MPC-HC color management comparison

[darkbasic]

http://darkbasic.homelinux.com/images/vid-col-man-comparison.jpg

You may need a very wide gamut monitor to see all the differences, because mine is larger than AdobeRGB and I did not check how wide the gamut of the image is. Profile is embedded, color depth 8 bit/channel because of gimp users unable to view 16 bit/channel images. Do not use firefox to view it, because since they stopped using LCM it sucks hard.

First of all: how it's possible that there is no difference between MCP-HC color management using HDTV and SDTV NTSC input type?

I dumped the wtpt, rXYZ, gXYZ and bXYZ tags form my monitor's profile, found the white point and chromatic adaptated rXYZ, gXYZ and bXYZ to find the primaries. Finally I made a shader with the shader editor (http://www.avsforum.com/avs-vb/showthread.php?t=912720) to color correct from SMPTE-C (the color space is supposed to be SMPTE-C, film is 10000BC 1080p). Why is the difference between the shader editor solution and MPC-HC emedded color management so huge?


I still did not test neither madvr nor cr3dlut. Which one is supposed to be the best? I did not find much documentation about cr3dlut...

Thank you,
Darkbasic

[mariush]

Well, maybe if you save the picture in a format that doesn't alter the colors, we'd tell. Saving to JPG quality 6 (between 1 and 10), probably also 4:2:0 or 4:2:2 doesn't help. What's wrong with PNG

Did you check what color primaries are specified in the MKV file?

[darkbasic]

Is isn't jpeg quality 6, it's photoshop's maximum jpeg quality and it doesn't alter any color in a significant manner, I compared it with the original lossless file. I didn't use png because it was useless and because jpeg allows me to save bandwidth on my home server.

Did you check what color primaries are specified in the MKV file?
How to?

[dansrfe]

dude, it doesn't matter. You asked such a technical question that we NEED to see the lossless.

[darkbasic]

I don't have the lossless anymore, anyway I will make another example tomorrow if you want.
I checked the SDTV_NTSC.icc and SMPTE_C.icc photoshop profiles and they seem to be quite different, so this may explain the differences between MPC-HC and shader editor: I just assumed two completely different source gamuts.
But MPC-HC being unable to color manage an SMPTE-C source it's quite strange...
What's even more strange is that SDTV_NTSC.icc and HDTV_rec709.icc are very similar, they seems the same profile... (but this explain why MPC-HC gives the same result with both).

Anyway, assuming SDTV_NTSC as source gamut, I compared an MPC-HC color managed frame with a frame color corrected with photoshop: I noticed MPC-HC having much more contrast, giving less detailed dark zones.
Here is a screenshot (lossless):
http://darkbasic.homelinux.com/images/ps-vs-mpchc.png