Converting a MKV file with DTS MA audio to AC3 5.1 (With no loss in video)

Question

I have a linux server on which i need to do this. I have a video MKV video file with AVC video and DTS MA audio, i need to convert this to a file with AC3 5.1 Audio with no loss in video and as little a loss as possible in audio. I've tried using ffmpeg tool, but cant seem to get the settings right. Any ideas?

Answer 1

Should be pretty simple actually. ffmpeg -i inputfile.mkv -c:v copy -c:a ac3 outputfile.mkv

This will copy the video track lossless and convert the audio track to ac3 while combining into a new .mkv file. This is assuming the DTS audio track is also multichannel 5.1. I believe it will auto merge the side channels into 5.1, if the source DTS is 7.1.