Will FFMPEG try to transcode to same encoding?-CodePudding

I would like to use ffmpeg transcoding for huge amount of video files from diverse set of codecs to one codec. There is chance that the video is video already is in wanted codec.

Will ffmpeg skip it or will actually try to transcode it (resulting probably in loss of quality) ?

Thank you for your answers

CodePudding user response：

ffmpeg will decode/encode the video, even if it was already encoded with the same parameters:

ffmpeg -i file.avi file0.mkv
ffmpeg -i file0.mkv file1.mkv
ffmpeg -i file1.mkv file2.mkv

ls -l file.avi file[012].mkv

-rw-rw-r-- 1 user group   742478 Nov 29 00:16 file.avi
-rw-rw-r-- 1 user group   228535 Nov 29 00:18 file0.mkv
-rw-rw-r-- 1 user group   219141 Nov 29 00:18 file1.mkv
-rw-rw-r-- 1 user group   211708 Nov 29 00:20 file2.mkv

As you can see, the sizes of MKV files are decreasing with each re-encoding. It means that there is a loss in quality.