ffmpeg -ss 0 -t 30 -f lavfi -i color=c=0x0000ff:s=1280x720:r=25 -vcodec libx264 -r:v 25 0000ff_30s_1280x720.mp4
同时添加一条音频track
ffmpeg -ss 0 -t 30 -f lavfi -i color=c=0x0000ff:s=1280x720:r=25 -ss 0 -t 30 -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=48000 -vcodec libx264 -r:v 25 -c:a aac 0000ff_30s_1280x720_aac.mp4
同时添加两条不同格式音频track
ffmpeg -ss 0 -t 30 -f lavfi -i color=c=0x0000ff:s=1280x720:r=25 -ss 0 -t 30 -f lavfi -i anullsrc=channel_layout=5.1:sample_rate=48000 -ss 0 -t 30 -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=48000 -map 0:v -map 1:a -map 2:a -c:v libx264 -r:v 25 -c:a:0 ac3 -c:a:1 aac 0ff0ff_30s_1280x720_aac2_ac35.1.mp4