ffmpeg 遇见错误

错误：Too many packets buffered for output stream 0:1.

解决：添加命令 -max_muxing_queue_size 1024

错误："at least 3 arguments were expected, only 1 given in string"

解决: https://unix.stackexchange.com/questions/36310/strange-errors-when-using-ffmpeg-in-a-loop
在ffmpeg之前添加 </dev/null ，如
</dev/null ffmpeg -i %s.mp4 -f image2 %s.bmp