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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include shared
#define YUV_FORMAT_NV12 0
#define YUV_FORMAT_P010 1
#define YUV_FORMAT_PLANAR 2
#define YUV_FORMAT_INTERLEAVED 3
//#define YUV_PRECISION mediump
#define YUV_PRECISION highp
#ifdef WR_VERTEX_SHADER
#ifdef WR_FEATURE_TEXTURE_RECT
#define TEX_SIZE_YUV(sampler) vec2(1.0)
#else
#define TEX_SIZE_YUV(sampler) vec2(TEX_SIZE(sampler).xy)
#endif
// `YuvRangedColorSpace`
#define YUV_COLOR_SPACE_REC601_NARROW 0
#define YUV_COLOR_SPACE_REC601_FULL 1
#define YUV_COLOR_SPACE_REC709_NARROW 2
#define YUV_COLOR_SPACE_REC709_FULL 3
#define YUV_COLOR_SPACE_REC2020_NARROW 4
#define YUV_COLOR_SPACE_REC2020_FULL 5
#define YUV_COLOR_SPACE_GBR_IDENTITY 6
// The constants added to the Y, U and V components are applied in the fragment shader.
// `rgbFromYuv` from https://jdashg.github.io/misc/colors/from-coeffs.html
// The matrix is stored in column-major.
const mat3 RgbFromYuv_Rec601 = mat3(
1.00000, 1.00000, 1.00000,
0.00000,-0.17207, 0.88600,
0.70100,-0.35707, 0.00000
);
const mat3 RgbFromYuv_Rec709 = mat3(
1.00000, 1.00000, 1.00000,
0.00000,-0.09366, 0.92780,
0.78740,-0.23406, 0.00000
);
const mat3 RgbFromYuv_Rec2020 = mat3(
1.00000, 1.00000, 1.00000,
0.00000,-0.08228, 0.94070,
0.73730,-0.28568, 0.00000
);
// The matrix is stored in column-major.
// Identity is stored as GBR
const mat3 RgbFromYuv_GbrIdentity = mat3(
0.0 , 1.0, 0.0,
0.0 , 0.0, 1.0,
1.0 , 0.0, 0.0
);
// -
struct YuvPrimitive {
int channel_bit_depth;
int color_space;
int yuv_format;
};
struct YuvColorSamplingInfo {
mat3 rgb_from_yuv;
vec4 packed_zero_one_vals;
};
struct YuvColorMatrixInfo {
vec3 ycbcr_bias;
mat3 rgb_from_debiased_ycbrc;
};
// -
vec4 yuv_channel_zero_one_identity(int bit_depth, float channel_max) {
float all_ones_normalized = float((1 << bit_depth) - 1) / channel_max;
return vec4(0.0, 0.0, all_ones_normalized, all_ones_normalized);
}
vec4 yuv_channel_zero_one_narrow_range(int bit_depth, float channel_max) {
// Note: 512/1023 != 128/255
ivec4 zero_one_ints = ivec4(16, 128, 235, 240) << (bit_depth - 8);
return vec4(zero_one_ints) / channel_max;
}
vec4 yuv_channel_zero_one_full_range(int bit_depth, float channel_max) {
vec4 narrow = yuv_channel_zero_one_narrow_range(bit_depth, channel_max);
vec4 identity = yuv_channel_zero_one_identity(bit_depth, channel_max);
return vec4(0.0, narrow.y, identity.z, identity.w);
}
YuvColorSamplingInfo get_yuv_color_info(YuvPrimitive prim) {
float channel_max = 255.0;
if (prim.channel_bit_depth > 8) {
if (prim.yuv_format == YUV_FORMAT_P010) {
// This is an MSB format.
channel_max = float((1 << prim.channel_bit_depth) - 1);
} else {
// For >8bpc, we get the low bits, not the high bits:
// 10bpc(1.0): 0b0000_0011_1111_1111
channel_max = 65535.0;
}
}
if (prim.color_space == YUV_COLOR_SPACE_REC601_NARROW) {
return YuvColorSamplingInfo(RgbFromYuv_Rec601,
yuv_channel_zero_one_narrow_range(prim.channel_bit_depth, channel_max));
} else if (prim.color_space == YUV_COLOR_SPACE_REC601_FULL) {
return YuvColorSamplingInfo(RgbFromYuv_Rec601,
yuv_channel_zero_one_full_range(prim.channel_bit_depth, channel_max));
} else if (prim.color_space == YUV_COLOR_SPACE_REC709_NARROW) {
return YuvColorSamplingInfo(RgbFromYuv_Rec709,
yuv_channel_zero_one_narrow_range(prim.channel_bit_depth, channel_max));
} else if (prim.color_space == YUV_COLOR_SPACE_REC709_FULL) {
return YuvColorSamplingInfo(RgbFromYuv_Rec709,
yuv_channel_zero_one_full_range(prim.channel_bit_depth, channel_max));
} else if (prim.color_space == YUV_COLOR_SPACE_REC2020_NARROW) {
return YuvColorSamplingInfo(RgbFromYuv_Rec2020,
yuv_channel_zero_one_narrow_range(prim.channel_bit_depth, channel_max));
} else if (prim.color_space == YUV_COLOR_SPACE_REC2020_FULL) {
return YuvColorSamplingInfo(RgbFromYuv_Rec2020,
yuv_channel_zero_one_full_range(prim.channel_bit_depth, channel_max));
} else {
// Identity
return YuvColorSamplingInfo(RgbFromYuv_GbrIdentity,
yuv_channel_zero_one_identity(prim.channel_bit_depth, channel_max));
}
}
YuvColorMatrixInfo get_rgb_from_ycbcr_info(YuvPrimitive prim) {
YuvColorSamplingInfo info = get_yuv_color_info(prim);
vec2 zero = info.packed_zero_one_vals.xy;
vec2 one = info.packed_zero_one_vals.zw;
// Such that yuv_value = (ycbcr_sample - zero) / (one - zero)
vec2 scale = 1.0 / (one - zero);
YuvColorMatrixInfo mat_info;
mat_info.ycbcr_bias = zero.xyy;
mat3 yuv_from_debiased_ycbcr = mat3(scale.x, 0.0, 0.0,
0.0, scale.y, 0.0,
0.0, 0.0, scale.y);
mat_info.rgb_from_debiased_ycbrc = info.rgb_from_yuv * yuv_from_debiased_ycbcr;
return mat_info;
}
void write_uv_rect(
vec2 uv0,
vec2 uv1,
vec2 f,
vec2 texture_size,
out vec2 uv,
out vec4 uv_bounds
) {
uv = mix(uv0, uv1, f);
uv_bounds = vec4(uv0 + vec2(0.5), uv1 - vec2(0.5));
#ifndef WR_FEATURE_TEXTURE_RECT
uv /= texture_size;
uv_bounds /= texture_size.xyxy;
#endif
}
#endif
#ifdef WR_FRAGMENT_SHADER
vec4 sample_yuv(
int format,
YUV_PRECISION vec3 ycbcr_bias,
YUV_PRECISION mat3 rgb_from_debiased_ycbrc,
vec2 in_uv_y,
vec2 in_uv_u,
vec2 in_uv_v,
vec4 uv_bounds_y,
vec4 uv_bounds_u,
vec4 uv_bounds_v
) {
YUV_PRECISION vec3 ycbcr_sample;
switch (format) {
case YUV_FORMAT_PLANAR:
{
// The yuv_planar format should have this third texture coordinate.
vec2 uv_y = clamp(in_uv_y, uv_bounds_y.xy, uv_bounds_y.zw);
vec2 uv_u = clamp(in_uv_u, uv_bounds_u.xy, uv_bounds_u.zw);
vec2 uv_v = clamp(in_uv_v, uv_bounds_v.xy, uv_bounds_v.zw);
ycbcr_sample.x = TEX_SAMPLE(sColor0, uv_y).r;
ycbcr_sample.y = TEX_SAMPLE(sColor1, uv_u).r;
ycbcr_sample.z = TEX_SAMPLE(sColor2, uv_v).r;
}
break;
case YUV_FORMAT_NV12:
case YUV_FORMAT_P010:
{
vec2 uv_y = clamp(in_uv_y, uv_bounds_y.xy, uv_bounds_y.zw);
vec2 uv_uv = clamp(in_uv_u, uv_bounds_u.xy, uv_bounds_u.zw);
ycbcr_sample.x = TEX_SAMPLE(sColor0, uv_y).r;
ycbcr_sample.yz = TEX_SAMPLE(sColor1, uv_uv).rg;
}
break;
case YUV_FORMAT_INTERLEAVED:
{
// "The Y, Cb and Cr color channels within the 422 data are mapped into
// the existing green, blue and red color channels."
// https://www.khronos.org/registry/OpenGL/extensions/APPLE/APPLE_rgb_422.txt
vec2 uv_y = clamp(in_uv_y, uv_bounds_y.xy, uv_bounds_y.zw);
ycbcr_sample = TEX_SAMPLE(sColor0, uv_y).gbr;
}
break;
default:
ycbcr_sample = vec3(0.0);
break;
}
//if (true) return vec4(ycbcr_sample, 1.0);
// See the YuvColorMatrix definition for an explanation of where the constants come from.
YUV_PRECISION vec3 rgb = rgb_from_debiased_ycbrc * (ycbcr_sample - ycbcr_bias);
#if defined(WR_FEATURE_ALPHA_PASS) && defined(SWGL_CLIP_MASK)
// Avoid out-of-range RGB values that can mess with blending. These occur due to invalid
// YUV values outside the mappable space that never the less can be generated.
rgb = clamp(rgb, 0.0, 1.0);
#endif
return vec4(rgb, 1.0);
}
#endif
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