[igt-dev] [PATCH i-g-t 1/3] lib/igt_fb: round rgb->yuv conversion results

[Kamil Konieczny]

Hi Swati,

On 2023-05-31 at 13:15:28 +0530, Swati Sharma wrote:
> Round rgb->yuv conversion results.
> 
> Signed-off-by: Ville Syrjala <ville.syrjala at linux.intel.com>
> Signed-off-by: Swati Sharma <swati2.sharma at intel.com>
> ---
>  lib/igt_fb.c | 25 +++++++++++++++----------
>  1 file changed, 15 insertions(+), 10 deletions(-)
> 
> diff --git a/lib/igt_fb.c b/lib/igt_fb.c
> index 71a199d4..11a5d6c0 100644
> --- a/lib/igt_fb.c
> +++ b/lib/igt_fb.c
> @@ -3064,11 +3064,16 @@ static void igt_fb_destroy_cairo_shadow_buffer(struct igt_fb *shadow,
>  	munmap(ptr, shadow->size);
>  }
>  
> -static uint8_t clamprgb(float val)
> +static uint8_t clamp8(float val)
>  {
>  	return clamp((int)(val + 0.5f), 0, 255);
>  }
>  
> +static uint8_t clamp16(float val)
------------- ^
imho this should be 16, uint16_t as name suggest and
following range is 64K ?

> +{
> +	return clamp((int)(val + 0.5f), 0, 65535);
------------------------------------------ ^
This is 64K.

Regards,
Kamil

> +}
> +
>  static void read_rgb(struct igt_vec4 *rgb, const uint8_t *rgb24)
>  {
>  	rgb->d[0] = rgb24[2];
> @@ -3079,9 +3084,9 @@ static void read_rgb(struct igt_vec4 *rgb, const uint8_t *rgb24)
>  
>  static void write_rgb(uint8_t *rgb24, const struct igt_vec4 *rgb)
>  {
> -	rgb24[2] = clamprgb(rgb->d[0]);
> -	rgb24[1] = clamprgb(rgb->d[1]);
> -	rgb24[0] = clamprgb(rgb->d[2]);
> +	rgb24[2] = clamp8(rgb->d[0]);
> +	rgb24[1] = clamp8(rgb->d[1]);
> +	rgb24[0] = clamp8(rgb->d[2]);
>  }
>  
>  struct fb_convert_buf {
> @@ -3401,7 +3406,7 @@ static void convert_rgb24_to_yuv(struct fb_convert *cvt)
>  
>  			rgb_tmp += bpp;
>  
> -			*y_tmp = yuv.d[0];
> +			*y_tmp = clamp8(yuv.d[0]);
>  			y_tmp += params.ay_inc;
>  
>  			if ((i % dst_fmt->vsub) || (j % dst_fmt->hsub))
> @@ -3431,8 +3436,8 @@ static void convert_rgb24_to_yuv(struct fb_convert *cvt)
>  			read_rgb(&pair_rgb, pair_rgb24);
>  			pair_yuv = igt_matrix_transform(&m, &pair_rgb);
>  
> -			*u_tmp = (yuv.d[1] + pair_yuv.d[1]) / 2.0f;
> -			*v_tmp = (yuv.d[2] + pair_yuv.d[2]) / 2.0f;
> +			*u_tmp = clamp8((yuv.d[1] + pair_yuv.d[1]) / 2.0f);
> +			*v_tmp = clamp8((yuv.d[2] + pair_yuv.d[2]) / 2.0f);
>  
>  			u_tmp += params.uv_inc;
>  			v_tmp += params.uv_inc;
> @@ -3590,7 +3595,7 @@ static void convert_float_to_yuv16(struct fb_convert *cvt, bool alpha)
>  
>  			rgb_tmp += fpp;
>  
> -			*y_tmp = yuv.d[0];
> +			*y_tmp = clamp16(yuv.d[0]);
>  			y_tmp += params.ay_inc;
>  
>  			if ((i % dst_fmt->vsub) || (j % dst_fmt->hsub))
> @@ -3620,8 +3625,8 @@ static void convert_float_to_yuv16(struct fb_convert *cvt, bool alpha)
>  			read_rgbf(&pair_rgb, pair_float);
>  			pair_yuv = igt_matrix_transform(&m, &pair_rgb);
>  
> -			*u_tmp = (yuv.d[1] + pair_yuv.d[1]) / 2.0f;
> -			*v_tmp = (yuv.d[2] + pair_yuv.d[2]) / 2.0f;
> +			*u_tmp = clamp16((yuv.d[1] + pair_yuv.d[1]) / 2.0f);
> +			*v_tmp = clamp16((yuv.d[2] + pair_yuv.d[2]) / 2.0f);
>  
>  			u_tmp += params.uv_inc;
>  			v_tmp += params.uv_inc;
> -- 
> 2.25.1
>