Small FFmpeg Tasks
This page contains ideas for small, relatively simple tasks for the FFmpeg project. People who might be interested in trying one of these tasks:
- Someone who wants to contribute to FFmpeg and needs to find a well-defined task to start with
- Someone who wishes to qualify for one of FFmpeg's coveted Summer of Code project slots
- An existing FFmpeg developer who has been away from the project for a while and needs a smaller task as motivation for re-learning the codebase
For other tasks of varying difficulty, see the Interesting Patches page.
If you would like to work on one of these tasks, please take these steps:
- Subscribe to the FFmpeg development mailing list and indicate your interest
- Ask Multimedia Mike for a Wiki account so you can claim your task on this Wiki
If you would like to add to this list, please be prepared to explain some useful details about the task. Excessively vague tasks with no supporting details will be ruthlessly deleted.
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 Dirac, TS muxer, JPEG 2000.
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. --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 ? --Baptiste Coudurier 00:30, 29 February 2008 (EST)
Make the SoC dts encoder multichannel capable
Here is a skeleton for a dts encoder http://svn.mplayerhq.hu/soc/dcaenc/, currently it can only encode stereo streams. The task is to extend it to support 5.1 channels also.
Specs and info can be found here: http://wiki.multimedia.cx/index.php?title=DTS
Extend GIF Encoder and Decoder to support Animated GIFs
reverse engineer realplayer's ivr format and create a demuxer for it
samples on IVR page.
Implement a Vivo demuxer for FFmpeg
This task corresponds to issue 99: http://roundup.ffmpeg.org/roundup/ffmpeg/issue99
I am ready to help out with understanding MPlayer's demuxer, esp. MPlayer API stuff if necessary. --Reimar 15:46, 1 March 2008 (EST)
Port missing demuxers from MPlayer to FFmpeg
MPlayer supports a few container formats in libmpdemux that are not yet present in libavformat. Porting them over and gettting them relicensed as LGPL or reimplementing them from scratch should make reasonable small tasks.
- TiVo -- Jai Menon is working on this
- VIVO -- Daniel Verkamp has a patch for this
- SL support for MPEG-TS (anyone got samples?)
Optimal Huffman tables for (M)JPEG
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. The M95 page contains the specs necessary to complete this task and points to downloadable samples.
BRP Playback System
This task is to implement an FFmpeg playback subsystem for BRP files. This will entail writing a new file demuxer as well as a video decoder that can handle at least 2 variations of format data. Further, write an audio decoder for the custom DPCM format in the file. All of these tasks are considered trivial by FFmpeg standards. The BRP page contains the specs necessary to complete this task and points to downloadable samples for both known variations.
16-bit VQA Video Decoder
FFmpeg already supports Westwood VQA files. However, there are 3 variations of its custom video codec. The first 2 are supported in FFmpeg. This task involves implementing support for the 3rd variation. Visit the VQA samples repository: http://samples.mplayerhq.hu/game-formats/vqa/ -- The files in the directories Tiberian Sun VQAs/, bladerunner/, and dune2000/ use the 3rd variation of this codec. The VQA page should link to all the details you need to support this format.
HNM4 Playback System
This task is to implement an FFmpeg playback subsystem for HNM4 variant of the HNM format. This will entail writing a new file demuxer and video decoder, both of which are trivial by FFmpeg standards. The HNM4 page contains the specs necessary to complete this task and links to downloadable samples.
Apple RPZA encoder
A patch was once sent to the ffmpeg-devel mailing list to include an encoder for the Apple RPZA video codec. That code can be found on the "Interesting Patches" page. This qualification task involves applying that patch so that it can compile with current FFmpeg SVN code and then cleaning it up per the standards of the project. Engage the mailing list to learn more about what to do.
QuickTime Edit List Support
Implement edit list support in FFmpeg's QuickTime demuxer (libavformat/mov.c). This involves parsing the 'elst' atom in a QuickTime file. For a demonstration of how this is a problem, download the file menace00.mov from http://samples.mplayerhq.hu/mov/editlist/ and play it with ffplay or transcode it with ffmpeg. Notice that the audio and video are ever so slightly out of sync. Proper edit list support will solve that. Other samples in that directory also presumably exhibit edit list-related bugs. The Xine demuxer has support for this, it might be useful for hints.
(patch was submitted to ffmpeg-devel , around 14 March 2009)
Implement the Flash Screen Video codec version 2
FFmpeg is missing both a decoder and an encoder. Would be nice to have that.
- Daniel Verkamp is working on this
Add wma fixed point decoder back into libavcodec
http://svn.rockbox.org/viewvc.cgi/trunk/apps/codecs/libwma/ Rockbox's fixed-point WMA decoder was adapted from the decoder in libavcodec.
VC1 timestamps in m2ts
Codec copy of VC1 from m2ts currently doesn't work. Either extend the VC1 parser to output/fix timestamps, or fix the timestamps from m2ts demuxing.
Revise the Flic Video decoder at libavcodec/flicvideo.c to support video transported in AVI or MOV files while making sure that data coming from the usual FLI files still works. 'AFLC' and 'flic' FourCC samples are linked from the Flic Video page.
Extend FFmpeg's MJPEG decoder to handle the different frames/packing of CJPG. Samples at: http://roundup.ffmpeg.org/roundup/ffmpeg/issue777
flip flag for upside-down codecs
about the flip, a patch that decodes images fliped when codec_tag == ff_get_fourcc("GEOX") is welcome. its a metter of 2lines manipulating data/linesize of imgages after get_buffer() or something similar [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
lavf-based concatenation tool
Unless we have multiple files input in FFmpeg, it would be nice to have some libavformat-based tool that would extract frames from multiple files (possible different containers as well) and put them into single one.
cljr and vcr1 encoders
According to this: http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/2009-February/063555.html both of the encoders are disabled, and won't compile if enabled. Michael would prefer to keep them around, and have someone grow them into full encoders.
implement some colorspace fourcc/codecs
some colorspace formats were uploaded to http://samples.mplayerhq.hu/V-codecs/ including:
CYUV.AVI is 8 Bit Interleaved 4:2:2 a12v.avi is 4:2:2:4 10 Bit Interleaved auv2.avi is 4:2:2:4 8 Bit Interleaved and V-codecs/yuv8/MAILTEST.AVI .
it might decode with current pixfmts, for that all you will need is:
cd ffmpeg svn di -r20378:20379
step by step tutorial for adding new input formats to swscale:
cd mplayer/libswscale/ svn di -r20426:20427 the hunks 3 and 5 you dont need, they are optional special converters also the change to isSupportedOut() you dont need above will add a new input format
another example for adding an input format
cd mplayer/libswscale/ svn di -r20604:20605
Implement Phantom Cine demuxer and Bayer format support for swscale
The format is described here: http://wiki.multimedia.cx/index.php?title=Phantom_Cine It will need support for Bayer -> RGB conversion in swscale to make the demuxer useful though.
support for YCoCg/RGB colorspace in FFV1
This would add a free lossless intra-frame RGB codec for all by FFmpeg supported platforms (most important MacOS + Windows) which is often asked for video editing in video forums (e.g. slashcam.de)
Metal Gear Solid Video format demuxer
Write a demuxer to play video files harvested from the game Metal Gear Solid: The Twin Snakes. The format is described on the wiki page Metal Gear Solid VP3 (which also contains links to samples). This page is based on observations and conjecture, so remember to engage the ffmpeg-devel mailing list with questions.
IFF ANIM decoder
Modify libavformat/iff.c to handle this chunk and write a decoder for the format. The wiki page at IFF ANIM has links to more information and source code. Samples can be found at http://www-user.tu-chemnitz.de/~womar/projects/iffanim/iffanim_samplepack.zip .
Write a decoder for this format using the information in the CDXL wiki page Discussed for the 2009 SoC
port missing decoders/demuxers from other open source projects.
Paris Audio File PAF IRCAM SF GNU Octave 2.0 MAT4 GNU Octave 2.1 MAT5 Portable Voice Format PVFSound Designer II SD2
samples are here: http://www.mega-nerd.com/tmp/SoundFileCollection-20050711-0902.tgz
HVDI_VOICE_DATA- packet GSM LPC CELP LPC10
many image formats not in ffmpeg yet.
MPEG-4 BIFS 3GPP DIMS LASeR SAF SVG SMIL VRML X3D XMT
many OPL2/OPL3 audio formats not in ffmpeg yet.
many music pattern formats not in ffmpeg yet.
AY GBS GYM HES KSS NSF, NSFE SAP SNES-SPC700 Sound Format VGM, VGZ
port Ut Video decoder/encoder
gpl v2 decoder/encoder at wiki page
Sony psp demuxer
create/port a demuxer for the sony playstation portable format PMP.
- Samples: http://samples.mplayerhq.hu/playstation/psp/
- mplayer demuxer: http://mplayer-ww.svn.sourceforge.net/viewvc/mplayer-ww/trunk/mplayer/libmpdemux/demux_pmp.c
libswscale PAL8 output
See the thread: "[RFC] libswscale palette output implementation": http://thread.gmane.org/gmane.comp.video.ffmpeg.devel/101397
vloopback output support
vloopback is a linux kernel device which allows to create a virtual video device where programs can write, and can be accessed as a normal video device: http://www.lavrsen.dk/twiki/bin/view/Motion/VideoFourLinuxLoopbackDevice
This would allow to write the ffmpeg output to a vloopdevice and be displayed by some a program reading from such device (e.g. skype, a voip client etc.).
An example of a program which uses vloopback: http://www.ws4gl.org/
Port video filters from MPlayer/VLC/Mjpegtools/Effectv/etc etc to libavfilter
There are plenty programs providing their own filters, many of them may be easily ported to the superior ;-) framework of libavfilter. Also may be possible to create wrappers around other libraries (e.g. opencv, libgimp, libshowphoto, libaa).
Add weighted motion compensation for B-frames in RV3/4
RealVideo 3 and 4 uses weighted motion compensation for B-frames (like H.264) but current code always uses simple averaging. Reverse-engineer weighted MC functions for B-frames and make RV3/4 decoder use them.
rar/zip/gz/bz2 etc demuxer
there are still compressed files out there (zipped raw wav, multi-rar'ed videos etc). create a decompression demuxer for them.
Less common AAC decoder features
Add support to the AAC decoder for object type AAC LTP, ER AAC LC, or AAC LC 960.