Was working on this the past week and want to report back that I was able to get good results using hdr.tar file from Andrew and following Andrea's testing. But I still want to do more testing because I could not get the small_empty_room_1_4k.exr example to give me the same kind of results as Andrea displayed in his mp4 demo.

And I do not know how to test the patch provided by Andrew for overlayframe.h. I am wondering if for now, if it would be sufficient to only apply the color3way and histogram patches and not the overlayframe.h patch (I did test color3way once without overlayframe.h patch and it seemed to work the same) because overlayframe.h is included in quite a few routines. I do need to do more tests also, because when testing using HDR_111_Parking_Lot_2.zip file, HDR_111_Parking_Lot_2_Ref.hdr, my laptop completely powered off 3 times when I cranked the Value all the way to the right in Histogram. However, this laptop has a bad memory bank so I suspect that was the cause.

More later.

Thanks to Andrew's patch I was able to create an AppImage that has no
clipping when using RGBA-FLOAT in X11. I thought of uploading it to
Dropbox (I apologize for the security, if you want and request me I
will try to upload it to transfer.sh). If you want to test it you are
free to download it. One caveat: I created it on my Arch Linux, which
is a Rolling, and I don't know if this leads to problems with the
appimage working on other distros. It doesn't give me any problems on
Arch.

https://www.dropbox.com/scl/fi/eku6sto8nxapws4qxjri8/cin-HDR.AppImage?rlkey=mj8uy3jv1gufzc79s70zjckd8&dl=0