Stuck on an issue?

Description

rgb_to_ycbcr can give cb and cr values outside the defined out bit range when outputting to full range. If I feed it with 100% red the function return 1024 for the red channel, which is of course outside the range of 10 bits.

I believe that this is caused by these lines of code: ycbcr.py:147

    if is_int and not is_legal:
        ranges[3] = 2**bits

I think the fix would be just to remove these lines, but since it looks so intentional I’ll leave it to the maintainer.

Actually, thinking about it again, the correct solution would be to set ranges[2] to 1. Rec.2100, which addresses full range on page 10. https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.2100-2-201807-I!!PDF-E.pdf

Which means my suggestion is that we should make this fix: ycbcr.py:147

    if is_int and not is_legal:
        ranges[2] = 1

Code for Reproduction

import colour

rgb = (1.0, 0, 0)
y, cb, cr = colour.RGB_to_YCbCr(rgb, in_int=False, in_legal=False, out_bits=10, out_legal=False, out_int=True)
print(y, cb, cr)
# >> 217 395 1024

Exception Message

No response

Environment Information

>>> import colour; colour.utilities.describe_environment()
===============================================================================
*                                                                             *
*   Interpreter :                                                             *
*       python : 3.9.6 (default, Sep 26 2022, 11:37:49)                       *
*                [Clang 14.0.0 (clang-1400.0.29.202)]                         *
*                                                                             *
*   colour-science.org :                                                      *
*       colour : 0.4.1                                                        *
*                                                                             *
*   Runtime :                                                                 *
*       imageio : 2.22.3                                                      *
*       numpy : 1.23.4                                                        *
*       scipy : 1.9.3                                                         *
*                                                                             *
===============================================================================
defaultdict(<class 'dict'>, {'Interpreter': {'python': '3.9.6 (default, Sep 26 2022, 11:37:49) \n[Clang 14.0.0 (clang-1400.0.29.202)]'}, 'colour-science.org': {'colour': '0.4.1'}, 'Runtime': {'imageio': '2.22.3', 'numpy': '1.23.4', 'scipy': '1.9.3'}})