3.6 Multimedia systems colorimetric characteristics

IEC 61966-2-1 3.11 sRGB

Reference display image characteristics

Display luminance level

80 cd/m²

Display model offset (R, G and B)

0.0

Display input/output characteristics (R, G and B)

2.2

Display primaries

x

y

Red

0.640

0.330

Green

0.300

0.600

Blue

0.150

0.060

White D65

0.3127

0.3290

Reference viewing conditions

Reference background

Background relative luminance is equal to 20 % reference display luminance level (16 cd/m²) for background as a part of display monitor; chromaticity coordinates are about x = 0.3127, y = 0.3290 (D65).

Reference surround

20 % reference luminance level of reference surround (4.1 cd/m²); chromaticity coordinates are about x = 0.3457, y = 0.3585 (D50).

Reference proximal field

20 % reference luminance level of display monitor (16 cd/m²); chromaticity coordinates are about x = 0.3127, y = 0.3290 (D65).

Reference ambient illuminance level

64 lx

Reference ambient white point

x = 0.3457, y = 0.3585 (D50).

Reference veiling glare

0.2 cd/m²

Transformation from RGB values to CIE 1931 XYZ values

where

For black digital count KDC = 0 and a white digital count WDC = 255 for 8-bit/channel encoding:

If then:

If then:

Transformation from CIE 1931 XYZ values to RGB values

Note: In the RGB encoding process, negative sRGB tristimulus values and sRGB tristimulus values greater than 1.00 are not retained. The luminance dynamic range and color gamut of RGB is limited to the tristimulus values between 0.0 and 1.0 by simple clipping.

If then:

or if then:

For KDC = 0 and WDC = 255 for 8-bit/channel encoding:

Transformation from sYCC to СІЕ 1931 XYZ values

For 8-bit/channel encoding :

8-bit/channel encoding shall be the default sYCC encoding bit depth. Other bit depths may be unsupported for general use.

For N-bit/channel encoding (N > 8):

For 8-bit/channel encoding: