Difference between revisions of "AMV"

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* Extension: amv
 
* Extension: amv
* Samples: [http://www.mympxplayer.org/sample-videos-dc7.html] and [http://samples.mplayerhq.hu/amv/]
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* Samples:  
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** http://www.mympxplayer.org/sample-videos-dc7.html
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** http://samples.mplayerhq.hu/amv/
  
 
==AMV video origin and history==
 
==AMV video origin and history==
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==AMV Video File Format==
 
==AMV Video File Format==
AMV files are a variant of AVI with the strings "AVI" and "avih" in the header replaced with "AMV" and "amvh". The avi header contains several 'garbage' values as many of the parameters are hardcoded. It contains a [[RIFF]] packed stream of video ([[Talk:AMV|video codec?]]) and [[MP3]] encoded audio.  
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AMV files are a variant of AVI with the strings "AVI" and "avih" in the header replaced with "AMV" and "amvh". The avi header contains several 'garbage' values as many of the parameters are hardcoded. It contains a [[RIFF]] packed stream of video and audio.  
  
There is a open source decoder (written in Perl) for the format at [http://svn.rot13.org/index.cgi/amv]. According to its author [http://blog.rot13.org/2007/08/amv_free_decoder_works.html], the video codec is a modified version of [[Motion JPEG]] but missing quantization tables which are fixed (from jpeg standard) and audio is a variant of [[IMA ADPCM]] where the first 8 bytes of each frame are:
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The video codec is a version of [[Motion JPEG]] with fixed quantization tables (taken from jpeg standard). Audio is a variant of [[IMA ADPCM]] where the first 8 bytes of each frame are:
 
* origin (16bits)
 
* origin (16bits)
 
* index (16bits)
 
* index (16bits)
 
* audio frame length (32bits).
 
* audio frame length (32bits).
The decoder extracts each frame into a [[JPEG]] file and then uses ffmpeg to encode the video in another format.
 
  
 
==AMV and MTV encoding/transcoding information and utilities==
 
==AMV and MTV encoding/transcoding information and utilities==
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* [http://code.google.com/p/amv-codec-tools/ amv-codec-tools] (GPLv2)
 
* [http://svn.rot13.org/index.cgi/amv open source decoder]
 
* [http://svn.rot13.org/index.cgi/amv open source decoder]
* [http://www.s1mp3.org/wiki/index.php/Video_encoding AMV encoding tips]
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* [http://wiki.s1mp3.org/Video_encoding AMV encoding tips]
 
* [http://www.mympxplayer.org/tools-dc10.html www.mympxplayer.org - MP4 resource site and support forum, with MTV conversion/transcoding tools and utilies, (plus sample downloads)]
 
* [http://www.mympxplayer.org/tools-dc10.html www.mympxplayer.org - MP4 resource site and support forum, with MTV conversion/transcoding tools and utilies, (plus sample downloads)]
 
==Software players that support AMV and MTV playback==
 
*Unknown
 
 
==Hardware players that support AMV and MTV playback==
 
[http://en.wikipedia.org/wiki/Chinese_MP4/MTV_Player '''Chinese-made portable MP3 players'''], also known as [http://en.wikipedia.org/wiki/S1_MP3_Player S1 MP3 Players].
 
  
 
==External Links==
 
==External Links==
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[[Category:Container Formats]]
 
[[Category:Container Formats]]
 
[[Category:Video Codecs]]
 
[[Category:Video Codecs]]
[[Category:Formats missing in FFmpeg]]
 

Latest revision as of 16:00, 25 January 2009

AMV video origin and history

Little is known about the history of the AMV file format other than it is used by Chinese-made portable MP3 players and has supposedly been created to allow video playback capabilities on inexpensive and low end equipment without increasing the cost of those players with the license royalties and more processor power needed for other more complex format/codec pairs.

AMV Video File Format

AMV files are a variant of AVI with the strings "AVI" and "avih" in the header replaced with "AMV" and "amvh". The avi header contains several 'garbage' values as many of the parameters are hardcoded. It contains a RIFF packed stream of video and audio.

The video codec is a version of Motion JPEG with fixed quantization tables (taken from jpeg standard). Audio is a variant of IMA ADPCM where the first 8 bytes of each frame are:

  • origin (16bits)
  • index (16bits)
  • audio frame length (32bits).

AMV and MTV encoding/transcoding information and utilities

External Links