I think we can add some clarification --- HDV on a Blu-ray Disc Without Re-encoding An MTS file is a video file saved in the high-definition (HD) MPEG Transport Stream video format, commonly called AVCHD. It contains HD video compatible with Blu-ray disc format and is based on the MPEG-2 transport stream. MTS files are often used by Sony, Panasonic, Canon and other HD camcorders. Legal input for Video – MPEG1VIDEO, MPEG2VIDEO, H264; Audio – MP1, MP2, AC3, AC3PLUS, DTS, TRUHD. Note, mp2 and mp1 audio codecs are valid for transport stream itself but not as on-disk format for Blu-Rays. In this case you still can save original video by using ffmpeg's switches -c:v copy -c:a ac3 , while outputting into another temporal ts container. {waiting for Terje's results on pcm_bluray case} --- I think all m2ts files you used for testing were h264/aac (or ac3), not from-camcoder HDVs with mpeg2 video/mp2 audio. you can try HDV-in-mov from this folder as ffmpeg test file, I think http://samples.mplayerhq.hu/mov/FCP/ ---- For creating a blu-ray disc, if you have HDV MPEG-2 media that is in blu-ray format, you can save the original quality of your work, rather than rendering it to another format. {I hope Terje will let us know if bdwrite still works with bluray pcm audio as produced by ffmpeg 5.1+}