Encoding 如何减少H.264电影中moov atom的大小，以改善智能手机的流媒体启动？
我们在智能手机（iOS和Android）上运行视频流服务。 我们使用H.264+AAC编码并使用mp4容器。 我们有一个问题，长电影（60分钟以上）需要很长时间才能完成 开始玩吧，并追踪到大尺寸的moov 这些电影的原子。 对于110分钟的电影来说，原子大到4.2Mb，这显然需要很长的时间 是时候通过3G下载到智能手机上了 有没有办法使moov原子变小？我们可以减少一点 降低音频采样率，但明显低于22kHz 这是不可接受的 我们使用ffmpeg作为编码器，使用MP4Box移动元数据 放在文件的前面。有什么办法让它成功吗 小一点的moov？有没有其他的编码器能制造出更小的moov 例如 大尺寸（280 Mb，1小时49分钟）可流化mp4（h.264，AAC）文件的头文件大小较大（4.2 Mb）。文件由两次传递ffmpeg和MP4Box编码，用于将元数据替换到文件的开头：Encoding 如何减少H.264电影中moov atom的大小，以改善智能手机的流媒体启动？,encoding,ffmpeg,h.264,mp4,aac,Encoding,Ffmpeg,H.264,Mp4,Aac,我们在智能手机（iOS和Android）上运行视频流服务。 我们使用H.264+AAC编码并使用mp4容器。 我们有一个问题，长电影（60分钟以上）需要很长时间才能完成 开始玩吧，并追踪到大尺寸的moov 这些电影的原子。 对于110分钟的电影来说，原子大到4.2Mb，这显然需要很长的时间 是时候通过3G下载到智能手机上了 有没有办法使moov原子变小？我们可以减少一点 降低音频采样率，但明显低于22kHz 这是不可接受的 我们使用ffmpeg作为编码器，使用MP4Box移动元数据 放在文件的前
/usr/bin/ffmpeg -i /var/lib/encoder/incoming/2388 -aspect 320:210 -threads 8 -vcodec libx264 -profile baseline -level 13 -flags +loop+mv4 -cmp 256 -partitions +parti4x4+parti8x8+partp4x4+partp8x8+partb8x8 -me_method hex -subq 7 -trellis 1 -refs 5 -bf 0 -me_range 16 -g 250 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71 -qmin 10 -qmax 51 -qdiff 4 -b:v 270k -maxrate 270k -bufsize 270k -g 30 -passlogfile /tmp/mediaservice/3100/video-IPH.ffmpeg -an -f rawvideo -pass 1 -y /dev/null
/usr/bin/ffmpeg -i /var/lib/encoder/incoming/2388 -aspect 320:210 -threads 8 -vcodec libx264 -profile baseline -level 13 -flags +loop+mv4 -cmp 256 -partitions +parti4x4+parti8x8+partp4x4+partp8x8+partb8x8 -me_method hex -subq 7 -trellis 1 -refs 5 -bf 0 -me_range 16 -g 250 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71 -qmin 10 -qmax 51 -qdiff 4 -b:v 270k -maxrate 270k -bufsize 270k -g 30 -passlogfile /tmp/mediaservice/3100/video-IPH.ffmpeg -acodec libfaac -ac 2 -b:a 32k -ar 44100 -f mp4 -pass 2 -y /var/lib/encoder/encoded/3100/video-IPH.mp4
/usr/bin/MP4Box -quiet -tmp /tmp/mediaservice/3100/ -inter 500 /var/lib/encoder/encoded/3100/video-IPH.mp4
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Tagged date : UTC 2012-09-25 07:21:37
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Tagged date : UTC 2012-09-25 07:21:37
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看起来AAC编码器或ffmpeg对AAC流的编码做得不好。采样率不是这里的问题。您是否尝试过使用其他AAC编码器
-acodec aac -strict experimental
我建议您不要先使用ffmpeg，然后再使用mp4box，而是看看ffmpeg的一个分支，名为。这可以在转码时将头放在起始位置，而不是作为后期处理。但考虑到它是ffmpeg分支，我不确定它是否会对您的头大小问题有所帮助。值得一试。我重新编码了电影
ffmpeg-I 1348645218_970458_2465.iph.mp4-acodec aac-strict experimental-vcodec copy 1348645218_970458_2465.iph.aac_exp.mp4-faststartqt faststart