{"id":2575,"date":"2010-06-23T21:55:20","date_gmt":"2010-06-24T04:55:20","guid":{"rendered":"http:\/\/multimedia.cx\/eggs\/?p=2575"},"modified":"2010-06-23T21:57:44","modified_gmt":"2010-06-24T04:57:44","slug":"ffmpeg-has-a-native-vp8-decoder","status":"publish","type":"post","link":"https:\/\/multimedia.cx\/eggs\/ffmpeg-has-a-native-vp8-decoder\/","title":{"rendered":"FFmpeg Has A Native VP8 Decoder"},"content":{"rendered":"

Thanks to David Conrad and Ronald Bultje<\/a> who committed their native VP8 video decoder to the FFmpeg codebase yesterday. At this point, it can decode 14\/17 of the VP8 test vectors that Google released during the initial open sourcing event. Work is ongoing on those 3 non-passing samples (missing bilinear filter). Meanwhile, FFmpeg’s optimization-obsessive personalities are hard at work optimizing the native decoder. The current decoder is already profiled to be faster than Google\/On2’s official libvpx.<\/p>\n

Testing<\/strong>
\nSo it falls to FATE<\/a> to test this on the ridiculous diversity of platforms that FFmpeg supports. I staged individual test specs for each of the 17 test vectors: vp8-test-vector-001<\/a> … vp8-test-vector-017<\/a>. After the samples<\/a> have propagated through to the various FATE installations, I’ll activate the 14 test specs that are currently passing.<\/p>\n

Initial Testing Methodology<\/strong>
\nInspired by Ronald Bultje’s idea<\/a>, I built the latest FFmpeg-SVN with libvpx enabled. Then I selected between the reference and native decoders as such:<\/p>\n

\r\n$<\/strong> for i in 001 002 003 004 005 006 007 008 009 \\\r\n 010 011 012 013 014 015 016 017\r\ndo\r\n  echo vp80-00-comprehensive-${i}.ivf\r\n  ffmpeg -vcodec libvpx -i \\\r\n    \/path\/to\/vp8-test-vectors-r1\/vp80-00-comprehensive-${i}.ivf \\\r\n    -f framemd5 - 2> \/dev\/null\r\ndone > refs.txt\r\n\r\n$<\/strong> for i in 001 002 003 004 005 006 007 008 009 \\\r\n 010 011 012 013 014 015 016 017\r\ndo\r\n  echo vp80-00-comprehensive-${i}.ivf\r\n  ffmpeg -vcodec vp8 -i \\\r\n    \/path\/to\/vp8-test-vectors-r1\/vp80-00-comprehensive-${i}.ivf \\\r\n    -f framemd5 - 2> \/dev\/null\r\ndone > native.txt\r\n\r\n$<\/strong> diff -u refs.txt native.txt\r\n<\/pre>\n
That reveals precisely which files differ.<\/p>\n","protected":false},"excerpt":{"rendered":"
FFmpeg (the ubiquitous multimedia backend library) handles VP8 decoding without any outside help<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[219],"tags":[],"class_list":["post-2575","post","type-post","status-publish","format-standard","hentry","category-vp8"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t