VideoReDo TV Suite is supposed to have the ability to edit 4K HEVC. if your MKV file contains Dolby TrueHD with Atmos object data then it won't be lossless because the Atmos object data won't be preserved. The conversion to 8-channel LPCM should be lossless if your MKV file contains Dolby TrueHD without Atmos object data. Since Dolby tightly restricts access to their TrueHD encoders and to information about their TrueHD format, software capable of cutting and joining TrueHD audio and exporting it as TrueHD audio probably doesn't exist, particularly software that consumers can obtain. I'm familiar with these tools, but maybe you can help me find the solution. So how can I edit this MKV losslessly? I'm open to paid software or using multiple tools, command line, ffmpeg, avisynth, etc.

And I don't know enough about audio to know if VideoReDo's PCM output is the same as the original Dolby TrueHD track. My only solution so far is to edit the video in TMPGEnc and edit the audio in VideoReDo, then mux the tracks together with MKVToolNix. I want a solution for losslessly editing this file and only re-encoding the cut areas.

It saves the audio as an 8-channel PCM track. The only software I have found to edit the Dolby TrueHD 7.1 audio is VideoReDo TVSuite 6. The only software I have found to edit the 4K UHD HEVC video is TMPGEnc MPEG Smart Renderer 6. I want to edit it and 'smart render' it back to MKV. I have a Blu-ray with 4K UHD HEVC video and Dolby TrueHD 7.1 audio ripped to MKV with MakeMKV.

Makemkv 4k bluray