On Tue, Apr 28, 2026 at 1:02 PM Andrew Randrianasulu <[email protected]> wrote:
On Tue, Apr 28, 2026 at 12:42 PM Georgy Salnikov via Cin <[email protected]> wrote:
On Tue, 28 Apr 2026, Andrea paz via Cin wrote:
1- Regardless of the color space used for the sources, and regardless of the operations we perform on the timeline, do we always see only an sRGB signal on the monitor? Even if the monitor is set to a different color space? I mentioned this in the manual where I had gathered various comments from GG and others, but I can no longer find the sources. Can we see from the code how the signal sent to the monitor works?
I approximately know two cases, they are very different from each others.
1) Conventional (non-HDR) mode. On an uncalibrated monitor you can see anything, although good IPS monitors usually look rather close to sRGB. Generally, to be sure what you see, you must calibrate your monitor with a calorimether device and some calibration software like ArgyllCMS to create the monitor profile.
If you have several non-HDR monitors, each one has ist own profile. CMS software knows, which profile is assigned to which monitor, and knows how not to intermix them.
The reality is yet more complicated.
Usually monitors have various adjustments (brightness, contrast, gamma, color temperature, etc.), laptop panels have backlight power. The computer knows nothing about such adjustments. Should you change anything on the monitor, you must recalibrate it with the new settings.
Calibration profiles can be actualized in different ways. Operating system can do it system-wide (via, for example, colord daemon in KDE, or ArgyllCMS can load its profile via KDE's autostart shotrcuts, etc.). Or some programs can take into account LCMS profiles in their private windows (most photo processing programs like Darktable or Rawtherapee can do that). If, for example, colord has loaded the profile system-wide, and then Gimp corrects colors once again, you can get bad colors corrected twice.
CinGG has no interface to CMS and cannot apply any monitor profiles. If the profile has been loaded by other software, for example, colord has loaded it system-wide, colors from CinGG will be displayed correctly (as sRGB).
I wonder what will happen if you try to view wide-gamut photo on wide-gamut capable monitor *via cingg* ? :)
2) HDR-mode. It is claimed that monitors supporting this mode and switched to this mode are factory-calibrated, profile is saved in firmware, they require no calibration at all, and, moreover, no calibration can be applied to them. Instead, it is claimed that light intensity from pixels be proportional to the pixel values, starting from zero (no light), up to some maximum depending on the actual max brightness of the particular monitor. In this mode, you have that what you have, and can only rely on it.
Ya, HDR10, HDR10+, HLG, Dolby Vision .... xkcd "Standards"
https://www.avsforum.com/threads/checking-for-bt-2020-color-gamut-usage-beyo...
and
https://www.rtings.com/tv/tests/picture-quality/sdr-color-volume
might be relevant (keyword seems to be BT.2020)
Second link does not contain test file, but first one might?
I wonder if something can be rigged via mpv, cingg, ffmpeg + x265 encoding "fake' HDR? I.e. low *dynamic* range, yet still wide color gamut?
https://x265.readthedocs.io/en/2.5/cli.html --master-display <string> SMPTE ST 2086 mastering display color volume SEI info, specified as a string which is parsed when the stream header SEI are emitted. The string format is “G(%hu,%hu)B(%hu,%hu)R(%hu,%hu)WP(%hu,%hu)L(%u,%u)” where %hu are unsigned 16bit integers and %u are unsigned 32bit integers. The SEI includes X,Y display primaries for RGB channels and white point (WP) in units of 0.00002 and max,min luminance (L) values in units of 0.0001 candela per meter square. Applicable for HDR content. Example for a P3D65 1000-nits monitor, where G(x=0.265, y=0.690), B(x=0.150, y=0.060), R(x=0.680, y=0.320), WP(x=0.3127, y=0.3290), L(max=1000, min=0.0001): G(13250,34500)B(7500,3000)R(34000,16000)WP(15635,16450)L(10000000,1) Note that this string value will need to be escaped or quoted to protect against shell expansion on many platforms. No default. ==== I wonder what will happen if you push 1000 nit here down to 100 or something? Will equation/algo/signalling break?
Just hack for consumer mons apparently having no way to display BT2020 SDR video signal ....
CinGG cannot use this mode at all (at least not yet).
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Georgy Salnikov NMR Group Novosibirsk Institute of Organic Chemistry Lavrentjeva, 9, 630090 Novosibirsk, Russia Phone +7-383-3305504 Email [email protected] _______________________________________________________________________________
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