Re: [PATCH v12 13/15] drm/vkms: Create KUnit tests for YUV conversions

[Louis Chauvet]

Hi, 

> > + * The YUV color representation were acquired via the colour python framework.
> > + * Below are the function calls used for generating each case.
> > + *
> > + * For more information got to the docs:
> > + * https://colour.readthedocs.io/en/master/generated/colour.RGB_to_YCbCr.html
> > + */
> > +static struct yuv_u8_to_argb_u16_case yuv_u8_to_argb_u16_cases[] = {
> > +	/*
> > +	 * colour.RGB_to_YCbCr(<rgb color in 16 bit form>,
> > +	 *                     K=colour.WEIGHTS_YCBCR["ITU-R BT.601"],
> > +	 *                     in_bits = 16,
> > +	 *                     in_legal = False,
> > +	 *                     in_int = True,
> > +	 *                     out_bits = 8,
> > +	 *                     out_legal = False,
> > +	 *                     out_int = True)
> > +	 */
> 
> We should really detail what the intent and expected outcome is supposed
> to be here. Relying on a third-party python library call for
> documentation isn't great.
> 
> Maxime

This was requested by Pekka in the [v2] of this series.

I can add something like this before each tests, but I think having the 
exact python code used may help people to understand what should be the 
behavior, and refering to the python code to understand the conversion.

I can add something like this before each tests to clarify the tested 
case:

	Test cases for conversion between YUV BT601 limited range and 
	RGB using the ITU-R BT.601 weights.

Or maybe just documenting the structure yuv_u8_to_argb_u16_case:

	@encoding: Encoding used to convert RGB to YUV
	@range: Range used to convert RGB to YUV
	@n_colors: Count of test colors in this case
	@format_pair.name: Name used for this color conversion, used to 
			   clarify the test results
	@format_pair.rgb: RGB color tested
	@format_pair.yuv: Same color as @format_pair.rgb, but converted to 
			  YUV using @encoding and @range.

What do you think?

Thanks,
Louis Chauvet

[v2]:https://lore.kernel.org/all/20240229141238.51891cad.pekka.paalanen@xxxxxxxxxxxxx/
[v5]:https://lore.kernel.org/all/20240328152631.63af0e8c.pekka.paalanen@xxxxxxxxxxxxx/