A bit on pricely side... (~900 usd) but in theory should be supported by out-of-tree v4l2 (gpl2) driver..
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Features
4K/UltraHD/2K/HD/SD up to 50/60p
4x full-size HDMI inputs each with 8-channel embedded audio
HDMI 2.0 (port 1 & 2) and HDMI 1.4b (ports 3 & 4)
RGB 4:4:4 12-bit, YCbCr 4:2:2 10-bit and HFR workflows supported
Simultaneous capture of 2x 4K/UltraHD or 4x 2K/HD
Capture stunning HDR from cameras, game consoles, and more
PQ, HLG, HDR10 and Dolby Vision Support*
HDR Metadata Capture
Video4Linux (V4L2) and DirectShow support
Compatible with leading creative apps such as Telestream® Wirecast®, vMix® and more
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of course it will be interesting to know if such card/driver actually work with CinGG's v4l2 capture implementation....