I'm a big fan of high dynamic range capture and processing. As we all know, right now the 4K HDRX is not there on Scarlet.
I think I have a solution that is a slight modification of the scheme that Red currently is using.
This method relieves the compression overhead of the X track by only compressing the actual highlights that are
useful in the subsequent processing ( blending or toning ) of the two tracks.
It has been indicated that the processing limits the HDRX frame rates. Understandable as it has to compress double the number of frames!
If the code is allowed to skip over a threshold for localized brightness, much of a frame does not have to be compressed at all. In a crude sense this is a form of compression in itself ... a rather harsh quantizer, as it were...
The scene turns into almost all 'bright stuff' that overload the X track compression anyway. Possible solution is to reduce compression of the A track as well, via a similar RLE or skipping strategy. After all, you only really need image from one track or another. Overlap a little for transition areas.
The simple 'blend' RCX HDR fails. Yes, that would have to be updated for this new mode. Perhaps to true high bit depth HDR that still guys use.
I worked up a little video to help show this. The above may make more sense after seeing the video. The result at the end was actually processed from the reduced compression requirement X track with a normal A track. You really don't need those dark X track pixels anyway! So why compress them ?
Comments are welcome!