The tool converts RGB values between color spaces.
Enter the chromaticity coordinates for the source and destination color space or select from the predefined set. Next, pick the EOTF (electro-optical transfer function).
If the source white differs from the destination white point, the selection of the chromatic adaptation transform (CAT) is relevant. The options are the CAT02 transform and the Bradford transform. Without a CAT, which is the the third choice, the balance of the RGB values will change.
In the table at the bottom of the page, enter the R, G, and B values in the left column (labeled SRC'). These are the non-linear values, e.g. the signal values sent to a monitor. The next columns are
- SRC
- The linear RGB values in the source color space.
- XYZ
- The XYZ tristimulus values (CIE 1931) adapted to the white of the target color space (if a CAT is selected, see above).
- xyY
- The CIE chromaticity coordinates (xy) and the relative luminance (Y, same value as in XYZ).
- DST
- The linear RGB values in the target color space. If the color is out of gamut, values may be less than 0 or greater than 1.
- DST'
- The non-linear values in the target color space. Values outside of the
range [0,1] are clamped.
For the conversion between SDR (Standard Dynamic Range) and HDR (High Dynamic Range) colorspaces the following is assumed.
- The conversion is based on absolute luminance.
- SDR peak luminance is at 100 cd/m2 (nits).
- A linear value of 1.0 is represented at 100 cd/m2 (nits).
- HLG (Hybrid Log Gamma) peak luminance is at 1000 cd/m2 (nits). The HLG gamma is 1.2.
