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Lossless Codecs for Mac?

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Hello there  :cool:
I hope this finds you all well.

I am working on a fanedit on my Mac system, and have successfully done the following
--> Made an MKV file
--> Demuxed it, creating the following
       I. H.264 Video file
      II. Various Audio Tracks (5.1, Stereo, etc)
     III. Various subtitle tracks
--> Editing audio using Davinci Resolve 16
Obviously, Davinci Resolve cannot import and edit H.264 files, despite its ability to output them.

My question is really two questions:
--> Is there a codec conversion software that is lossless for Macs? I'm aware of ffmpeg, but I was under the impression there was some loss
--> In converting to an editable codec, is it best to use the original MKV or use the H.264 file?

Thank you for taking the time to read this,
All responses are welcome and appreciated!


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On a mac you'll want to go for the ProRes codec

Since you're working with 8 bit blu-ray footage (I assume), you want to specifically use "Apple ProRes 422 (HQ)." You can look up how to transcode to ProRes 422HQ in ffmpeg. If you go here and scroll down it shows the command https://ottverse.com/ffmpeg-convert-to-apple-prores-422-4444-hq/ basically you need to specify you want 422 and HQ

There is "data loss" technically, but there will be no visual quality loss. ProRes and DNxHR were designed to be visually lossless and used while editing (which also means it isn't laggy while in the editing software), so they're perfect for doing a fan edit. The only issue is file size, a 2-3 hour movie can be over 100 GB. That is why I recommend using a second hard drive.

When you convert, you can use the original MKV or MP4 file it doesn't matter. Both are containers (like a "folder") and they have the h264 video inside. So I'm a bit confused, did you take the MKV and transcode it again to h264 in an MP4? If yes, then you should go back and use the original MKV. Your MKV file already has h264 inside it, and so you don't need to re-encode it. If you took your MKV and remuxed it into an MP4 with ffmpeg, then no quality was lost and so it's identical to the MKV, which is why earlier I said you could use either to convert to ProRes. As for audio, I always separate it and deal with it later, converting it to 24 bit wavs. Then I can just load in video and audio separately, and they're already lined up so it's good to edit.
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