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[mattkhan]

https://github.com/3ll3d00d/mwcapture

latest release can be found here -> https://github.com/3ll3d00d/mwcapture/releases

this is a directshow filter that enables use of a magewell pro card (https://www.magewell.com/products/pro-capture-hdmi-4k-plus) in MC (and other directshow apps)

you can use such cards in MC without this filter so the differentiation comes from

* will automatically try to handle signal changes, mainly this means from SDR to HDR and back (NB: actual support depends on the renderer, JRVR does support this so all good for MC)
* can handle multichannel audio

limitations noted on the linked github inc

* only tested on my system
* multichannel audio channel layout is a ? atm (I need to test more)
* I think changing audio format is technically supported by my filter but MC (as far as I know) does not this on the fly so it's probably a moot point

code is publicly available as is the build recipe, if feeling paranoid then feel free to build it yourself

note that this is a 1st release, it does seem functional (ignore the multichannel audio bit) to me but I think anyone using it should go in expecting problems & be prepared to provide logs to explain what they see (using one of the non release builds)

[Lep334]

So does this work like videoprocessor works for Madvr?

[mattkhan]

So does this work like videoprocessor works for Madvr?

Yes you could use it that way (though this is driven by the metadata in the stream rather than user choice)

[mattkhan]

NB: the key difference being you're not pinned to a renderer with an unknown future (madvr)

[mattkhan]

Now that video seems done, continuing to work on multichannel pcm, and audio format negotiation. I eventually realised that the channel mapping in cea-861 is different to usual output formats so I need to add some logic to handle whatever is in the audio hdmi infoframe.

[Lep334]

NB: the key difference being you're not pinned to a renderer with an unknown future (madvr)

That is definitely exciting.  Will keep an eye on this for sure

[mattkhan]

It basically works now as far as I can see so you just need a card to test it out

[mattkhan]

for audio, I found https://learn.microsoft.com/en-us/windows/win32/coreaudio/representing-formats-for-iec-61937-transmissions which looks like it corresponds to the info in 6.6.1 of https://ia903006.us.archive.org/11/items/CEA-861-E/CEA-861-E.pdf (HDMI audioframe) so I guess I should be able to try to send such encoded content from my filter in the right format, whether it works or not is probably something that's going to take a bit of time to test out

[mattkhan]

Looks like https://ffmpeg.org/doxygen/trunk/spdifdec_8c_source.html#l00189 is what is needed to determine the contents of the bitstream

[mattkhan]

Managed to successfully receive ac3, now to work out how to push that through mc