使用FFMPEG转换Android视频

Question

我想要做的是将视频转换为将在Android中播放的mp4格式.

我已经浏览了http://developer.android.com/guide/appendix/media-formats.html

我正在设置以下选项

-vcodec libx264 -vprofile baseline -acodec libfaac -ar 44100 -ac 1 -ab 128k 

但我收到错误消息"抱歉,此视频无法流式传输到此设备"

我使用videoJS http://video-js.zencoder.com/oceans-clip.mp4在Android浏览器中播放视频,它运行正常.

我下载视频oceans-clip.mp4并尝试使用极简主义选项进行转换

-y -i working.mp4 -vprofile baseline pleasework.mp4

但我收到相同的错误消息.

以下是视频文件的FFMPEG信息转储

Working.mp4

Array
(
    [0] => ffmpeg version N-40229-g24e3f44-syslint Copyright (c) 2000-2012 the FFmpeg developers
    [1] =>   built on Apr 29 2012 22:01:41 with gcc 4.1.2 20080704 (Red Hat 4.1.2-52)
    [2] =>   configuration: --prefix=/usr/local/cpffmpeg --enable-shared --enable-nonfree --enable-gpl --enable-pthreads --enable-libopencore-amrnb --enable-decoder=liba52 --enable-libopencore-amrwb --enable-libfaac --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --extra-cflags=-I/usr/local/cpffmpeg/include/ --extra-ldflags=-L/usr/local/cpffmpeg/lib --enable-version3 --extra-version=syslint
    [3] =>   libavutil      51. 48.100 / 51. 48.100
    [4] =>   libavcodec     54. 17.101 / 54. 17.101
    [5] =>   libavformat    54.  3.100 / 54.  3.100
    [6] =>   libavdevice    53.  4.100 / 53.  4.100
    [7] =>   libavfilter     2. 72.100 /  2. 72.100
    [8] =>   libswscale      2.  1.100 /  2.  1.100
    [9] =>   libswresample   0. 11.100 /  0. 11.100
    [10] =>   libpostproc    52.  0.100 / 52.  0.100
    [11] => Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'working.mp4':
    [12] =>   Metadata:
    [13] =>     major_brand     : isom
    [14] =>     minor_version   : 1
    [15] =>     compatible_brands: isomavc1
    [16] =>     creation_time   : 2010-05-18 04:24:00
    [17] =>   Duration: 00:00:46.54, start: 0.000000, bitrate: 3342 kb/s
    [18] =>     Stream #0:0(und): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p, 640x264 [SAR 132:133 DAR 320:133], 3195 kb/s, SAR 127:128 DAR 635:264, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc
    [19] =>     Metadata:
    [20] =>       creation_time   : 2010-05-18 04:24:00
    [21] =>       handler_name    : GPAC ISO Video Handler
    [22] =>     Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, s16, 144 kb/s
    [23] =>     Metadata:
    [24] =>       creation_time   : 2010-05-18 04:24:01
    [25] =>       handler_name    : GPAC ISO Audio Handler
    [26] => At least one output file must be specified
)

不工作.mp4

Array
(
    [0] => ffmpeg version N-40229-g24e3f44-syslint Copyright (c) 2000-2012 the FFmpeg developers
    [1] =>   built on Apr 29 2012 22:01:41 with gcc 4.1.2 20080704 (Red Hat 4.1.2-52)
    [2] =>   configuration: --prefix=/usr/local/cpffmpeg --enable-shared --enable-nonfree --enable-gpl --enable-pthreads --enable-libopencore-amrnb --enable-decoder=liba52 --enable-libopencore-amrwb --enable-libfaac --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --extra-cflags=-I/usr/local/cpffmpeg/include/ --extra-ldflags=-L/usr/local/cpffmpeg/lib --enable-version3 --extra-version=syslint
    [3] =>   libavutil      51. 48.100 / 51. 48.100
    [4] =>   libavcodec     54. 17.101 / 54. 17.101
    [5] =>   libavformat    54.  3.100 / 54.  3.100
    [6] =>   libavdevice    53.  4.100 / 53.  4.100
    [7] =>   libavfilter     2. 72.100 /  2. 72.100
    [8] =>   libswscale      2.  1.100 /  2.  1.100
    [9] =>   libswresample   0. 11.100 /  0. 11.100
    [10] =>   libpostproc    52.  0.100 / 52.  0.100
    [11] => Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'pleasework.mp4':
    [12] =>   Metadata:
    [13] =>     major_brand     : isom
    [14] =>     minor_version   : 512
    [15] =>     compatible_brands: isomiso2avc1mp41
    [16] =>     creation_time   : 2010-05-18 04:24:00
    [17] =>     encoder         : Lavf54.3.100
    [18] =>   Duration: 00:00:46.54, start: 0.000000, bitrate: 1843 kb/s
    [19] =>     Stream #0:0(und): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p, 640x264 [SAR 127:128 DAR 635:264], 1715 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc
    [20] =>     Metadata:
    [21] =>       creation_time   : 2010-05-18 04:24:00
    [22] =>       handler_name    : VideoHandler
    [23] =>     Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, s16, 124 kb/s
    [24] =>     Metadata:
    [25] =>       creation_time   : 2010-05-18 04:24:00
    [26] =>       handler_name    : SoundHandler
    [27] => At least one output file must be specified
)

元数据看起来几乎相同但它似乎没有在Android中播放.任何帮助赞赏.

Answer 1

由ffmpeg创建的MP4尾部有moov头.这就是您收到此错误消息的原因.ffmpeg可以将moov标头放在前面(适合流式传输).

简单地运行:

ffmpeg -i <input> -c:v libx264 -c:a aac -movflags +faststart output.mp4

另请参阅ffmpeg中的后处理以在MP4文件中移动'moov atom'(qt-faststart)

Answer 2

不再支持libfaac,您可以使用此配置:

ffmpeg -i <input> -s 480x320 -vcodec mpeg4 -acodec aac -strict -2 -ac 1 -ar 16000 -r 13 -ab 32000 -aspect 3:2 <output>