尝试使用ffmpeg，两次传递和-crf 50转换mp4，似乎对视频质量没有影响。总是很穷。
'/usr/bin/ffmpeg' '-y' '-i' '/app/storage/7/02/f47a2133-d0fe-6e7f-5e76-3efd22a88027_original.mp4' '-threads' '12' '-vcodec' 'libx264' '-acodec' 'libfaac' '-b:v' '1000k' '-refs' '6' '-coder' '1' '-sc_threshold' '40' '-flags' '+loop' '-me_range' '16' '-subq' '7' '-i_qfactor' '0.71' '-qcomp' '0.6' '-qdiff' '4' '-trellis' '1' '-b:a' '128k' '-pix_fmt' 'yuv420p' '-crf' '50' '-profile' 'baseline' '-movflags' '+faststart' '-vf' '[in]scale=trunc(iw/2)*2:trunc(ih/2)*2[out]' '-pass' '1' '-passlogfile' '/tmp/ffmpeg-passes5cde7ed5d2937fzaaz/pass-5cde7ed5d2caf' '/app/storage/7/02/f47a2133-d0fe-6e7f-5e76-3efd22a88027_temp.mp4'
'/usr/bin/ffmpeg' '-y' '-i' '/app/storage/7/02/f47a2133-d0fe-6e7f-5e76-3efd22a88027_original.mp4' '-threads' '12' '-vcodec' 'libx264' '-acodec' 'libfaac' '-b:v' '1000k' '-refs' '6' '-coder' '1' '-sc_threshold' '40' '-flags' '+loop' '-me_range' '16' '-subq' '7' '-i_qfactor' '0.71' '-qcomp' '0.6' '-qdiff' '4' '-trellis' '1' '-b:a' '128k' '-pix_fmt' 'yuv420p' '-crf' '50' '-profile' 'baseline' '-movflags' '+faststart' '-vf' '[in]scale=trunc(iw/2)*2:trunc(ih/2)*2[out]' '-pass' '2' '-passlogfile' '/tmp/ffmpeg-passes5cde7ed5d2937fzaaz/pass-5cde7ed5d2caf' '/app/storage/7/02/f47a2133-d0fe-6e7f-5e76-3efd22a88027_temp.mp4'
原文：https://giant.gfycat.com/CreepyZigzagFish.mp4
已转换：https://leonardo.osnova.io/f47a2133-d0fe-6e7f-5e76-3efd22a88027/-/format/mp4/
如何确定视频质量？我试图更改crf值，但似乎没关系。