MPEG Streamclip not showing Apple ProRes 422 HQ

Yes you have to have installed a suitable Apple pro app to get the ProRes codec.

MPEGStreamClip is long discontinued, both the Mac version and the Windows version use 'classic' QuickTime. Classic QuickTime (not its official name but cognoscenti should know what I mean) was discontinued for Windows in 2016, rumours are that it will be discontinued for Mac this year when the next version of macOS is released.

So, you would then only be able to run MPEGStreamclip via an older version of macOS.

I still use MPEGStreamClip occasionally myself, it is great for editing both MPEG2 files and even MPEG4 aka H.264 files, it can do so without having to re-encode the video unlike Apple's own tools.

I would not be too surprised if QuickTime Player also got discontinued, whilst it often has smoother playback than VLC it is otherwise far less useful.

Just a guess but MPEG Streamclip 1.9.3b8 is over 6 years old.

IINA looks promising, I had seen it some months ago, but I get the impression it still does not support things like DVD and BluRay menus if you are playing discs or ISO images.

I keep meaning to test it, I will try and remember to do so at the weekend. I could then also test some things that in the past VLC failed on but eventually fixed. :)

Sorry, I assumed you had them installed since you were asking why they weren't showing.

FWIW. you may want to take a look at IINA as an alternative to VLC. As far as this thread, I felt like someone was asking "Have you seen my cat?" when they didn't own one. 😎

I have no way to test Blu-rays since I've never owned any. We do have a Blu-ray player for the TV. Never used of course.