http://samples.mplayerhq.hu/A-codecs/lossless/ALAC/
* Decoder: http://svn.mplayerhq.hu/ffmpeg/trunk/libavcodec/alac.c?&view=markup
* Encoder that works on Linux with Wine: http://www.dbpoweramp.com/dmc.htm
* Primary goal: Encode files which will decode losslessly using the FFmpeg ALAC decoder.
* Secondary goal: Make sure encoded files will decode losslessly with iTunes and play on an iPod.
* Reuse as much code as possible from other FFmpeg encoders, namely FLAC since it is a similar codec.
* Specifically, reuse the LPC code from FLAC and make it more generic so it can be shared with various speech codecs as well.
* As time allows, experiment with different parts of the codec to push the boundaries of FFmpeg's decoder and of the format itself.
Also see [[ALAC]] and issue [https://roundup.mplayerhq.hu/roundup/ffmpeg/issue82 #82].

''Mentor: Justin Ruggles''

=== Snow Job ===
This task involves finishing work on the [[Snow]] video codec to bring it to 1.0 quality.
* Document the whole Snow algorithm
* Fix all Snow related bugs on roundup
* faster halfpel interpolation (issue183)
* Try a different transform like an lapped biorthogonal transform instead of the wavelet (this could be better or worse only trying can tell ...)
* anything in [http://svn.mplayerhq.hu/ffmpeg/trunk/doc/TODO?view=co doc/TODO] about Snow and [http://svn.mplayerhq.hu/ffmpeg/trunk/doc/snow.txt?view=co snow.txt/TODO]
* anything else which might improve Snow quality per bitrate
''(The idea here is that the goal would be, do as much as the time allows, though we should decide on some minimum as all above is clearly not doable within the time)

''Mentor: Michael Niedermayer''

=== x264 Improvements ===
This task involve various possible improvements to the [[x264]] video encoder. Full details can be found on [[X264_Summer_Of_Code_2008|x264's Summer of Code page]].

''Mentor: Dark Shikari''

== 2nd Tier Project Proposals ==
All that separates these proposals from their 1st tier brethren is a mentor. If you are particularly passionate about one of these tasks, perhaps you should attach your name to it. ''(Email me if you want to discuss it or need access to the Wiki. --[[User:Multimedia Mike|Multimedia Mike]] 21:58, 1 March 2008 (EST))''

==== GUI for FFmpeg ====
Build a gui for the libs of FFmpeg. The main objective in this task is to extent the codecs and formats to support querying of features and good defaults. The actual GUI should just be a simple skeleton with support for encoding of multiple files. Most of the work will be done in the libs.

==== Port FFmpeg to Visual Studio ====
Create a full working port including inline assembly.

==== Optimize FFT routines ====
Port djbfft and rework the fft framework in FFmpeg. This task can include a fixedpoint port and SIMD optimizations.

==== GSM Decoder ====
* Specification + sample implementation: http://kbs.cs.tu-berlin.de/~jutta/toast.html
* Samples: http://samples.mplayerhq.hu/A-codecs/GSM/
Also see [[GSM]].

==== AMR-WB Decoder ====
* Specification: http://www.3gpp.org/ftp/Specs/html-info/26-series.htm
* Samples: http://samples.mplayerhq.hu/A-codecs/amr/
Also see [[AMR]].

==== AMR-NB Encoder ====
* Specification: http://www.3gpp.org/ftp/Specs/html-info/26-series.htm
* Samples: http://samples.mplayerhq.hu/A-codecs/amr/
Also see [[AMR]].

==== Speex Decoder ====
* Specification: http://speex.org/docs/
* Samples: http://samples.mplayerhq.hu/A-codecs/speex/
Also see [[Speex]].

=== WMV3 Encoder ===
* Clearly defined task
* Primary goal: Encode video sequences such that they can be decoded by a Windows Media player.

This could either be done by improving [[Interesting Patches#WMV3 encoder by Denis Fortin|this patch]] or by writing the encoder from scratch.

=== Better handling of audio in libavcodec ===
* Info: http://wiki.multimedia.cx/index.php?title=Ffmpeg_audio_api
* Loosely defined task

=== LGPL reimplementation of GPL sws_scale parts ===
* Loosely defined task
* Primary goal: LGPL licensed sws_scale
* Secondary goal: removal of lavc scaler

=== Freeform Proposal ===
If you think you have a good idea for a FFmpeg Summer of Code project, propose it on the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list]. We will discuss it from there.

== Qualification Tasks ==
Many students apply for the Google Summer of Code and wish to work on a sexy multimedia project such as FFmpeg. All students will claim to be hard workers but we need a method of determining which students have a higher probability for success. Thus, we developed the qualification system during the 2007 season and will be enforcing the same system this year. A student must successfully complete a qualification task in order to be considered for an FFmpeg SoC project. In doing so, a student demonstrates that they:

* are willing to commit some time during the Summer of Code application review period in order to prove themselves
* can code C satisfactorily and with the same general style expected of the FFmpeg codebase
* can wrap their head around the code base
* can interact with the FFmpeg development mailing list
* can accept feedback and revise the code until it is suitable for inclusion in the main code base

'''Frequent Objection #1:''' ''But I don't have time to do a qualification task!'' Then how do we know you will have time to work on your task during the summer? The qualification tasks are selected to be fairly trivial by FFmpeg standards and should not be too difficult for a prospective FFmpeg contributor. If they ''are'' too difficult, maybe FFmpeg is not the project for you. Also, be encouraged by the fact that the app review period comes after the application submission deadline; i.e., you can work on a qualification task ''after'' you submit an application for FFmpeg. But you will not be considered for an SoC project slot unless you have satisfactorily completed a qualification task.

'''Process:''' If you are interested in applying for FFmpeg's Summer of Code and, by extension, interested in working on a qualification task, the first step is to subscribe to the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list] and indicate your interest and which project you plan to work on.

=== Finish up a previous incomplete SoC project ===

Several SoC projects from previous years have not yet made it into FFmpeg. Taking any of them and finishing them up to the point that they can be included should make for a good qualification task. Check out the [[FFmpeg Summer Of Code]] overview page and look for the unfinished projects, like AMR-NB, QCELP, Dirac, TS muxer, JPEG 2000.

* Bartlomiej Wolowiec is working on finishing the EAC3 decoder [http://lists.mplayerhq.hu/pipermail/ffmpeg-soc/2008-March/002745.html].

=== Generic Colorspace system ===
This task involves adding support more than 8 bits per component (Y on 10 bits, U on 10 bits, V on 10 bits for example)
and generic simple conversion to other colorspaces.

''Does this have to do with revising FFmpeg's infrastructure? If so, then it doesn't feel like a qualification task. If it's something simpler, then the vague description does not convey that simplicity. Please expound.'' --[[User:Multimedia Mike|Multimedia Mike]] 12:56, 25 February 2008 (EST)

''I don't think so, extending PixFmt to extended structure with finegrained description like depth, range values, colorspace, sample period, and write generic simple conversion from all formats to all others, like suggested by Michael on the mailing list. Conversion routine can be a good qualification task for video encoders/decoders. What do you think ?
--[[User:Bcoudurier|Baptiste Coudurier]] 00:30, 29 February 2008 (EST)

=== Cleanup of MLP decoder ===
This task involves adding a decoder to FFmpeg to play [[Meridian Lossless Packing|MLP]] audio data. The hard work has already been done; now a volunteer needs to take the existing decoder patch and make it satisfactory for inclusion into the codebase. MLP samples referenced from the [[Meridian Lossless Packing|MLP]] Wiki page.

Latest version of the MLP patch: http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-January/040234.html

And the comments: http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-January/040251.html

Claimed by: Andy Gocke

=== Support PB frame mode for H.263i ===
Details are in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue27

=== Patch cleanup for MPEG 1 & 2 optimizations ===
Details are in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue100

=== Implement a Vivo demuxer for FFmpeg ===
Implement an FFmpeg demuxer for the [[Vivo]] file format. The best reference for understanding the format would be MPlayer's [http://svn.mplayerhq.hu/mplayer/trunk/libmpdemux/demux_viv.c?view=markup existing .viv demuxer].

This task corresponds to issue 99: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue99

''I am ready to help out with understanding MPlayer's demuxer, esp. MPlayer API stuff if necessary.
--[[User:Reimar|Reimar]] 15:46, 1 March 2008 (EST)

* Marcondes Ricarte is working on this [http://lists.mplayerhq.hu/pipermail/ffmpeg-soc/2008-March/002704.html]

=== Optimal Huffman tables for (M)JPEG ===
This task is outlined at http://guru.multimedia.cx/small-tasks-for-ffmpeg/ and is tracked in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue267

* Deep Pal [http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-March/043547.html asked] this task to be assigned to him in the ffmpeg-devel mailing list.

=== RL2 Playback System ===
This task is to implement an FFmpeg playback subsystem for [[RL2]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[RL2|The RL2 page]] contains the specs necessary to complete this task and points to downloadable samples.

:''Sascha Sommer sent a [http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-March/043598.html patch] to implement this to ffmpeg-devel.''

=== YOP Playback System ===
This task is to implement an FFmpeg playback subsystem for [[Psygnosis YOP]] files. This will entail writing a new file demuxer and video decoder, both of which are trivial by FFmpeg standards. [[Psygnosis YOP|The Psygnosis YOP page]] contains the specs necessary to complete this task and points to downloadable samples.

* Claimed by Indrani

=== BFI Playback System ===
This task is to implement an FFmpeg playback subsystem for [[BFI]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[BFI|The BFI page]] contains the specs necessary to complete this task and points to downloadable samples.

=== M95 Playback System ===
This task is to implement an FFmpeg playback subsystem for [[M95]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[M95|The M95 page]] contains the specs necessary to complete this task and points to downloadable samples.

=== SSE2 iDCT Optimization ===
Incorporate an invert discrete cosine transform for SSE2-capable CPUs. The hardest work is already done-- dig up Intel's AP-945 application programming note which will spell out precisely how to do this. Mostly, this involves adapting the ASM code for gcc AT&T syntax.

:''I will be working on this.'' - [[User:Astrange|Alexander Strange]]

=== Apple RPZA encoder ===
Clean up the patch for svn inclusion. The current code can be found from here "[[Interesting Patches]]".

=== IFF demuxer ===
Implement demuxing of 8svx audio.

=== Interesting Patches ===
There is a growing backlog of "[[Interesting Patches]]" for FFmpeg tracked on this Wiki. Each one requires a volunteer to task the initiative to clean up the patch to the satisfaction of the project leaders so that it can finally be included.

=== Some bug on the bugtracker ===
From this page you can find the bugtracker: http://ffmpeg.mplayerhq.hu/bugreports.html
Some issues can qualify as a qualification task.

=== Legacy Tasks ===
Many tasks were suggested during the 2007 season. Any task that is not marked as '''completed''' is probably fair game, but ask on the list, just to be sure: http://wiki.multimedia.cx/index.php?title=FFmpeg_Summer_Of_Code_2007#Qualification_tasks

=== Freeform Tasks ===
If you have an idea for a simple task, come and discuss it on the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel development mailing list] and the devs might approve it.

[[Category:FFmpeg]]

FFmpeg Summer Of Code 2008

2008-03-17T20:33:44Z

Dark Shikari: /* 1st Tier Project Proposals */

Google is sponsoring their fourth annual [http://code.google.com/soc/2008/ Summer of Code] for the summer of 2008. This entails paying students for working on open source projects. FFmpeg has been a participant in the 2006 and 2007 seasons. Visit the main [[FFmpeg Summer Of Code]] page for information on past seasons.

FFmpeg has been selected to participate in GSoC 2008. This page discusses possible project ideas and status for the Google Summer of Code 2008 season as it pertains to FFmpeg.

The administrator for the FFmpeg Summer of Code is Mike Melanson, a.k.a. [[User:Multimedia Mike|Multimedia Mike]]. His email address is mike -=at=- multimedia.cx.

'''If you are a student''' who wishes to be '''involved with a FFmpeg GSoC''' project, one of the first and best steps you can take is to subscribe to the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list], sooner rather than later, and indicate your interest. In the past, we have weighted our selection decisions by how involved a prospective student is. And remember to read the part of this page dealing with qualification tasks since you '''absolutely must''' complete a qualification task to be eligible for a FFmpeg SoC project. No qualification task, no project. No exceptions.

== Current Status ==
* '''Next Big Date:''' March 24, 2008: Students may submit applications through Google
* March 17, 2008: Google is scheduled to announce selected projects; ''FFmpeg is selected''
* March 3, 2008: Submitted FFmpeg project application
* February 20, 2008: Created page

== Schedule ==
Official timeline: http://code.google.com/soc/2008/faqs.html#0.1_timeline
* March 3-12, 2008: Open source organizations may apply to the Google Summer of Code program.
* March 17, 2008: Google is scheduled to announce accepted organizations at: http://code.google.com/soc/
* March 24-31, 2008: Students may submit applications for various Google Summer of Code projects.

== Application Process ==
The student application process for 2008 will be as rigorous, if not more so, than in 2007.

[http://code.google.com/opensource/gsoc/2008/faqs.html#0.1_timeline From the formal timeline]:
* March 24, 2008: Student application period opens.
* March 31, 2008: Student application deadline.
* April 11, 2008: Final decisions are made.

All students who wish to be eligible for a GSoC FFmpeg project '''must''' successfully complete a qualification task. A student may submit an application before completing their task and they will have until April 11, 2008 to finish a qualification task. It is ill-advised to wait until the last minute, though. You must ''complete'' the task, which involves getting code approved for submission to source control, which takes many iterations over many days for most people. Further, we like people who show initiative earlier than later.

== 1st Tier Project Proposals ==
1st tier project proposals are project ideas that are reasonably well defined '''AND''' have a mentor volunteered.

==== G.729 Encoder ====
* Specification: http://www.itu.int/rec/T-REC-G.729/e
''Mentor: Benjamin Larsson''

==== G.723.1 Decoder ====
* Specification: http://www.itu.int/rec/T-REC-G.723.1/en
''Mentor: Benjamin Larsson''

==== G.723.1 Encoder ====
* Specification: http://www.itu.int/rec/T-REC-G.723.1/en
''Mentor: Benjamin Larsson''

=== DTS Encoder ===
* Specification: http://wiki.multimedia.cx/index.php?title=Mirror
* Sample files: http://samples.mplayerhq.hu/A-codecs/DTS/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* There will be an existing encoder to extend, it will only produce 2 channel 44.1kHz streams.
* Primary goal: Encoder that can produce multi sample rate and multi channel files. Simple rate control. Wav and raw muxing support. Wav dts auto detection when decoding.
* Secondary goal: Techniques from specification implemented, optimal codebook usage, vector quantization, simple psycho acustics.
* Third goal: Advanced psycho acoustics.
''Mentor: Benjamin Larsson''

=== Nellymoser Encoder ===
* Specification: http://svn.mplayerhq.hu/ffmpeg/trunk/libavcodec/nellymoserdec.c?revision=11708&view=markup
* Sample files: http://samples.mplayerhq.hu/A-codecs/Nelly_Moser/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* Primary goal: Dumb bitstream compatible encoder
* Secondary goal: Simple psycoacousics implemented
''Mentor: Benjamin Larsson''

=== AAC-LC Encoder ===
* Sample files: http://samples.mplayerhq.hu/A-codecs/AAC/
* Qualification: TBD
* Prerequisite: Filterbanks (Sigsys)
* Clearly defined task
* Primary goal: Dumb bitstream compatible encoder with flexible framework for a serious psychoacoustic implementation
''Mentor: Benjamin Larsson''
''Co-Mentor: Anderas Öman''

=== VP3/Theora Encoder ===
* Clearly defined task
* Primary goal: Encode video sequences such that they can be decoded by a VP3 decoder first, and then a standard Theora decoder.
''Mentor: Mike Melanson''

=== MXF muxer ===
* Specifications: SMPTE 377M
* Clearly defined task
''Mentor: Baptiste Coudurier''

=== MVC decoder ===
* Create an independent FFmpeg decoder for the [[Nokia MVC]] codec
* Very clearly defined task
* ''Mentor: Michael Niedermayer''

=== Apple Lossless Encoder ===
* Samples: http://samples.mplayerhq.hu/A-codecs/lossless/ALAC/
* Decoder: http://svn.mplayerhq.hu/ffmpeg/trunk/libavcodec/alac.c?&view=markup
* Encoder that works on Linux with Wine: http://www.dbpoweramp.com/dmc.htm
* Primary goal: Encode files which will decode losslessly using the FFmpeg ALAC decoder.
* Secondary goal: Make sure encoded files will decode losslessly with iTunes and play on an iPod.
* Reuse as much code as possible from other FFmpeg encoders, namely FLAC since it is a similar codec.
* Specifically, reuse the LPC code from FLAC and make it more generic so it can be shared with various speech codecs as well.
* As time allows, experiment with different parts of the codec to push the boundaries of FFmpeg's decoder and of the format itself.
Also see [[ALAC]] and issue [https://roundup.mplayerhq.hu/roundup/ffmpeg/issue82 #82].

''Mentor: Justin Ruggles''

=== Snow Job ===
This task involves finishing work on the [[Snow]] video codec to bring it to 1.0 quality.
* Document the whole Snow algorithm
* Fix all Snow related bugs on roundup
* faster halfpel interpolation (issue183)
* Try a different transform like an lapped biorthogonal transform instead of the wavelet (this could be better or worse only trying can tell ...)
* anything in [http://svn.mplayerhq.hu/ffmpeg/trunk/doc/TODO?view=co doc/TODO] about Snow and [http://svn.mplayerhq.hu/ffmpeg/trunk/doc/snow.txt?view=co snow.txt/TODO]
* anything else which might improve Snow quality per bitrate
''(The idea here is that the goal would be, do as much as the time allows, though we should decide on some minimum as all above is clearly not doable within the time)

''Mentor: Michael Niedermayer''

=== x264 Improvements ===
This task involve various possible improvements to the [[x264]] video encoder. Full details can be found on [[X264_Summer_Of_Code_2008|x264's Summer of Code page]].

== 2nd Tier Project Proposals ==
All that separates these proposals from their 1st tier brethren is a mentor. If you are particularly passionate about one of these tasks, perhaps you should attach your name to it. ''(Email me if you want to discuss it or need access to the Wiki. --[[User:Multimedia Mike|Multimedia Mike]] 21:58, 1 March 2008 (EST))''

==== GUI for FFmpeg ====
Build a gui for the libs of FFmpeg. The main objective in this task is to extent the codecs and formats to support querying of features and good defaults. The actual GUI should just be a simple skeleton with support for encoding of multiple files. Most of the work will be done in the libs.

==== Port FFmpeg to Visual Studio ====
Create a full working port including inline assembly.

==== Optimize FFT routines ====
Port djbfft and rework the fft framework in FFmpeg. This task can include a fixedpoint port and SIMD optimizations.

==== GSM Decoder ====
* Specification + sample implementation: http://kbs.cs.tu-berlin.de/~jutta/toast.html
* Samples: http://samples.mplayerhq.hu/A-codecs/GSM/
Also see [[GSM]].

==== AMR-WB Decoder ====
* Specification: http://www.3gpp.org/ftp/Specs/html-info/26-series.htm
* Samples: http://samples.mplayerhq.hu/A-codecs/amr/
Also see [[AMR]].

==== AMR-NB Encoder ====
* Specification: http://www.3gpp.org/ftp/Specs/html-info/26-series.htm
* Samples: http://samples.mplayerhq.hu/A-codecs/amr/
Also see [[AMR]].

==== Speex Decoder ====
* Specification: http://speex.org/docs/
* Samples: http://samples.mplayerhq.hu/A-codecs/speex/
Also see [[Speex]].

=== WMV3 Encoder ===
* Clearly defined task
* Primary goal: Encode video sequences such that they can be decoded by a Windows Media player.

This could either be done by improving [[Interesting Patches#WMV3 encoder by Denis Fortin|this patch]] or by writing the encoder from scratch.

=== Better handling of audio in libavcodec ===
* Info: http://wiki.multimedia.cx/index.php?title=Ffmpeg_audio_api
* Loosely defined task

=== LGPL reimplementation of GPL sws_scale parts ===
* Loosely defined task
* Primary goal: LGPL licensed sws_scale
* Secondary goal: removal of lavc scaler

=== Freeform Proposal ===
If you think you have a good idea for a FFmpeg Summer of Code project, propose it on the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list]. We will discuss it from there.

== Qualification Tasks ==
Many students apply for the Google Summer of Code and wish to work on a sexy multimedia project such as FFmpeg. All students will claim to be hard workers but we need a method of determining which students have a higher probability for success. Thus, we developed the qualification system during the 2007 season and will be enforcing the same system this year. A student must successfully complete a qualification task in order to be considered for an FFmpeg SoC project. In doing so, a student demonstrates that they:

* are willing to commit some time during the Summer of Code application review period in order to prove themselves
* can code C satisfactorily and with the same general style expected of the FFmpeg codebase
* can wrap their head around the code base
* can interact with the FFmpeg development mailing list
* can accept feedback and revise the code until it is suitable for inclusion in the main code base

'''Frequent Objection #1:''' ''But I don't have time to do a qualification task!'' Then how do we know you will have time to work on your task during the summer? The qualification tasks are selected to be fairly trivial by FFmpeg standards and should not be too difficult for a prospective FFmpeg contributor. If they ''are'' too difficult, maybe FFmpeg is not the project for you. Also, be encouraged by the fact that the app review period comes after the application submission deadline; i.e., you can work on a qualification task ''after'' you submit an application for FFmpeg. But you will not be considered for an SoC project slot unless you have satisfactorily completed a qualification task.

'''Process:''' If you are interested in applying for FFmpeg's Summer of Code and, by extension, interested in working on a qualification task, the first step is to subscribe to the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel FFmpeg development mailing list] and indicate your interest and which project you plan to work on.

=== Finish up a previous incomplete SoC project ===

Several SoC projects from previous years have not yet made it into FFmpeg. Taking any of them and finishing them up to the point that they can be included should make for a good qualification task. Check out the [[FFmpeg Summer Of Code]] overview page and look for the unfinished projects, like AMR-NB, QCELP, Dirac, TS muxer, JPEG 2000.

* Bartlomiej Wolowiec is working on finishing the EAC3 decoder [http://lists.mplayerhq.hu/pipermail/ffmpeg-soc/2008-March/002745.html].

=== Generic Colorspace system ===
This task involves adding support more than 8 bits per component (Y on 10 bits, U on 10 bits, V on 10 bits for example)
and generic simple conversion to other colorspaces.

''Does this have to do with revising FFmpeg's infrastructure? If so, then it doesn't feel like a qualification task. If it's something simpler, then the vague description does not convey that simplicity. Please expound.'' --[[User:Multimedia Mike|Multimedia Mike]] 12:56, 25 February 2008 (EST)

''I don't think so, extending PixFmt to extended structure with finegrained description like depth, range values, colorspace, sample period, and write generic simple conversion from all formats to all others, like suggested by Michael on the mailing list. Conversion routine can be a good qualification task for video encoders/decoders. What do you think ?
--[[User:Bcoudurier|Baptiste Coudurier]] 00:30, 29 February 2008 (EST)

=== Cleanup of MLP decoder ===
This task involves adding a decoder to FFmpeg to play [[Meridian Lossless Packing|MLP]] audio data. The hard work has already been done; now a volunteer needs to take the existing decoder patch and make it satisfactory for inclusion into the codebase. MLP samples referenced from the [[Meridian Lossless Packing|MLP]] Wiki page.

Latest version of the MLP patch: http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-January/040234.html

And the comments: http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-January/040251.html

Claimed by: Andy Gocke

=== Support PB frame mode for H.263i ===
Details are in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue27

=== Patch cleanup for MPEG 1 & 2 optimizations ===
Details are in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue100

=== Implement a Vivo demuxer for FFmpeg ===
Implement an FFmpeg demuxer for the [[Vivo]] file format. The best reference for understanding the format would be MPlayer's [http://svn.mplayerhq.hu/mplayer/trunk/libmpdemux/demux_viv.c?view=markup existing .viv demuxer].

This task corresponds to issue 99: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue99

''I am ready to help out with understanding MPlayer's demuxer, esp. MPlayer API stuff if necessary.
--[[User:Reimar|Reimar]] 15:46, 1 March 2008 (EST)

* Marcondes Ricarte is working on this [http://lists.mplayerhq.hu/pipermail/ffmpeg-soc/2008-March/002704.html]

=== Optimal Huffman tables for (M)JPEG ===
This task is outlined at http://guru.multimedia.cx/small-tasks-for-ffmpeg/ and is tracked in the issue tracker: http://roundup.mplayerhq.hu/roundup/ffmpeg/issue267

* Deep Pal [http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-March/043547.html asked] this task to be assigned to him in the ffmpeg-devel mailing list.

=== RL2 Playback System ===
This task is to implement an FFmpeg playback subsystem for [[RL2]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[RL2|The RL2 page]] contains the specs necessary to complete this task and points to downloadable samples.

:''Sascha Sommer sent a [http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2008-March/043598.html patch] to implement this to ffmpeg-devel.''

=== YOP Playback System ===
This task is to implement an FFmpeg playback subsystem for [[Psygnosis YOP]] files. This will entail writing a new file demuxer and video decoder, both of which are trivial by FFmpeg standards. [[Psygnosis YOP|The Psygnosis YOP page]] contains the specs necessary to complete this task and points to downloadable samples.

* Claimed by Indrani

=== BFI Playback System ===
This task is to implement an FFmpeg playback subsystem for [[BFI]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[BFI|The BFI page]] contains the specs necessary to complete this task and points to downloadable samples.

=== M95 Playback System ===
This task is to implement an FFmpeg playback subsystem for [[M95]] files. This will entail writing a new file demuxer and video decoder (the audio is already uncompressed), both of which are trivial by FFmpeg standards. [[M95|The M95 page]] contains the specs necessary to complete this task and points to downloadable samples.

=== SSE2 iDCT Optimization ===
Incorporate an invert discrete cosine transform for SSE2-capable CPUs. The hardest work is already done-- dig up Intel's AP-945 application programming note which will spell out precisely how to do this. Mostly, this involves adapting the ASM code for gcc AT&T syntax.

:''I will be working on this.'' - [[User:Astrange|Alexander Strange]]

=== Apple RPZA encoder ===
Clean up the patch for svn inclusion. The current code can be found from here "[[Interesting Patches]]".

=== IFF demuxer ===
Implement demuxing of 8svx audio.

=== Interesting Patches ===
There is a growing backlog of "[[Interesting Patches]]" for FFmpeg tracked on this Wiki. Each one requires a volunteer to task the initiative to clean up the patch to the satisfaction of the project leaders so that it can finally be included.

=== Some bug on the bugtracker ===
From this page you can find the bugtracker: http://ffmpeg.mplayerhq.hu/bugreports.html
Some issues can qualify as a qualification task.

=== Legacy Tasks ===
Many tasks were suggested during the 2007 season. Any task that is not marked as '''completed''' is probably fair game, but ask on the list, just to be sure: http://wiki.multimedia.cx/index.php?title=FFmpeg_Summer_Of_Code_2007#Qualification_tasks

=== Freeform Tasks ===
If you have an idea for a simple task, come and discuss it on the [https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel development mailing list] and the devs might approve it.

[[Category:FFmpeg]]

X264 Summer Of Code 2008

2008-03-17T20:32:06Z

Dark Shikari:

''(Note: page copied with minor modifications from [http://wiki.videolan.org/SoC_x264 the Videolan wiki])''<br><br>
[[x264]] has loads of possibilities for [[FFmpeg Summer Of Code 2008]] projects. This is part of the FFmpeg Summer of Code 2008.

*Mentor (and author of this page): Dark Shikari
*Possible backup mentor: pengvado

==Introduction to x264==
x264 is probably the most efficient, compression-wise, open source video encoder there is. It is quite competitive with commercial encoders, outclassing a large number of them.

While not actually part of ffmpeg (it has its own codebase), it is a major library used by ffmpeg, licensed under the GPL, in addition to being a standalone encoder. As the only major open-source H.264 encoder, x264 has a near-complete monopoly on H.264 encoding in the consumer world, along with being used by many major corporations, including Facebook and Google. Some companies, such as Avail Media, have in the past offered bounties on improvements to the encoder.

==x264 project ideas==
This is not at all an exhaustive list; this is just a few I thought up with. I'm willing to mentor any reasonable project on x264 to the best of my ability. I'm being pretty conservative here, so I'm picking projects that are probably not at all too ambitious for a good student. If anything, I might be underestimating the amount of work that can be done, so feel free to propose something else if you're feeling creative.
:-- Dark Shikari

===Size key===
Depends heavily on the skill and willingness to work of the student. An extremely dedicated and talented student might be able to implement MBAFF in a summer, but it is certainly not fair to expect such a thing from most students.

*Very Large: Probably too large to completed in one summer.
*Large: Probably the right size for a full-summer project.
*Medium: Probably too small. Could be combined with another project, of course.
*Small: A small project, but definitely useful, and could be part of a larger project.

===Skills needed===
These are required for all listed projects and probably anything not listed, too.
*Basic C programming.
*Basic understanding of video encoding, or at least willingness to do the appropriate reading up on the topic before the summer begins.
*Confidence in the ability to learn the following and similar topics:
:*Discrete cosine transform and similar frequency transforms
:*Motion estimation and compensation
:*Quantization and entropy encoding

==Projects==
===Fast inter refinement===
''Size: Medium to large.''

Description: Improve heuristics and decision-making for inter refinement to improve efficiency on non-insane encoding settings. This would involve various early termination heuristics along with methods of deciding which partition modes need to be searched while performing minimal actual searching on those partition modes. This would be similar to, but a vastly more in-depth analysis of what was proposed in the "Fast-Ref-Search" patch.

Difficulty: Medium

===Fast intra refinement===
''Size: Small to medium''

Description: Similar to above, but covering intra modes instead. Would probably involve considerable statistical analysis of intra mode data, along with creative solutions for improved RDO refinement. We already have some ideas on this one, but haven't implemented any of them.

Difficulty: Medium

===RDO B-frame decision===
''Size: Medium to large''

Description: x264's biggest weakness is its B-frame decision algorithm, which can often be extremely subtopimal, with OPSNR losses as high as 1db in some cases. Improving this would drastically increase the effectiveness of the encoder.

Difficulty: Medium-high

===Other possible projects===
Anything here (and not here) can potentially be picked from at the request of a student.

*Assembly optimizations of any sort
:*Extra skills: Assembly coding
:*Difficulty: Medium
:*Examples:
::*Port cacheline split to the motion compensation code for increased speed (this could further be used to improve ffh264's decoding).
::*Assembly-optimize some things that haven't been already.
::*Port some MMX assembly to SSE where it seems useful.
::*Play around with potential SSE4 optimizations.

*Psychovisual optimizations for mode decision and quantization (e.g. QNS)
:*Extra skills: Creativity and perhaps some understanding of DCT/Fourier math.
:*Difficulty: Medium-high
:*Examples:
::*SSIM-QNS optimization?
::*Adaptive deadzone?
::*Adaptive lambda?

*Implementing MBAFF or PicAFF (potentially too difficult for a SoC project, however)
:*Difficulty: Very high

*Fast RD optimization using heuristics
:*Extra skills: Reading lots of IEEE papers
:*Difficulty: Medium

*Motion search improvements
:*Difficulty: Medium

*Anything else reasonable, honestly. There's all sorts of ideas floating around.

==Contact info==
If you are interested, drop by #ffmpeg-devel, #ffmpeg, #x264, or #x264dev on Freenode.

X264 Summer Of Code 2008

2008-03-17T20:31:15Z

Dark Shikari: new page

''(Note: page copied with minor modifications from [http://wiki.videolan.org/SoC_x264 the Videolan wiki])''
[[x264]] has loads of possibilities for [[FFmpeg Summer Of Code 2008]] projects. This is part of the FFmpeg Summer of Code 2008.

*Mentor (and author of this page): Dark Shikari
*Possible backup mentor: pengvado

==Introduction to x264==
x264 is probably the most efficient, compression-wise, open source video encoder there is. It is quite competitive with commercial encoders, outclassing a large number of them.

While not actually part of ffmpeg (it has its own codebase), it is a major library used by ffmpeg, licensed under the GPL, in addition to being a standalone encoder. As the only major open-source H.264 encoder, x264 has a near-complete monopoly on H.264 encoding in the consumer world, along with being used by many major corporations, including Facebook and Google. Some companies, such as Avail Media, have in the past offered bounties on improvements to the encoder.

==x264 project ideas==
This is not at all an exhaustive list; this is just a few I thought up with. I'm willing to mentor any reasonable project on x264 to the best of my ability. I'm being pretty conservative here, so I'm picking projects that are probably not at all too ambitious for a good student. If anything, I might be underestimating the amount of work that can be done, so feel free to propose something else if you're feeling creative.
:-- Dark Shikari

===Size key===
Depends heavily on the skill and willingness to work of the student. An extremely dedicated and talented student might be able to implement MBAFF in a summer, but it is certainly not fair to expect such a thing from most students.

*Very Large: Probably too large to completed in one summer.
*Large: Probably the right size for a full-summer project.
*Medium: Probably too small. Could be combined with another project, of course.
*Small: A small project, but definitely useful, and could be part of a larger project.

===Skills needed===
These are required for all listed projects and probably anything not listed, too.
*Basic C programming.
*Basic understanding of video encoding, or at least willingness to do the appropriate reading up on the topic before the summer begins.
*Confidence in the ability to learn the following and similar topics:
:*Discrete cosine transform and similar frequency transforms
:*Motion estimation and compensation
:*Quantization and entropy encoding

==Projects==
===Fast inter refinement===
''Size: Medium to large.''

Description: Improve heuristics and decision-making for inter refinement to improve efficiency on non-insane encoding settings. This would involve various early termination heuristics along with methods of deciding which partition modes need to be searched while performing minimal actual searching on those partition modes. This would be similar to, but a vastly more in-depth analysis of what was proposed in the "Fast-Ref-Search" patch.

Difficulty: Medium

===Fast intra refinement===
''Size: Small to medium''

Description: Similar to above, but covering intra modes instead. Would probably involve considerable statistical analysis of intra mode data, along with creative solutions for improved RDO refinement. We already have some ideas on this one, but haven't implemented any of them.

Difficulty: Medium

===RDO B-frame decision===
''Size: Medium to large''

Description: x264's biggest weakness is its B-frame decision algorithm, which can often be extremely subtopimal, with OPSNR losses as high as 1db in some cases. Improving this would drastically increase the effectiveness of the encoder.

Difficulty: Medium-high

===Other possible projects===
Anything here (and not here) can potentially be picked from at the request of a student.

*Assembly optimizations of any sort
:*Extra skills: Assembly coding
:*Difficulty: Medium
:*Examples:
::*Port cacheline split to the motion compensation code for increased speed (this could further be used to improve ffh264's decoding).
::*Assembly-optimize some things that haven't been already.
::*Port some MMX assembly to SSE where it seems useful.
::*Play around with potential SSE4 optimizations.

*Psychovisual optimizations for mode decision and quantization (e.g. QNS)
:*Extra skills: Creativity and perhaps some understanding of DCT/Fourier math.
:*Difficulty: Medium-high
:*Examples:
::*SSIM-QNS optimization?
::*Adaptive deadzone?
::*Adaptive lambda?

*Implementing MBAFF or PicAFF (potentially too difficult for a SoC project, however)
:*Difficulty: Very high

*Fast RD optimization using heuristics
:*Extra skills: Reading lots of IEEE papers
:*Difficulty: Medium

*Motion search improvements
:*Difficulty: Medium

*Anything else reasonable, honestly. There's all sorts of ideas floating around.

==Contact info==
If you are interested, drop by #ffmpeg-devel, #ffmpeg, #x264, or #x264dev on Freenode.