После конвертации некоторые файлы (~1%) ускоряются. Когда их открываешь в обычном плеере, то можно увидеть такую длительность воспроизведения: 1 секунда, 2 секунды, 4 секунды, 5 секунд, 7 секунд и т.д.
Конвертация происходит такой командой:
/usr/local/bin/ffmpeg -i fives_vid.mp4 -acodec libfaac -ab 128k -ac 2 -vcodec libx264 -vpre superfast -crf 24 -threads 0 -map_meta_data 0:0 -f flv fives_vid.flv
Исходник:
Свернутый текст
FFmpeg version SVN-r26402, Copyright © 2000-2011 the FFmpeg developers
built on Oct 23 2012 16:52:18 with gcc 4.4.6 20120305 (Red Hat 4.4.6-4)
configuration: --enable-gpl --enable-version3 --enable-nonfree --enable-postproc --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-x11grab
libavutil 50.36. 0 / 50.36. 0
libavcore 0.16. 1 / 0.16. 1
libavcodec 52.108. 0 / 52.108. 0
libavformat 52.93. 0 / 52.93. 0
libavdevice 52. 2. 3 / 52. 2. 3
libavfilter 1.74. 0 / 1.74. 0
libswscale 0.12. 0 / 0.12. 0
libpostproc 51. 2. 0 / 51. 2. 0
Seems stream 1 codec frame rate differs from container frame rate: 5994.00 (5994/1) -> 29.97 (2997/100)
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'fives_vid.mp4':
Metadata:
major_brand : mp42
minor_version : 1
compatible_brands: mp42avc1
creation_time : 2008-10-01 09:47:09
Duration: 00:04:27.28, start: 0.000000, bitrate: 816 kb/s
Stream #0.0(eng): Audio: aac, 44100 Hz, stereo, s16, 122 kb/s
Metadata:
creation_time : 2008-10-01 09:47:09
Stream #0.1(eng): Video: h264, yuv420p, 720x480, 690 kb/s, 29.96 fps, 29.97 tbr, 2997 tbn, 5994 tbc
Metadata:
creation_time : 2008-10-01 09:47:09
At least one output file must be specified
built on Oct 23 2012 16:52:18 with gcc 4.4.6 20120305 (Red Hat 4.4.6-4)
configuration: --enable-gpl --enable-version3 --enable-nonfree --enable-postproc --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-x11grab
libavutil 50.36. 0 / 50.36. 0
libavcore 0.16. 1 / 0.16. 1
libavcodec 52.108. 0 / 52.108. 0
libavformat 52.93. 0 / 52.93. 0
libavdevice 52. 2. 3 / 52. 2. 3
libavfilter 1.74. 0 / 1.74. 0
libswscale 0.12. 0 / 0.12. 0
libpostproc 51. 2. 0 / 51. 2. 0
Seems stream 1 codec frame rate differs from container frame rate: 5994.00 (5994/1) -> 29.97 (2997/100)
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'fives_vid.mp4':
Metadata:
major_brand : mp42
minor_version : 1
compatible_brands: mp42avc1
creation_time : 2008-10-01 09:47:09
Duration: 00:04:27.28, start: 0.000000, bitrate: 816 kb/s
Stream #0.0(eng): Audio: aac, 44100 Hz, stereo, s16, 122 kb/s
Metadata:
creation_time : 2008-10-01 09:47:09
Stream #0.1(eng): Video: h264, yuv420p, 720x480, 690 kb/s, 29.96 fps, 29.97 tbr, 2997 tbn, 5994 tbc
Metadata:
creation_time : 2008-10-01 09:47:09
At least one output file must be specified
Полученные файл:
Свернутый текст
FFmpeg version SVN-r26402, Copyright © 2000-2011 the FFmpeg developers
built on Oct 23 2012 16:52:18 with gcc 4.4.6 20120305 (Red Hat 4.4.6-4)
configuration: --enable-gpl --enable-version3 --enable-nonfree --enable-postproc --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-x11grab
libavutil 50.36. 0 / 50.36. 0
libavcore 0.16. 1 / 0.16. 1
libavcodec 52.108. 0 / 52.108. 0
libavformat 52.93. 0 / 52.93. 0
libavdevice 52. 2. 3 / 52. 2. 3
libavfilter 1.74. 0 / 1.74. 0
libswscale 0.12. 0 / 0.12. 0
libpostproc 51. 2. 0 / 51. 2. 0
[flv @ 0x2c1c510] Estimating duration from bitrate, this may be inaccurate
Seems stream 0 codec frame rate differs from container frame rate: 59.94 (2997/50) -> 30.00 (30/1)
Input #0, flv, from 'fives_vid.flv':
Metadata:
duration : 267
width : 720
height : 480
videodatarate : 195
framerate : 30
videocodecid : 7
audiodatarate : 125
audiosamplerate : 44100
audiosamplesize : 16
stereo : true
audiocodecid : 10
major_brand : mp42
minor_version : 1
compatible_brands: mp42avc1
creation_time : 2008-10-01 09:47:09
encoder : Lavf52.93.0
filesize : 11311307
Duration: 00:04:27.28, start: 0.066000, bitrate: 328 kb/s
Stream #0.0: Video: h264, yuv420p, 720x480, 200 kb/s, 30 tbr, 1k tbn, 59.94 tbc
Stream #0.1: Audio: aac, 44100 Hz, stereo, s16, 128 kb/s
At least one output file must be specified
built on Oct 23 2012 16:52:18 with gcc 4.4.6 20120305 (Red Hat 4.4.6-4)
configuration: --enable-gpl --enable-version3 --enable-nonfree --enable-postproc --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-x11grab
libavutil 50.36. 0 / 50.36. 0
libavcore 0.16. 1 / 0.16. 1
libavcodec 52.108. 0 / 52.108. 0
libavformat 52.93. 0 / 52.93. 0
libavdevice 52. 2. 3 / 52. 2. 3
libavfilter 1.74. 0 / 1.74. 0
libswscale 0.12. 0 / 0.12. 0
libpostproc 51. 2. 0 / 51. 2. 0
[flv @ 0x2c1c510] Estimating duration from bitrate, this may be inaccurate
Seems stream 0 codec frame rate differs from container frame rate: 59.94 (2997/50) -> 30.00 (30/1)
Input #0, flv, from 'fives_vid.flv':
Metadata:
duration : 267
width : 720
height : 480
videodatarate : 195
framerate : 30
videocodecid : 7
audiodatarate : 125
audiosamplerate : 44100
audiosamplesize : 16
stereo : true
audiocodecid : 10
major_brand : mp42
minor_version : 1
compatible_brands: mp42avc1
creation_time : 2008-10-01 09:47:09
encoder : Lavf52.93.0
filesize : 11311307
Duration: 00:04:27.28, start: 0.066000, bitrate: 328 kb/s
Stream #0.0: Video: h264, yuv420p, 720x480, 200 kb/s, 30 tbr, 1k tbn, 59.94 tbc
Stream #0.1: Audio: aac, 44100 Hz, stereo, s16, 128 kb/s
At least one output file must be specified
Метаданные генерирует flvmeta