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Merged
ReenigneArcher merged 1 commit into from
Nov 5, 2025
Merged

feat(video): use unified color conversion matrix generator #4387

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2 changes: 1 addition & 1 deletion src/platform/linux/cuda.cu
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Original file line number Diff line number Diff line change
Expand Up @@ -330,7 +330,7 @@ namespace cuda {
}

void sws_t::apply_colorspace(const video::sunshine_colorspace_t &colorspace) {
auto color_p = video::color_vectors_from_colorspace(colorspace);
auto color_p = video::color_vectors_from_colorspace(colorspace, true);
CU_CHECK_IGNORE(cudaMemcpy(color_matrix.get(), color_p, sizeof(video::color_t), cudaMemcpyHostToDevice), "Couldn't copy color matrix to cuda");
}

Expand Down
4 changes: 2 additions & 2 deletions src/platform/linux/graphics.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -698,7 +698,7 @@ namespace egl {
}

void sws_t::apply_colorspace(const video::sunshine_colorspace_t &colorspace) {
auto color_p = video::color_vectors_from_colorspace(colorspace);
auto color_p = video::color_vectors_from_colorspace(colorspace, true);

std::string_view members[] {
util::view(color_p->color_vec_y),
Expand Down Expand Up @@ -811,7 +811,7 @@ namespace egl {
gl::ctx.UseProgram(sws.program[1].handle());
gl::ctx.Uniform1fv(loc_width_i, 1, &width_i);

auto color_p = video::color_vectors_from_colorspace(video::colorspace_e::rec601, false);
auto color_p = video::color_vectors_from_colorspace({video::colorspace_e::rec601, false, 8}, true);
std::pair<const char *, std::string_view> members[] {
std::make_pair("color_vec_y", util::view(color_p->color_vec_y)),
std::make_pair("color_vec_u", util::view(color_p->color_vec_u)),
Expand Down
6 changes: 3 additions & 3 deletions src/platform/windows/display_vram.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -457,12 +457,12 @@ namespace platf::dxgi {
}

void apply_colorspace(const ::video::sunshine_colorspace_t &colorspace) {
auto color_vectors = ::video::color_vectors_from_colorspace(colorspace);
auto color_vectors = ::video::color_vectors_from_colorspace(colorspace, true);

if (format == DXGI_FORMAT_AYUV ||
format == DXGI_FORMAT_R16_UINT ||
format == DXGI_FORMAT_Y410) {
color_vectors = ::video::new_color_vectors_from_colorspace(colorspace);
color_vectors = ::video::color_vectors_from_colorspace(colorspace, false);
}

if (!color_vectors) {
Expand Down Expand Up @@ -775,7 +775,7 @@ namespace platf::dxgi {
BOOST_LOG(warning) << "Failed to increase encoding GPU thread priority. Please run application as administrator for optimal performance.";
}

auto default_color_vectors = ::video::color_vectors_from_colorspace(::video::colorspace_e::rec601, false);
auto default_color_vectors = ::video::color_vectors_from_colorspace({::video::colorspace_e::rec601, false, 8}, true);
if (!default_color_vectors) {
BOOST_LOG(error) << "Missing color vectors for Rec. 601"sv;
return -1;
Expand Down
119 changes: 43 additions & 76 deletions src/video_colorspace.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -120,66 +120,9 @@ namespace video {
return avcodec_colorspace;
}

const color_t *color_vectors_from_colorspace(const sunshine_colorspace_t &colorspace) {
return color_vectors_from_colorspace(colorspace.colorspace, colorspace.full_range);
}

const color_t *color_vectors_from_colorspace(colorspace_e colorspace, bool full_range) {
using float2 = float[2];
auto make_color_matrix = [](float Cr, float Cb, const float2 &range_Y, const float2 &range_UV) -> color_t {
float Cg = 1.0f - Cr - Cb;

float Cr_i = 1.0f - Cr;
float Cb_i = 1.0f - Cb;

float shift_y = range_Y[0] / 255.0f;
float shift_uv = range_UV[0] / 255.0f;

float scale_y = (range_Y[1] - range_Y[0]) / 255.0f;
float scale_uv = (range_UV[1] - range_UV[0]) / 255.0f;
return {
{Cr, Cg, Cb, 0.0f},
{-(Cr * 0.5f / Cb_i), -(Cg * 0.5f / Cb_i), 0.5f, 0.5f},
{0.5f, -(Cg * 0.5f / Cr_i), -(Cb * 0.5f / Cr_i), 0.5f},
{scale_y, shift_y},
{scale_uv, shift_uv},
};
};

static const color_t colors[] {
make_color_matrix(0.299f, 0.114f, {16.0f, 235.0f}, {16.0f, 240.0f}), // BT601 MPEG
make_color_matrix(0.299f, 0.114f, {0.0f, 255.0f}, {0.0f, 255.0f}), // BT601 JPEG
make_color_matrix(0.2126f, 0.0722f, {16.0f, 235.0f}, {16.0f, 240.0f}), // BT709 MPEG
make_color_matrix(0.2126f, 0.0722f, {0.0f, 255.0f}, {0.0f, 255.0f}), // BT709 JPEG
make_color_matrix(0.2627f, 0.0593f, {16.0f, 235.0f}, {16.0f, 240.0f}), // BT2020 MPEG
make_color_matrix(0.2627f, 0.0593f, {0.0f, 255.0f}, {0.0f, 255.0f}), // BT2020 JPEG
};

const color_t *result = nullptr;

switch (colorspace) {
case colorspace_e::rec601:
default:
result = &colors[0];
break;
case colorspace_e::rec709:
result = &colors[2];
break;
case colorspace_e::bt2020:
case colorspace_e::bt2020sdr:
result = &colors[4];
break;
};

if (full_range) {
result++;
}

return result;
}

const color_t *new_color_vectors_from_colorspace(const sunshine_colorspace_t &colorspace) {
constexpr auto generate_color_vectors = [](const sunshine_colorspace_t &colorspace) -> color_t {
const color_t *color_vectors_from_colorspace(const sunshine_colorspace_t &colorspace, bool unorm_output) {
constexpr auto generate_color_vectors = [](const sunshine_colorspace_t &colorspace, bool unorm_output) -> color_t {
// "Table 4 – Interpretation of matrix coefficients (MatrixCoefficients) value" section of ITU-T H.273
double Kr, Kb;
switch (colorspace.colorspace) {
case colorspace_e::rec601:
Expand All @@ -202,7 +145,7 @@ namespace video {
double y_mult, y_add;
double uv_mult, uv_add;

// "Matrix coefficients" section of ITU-T H.273
// "8.3 Matrix coefficients" section of ITU-T H.273
if (colorspace.full_range) {
y_mult = (1 << colorspace.bit_depth) - 1;
y_add = 0;
Expand All @@ -215,9 +158,17 @@ namespace video {
uv_add = (1 << (colorspace.bit_depth - 8)) * 128;
}

// For rounding
y_add += 0.5;
uv_add += 0.5;
if (unorm_output) {
const double unorm_range = (1 << colorspace.bit_depth) - 1;
y_mult /= unorm_range;
y_add /= unorm_range;
uv_mult /= unorm_range;
uv_add /= unorm_range;
} else {
// For rounding
y_add += 0.5f;
uv_add += 0.5f;
}

color_t color_vectors;

Expand Down Expand Up @@ -246,18 +197,31 @@ namespace video {
};

static constexpr color_t colors[] = {
generate_color_vectors({colorspace_e::rec601, false, 8}),
generate_color_vectors({colorspace_e::rec601, true, 8}),
generate_color_vectors({colorspace_e::rec601, false, 10}),
generate_color_vectors({colorspace_e::rec601, true, 10}),
generate_color_vectors({colorspace_e::rec709, false, 8}),
generate_color_vectors({colorspace_e::rec709, true, 8}),
generate_color_vectors({colorspace_e::rec709, false, 10}),
generate_color_vectors({colorspace_e::rec709, true, 10}),
generate_color_vectors({colorspace_e::bt2020, false, 8}),
generate_color_vectors({colorspace_e::bt2020, true, 8}),
generate_color_vectors({colorspace_e::bt2020, false, 10}),
generate_color_vectors({colorspace_e::bt2020, true, 10}),
generate_color_vectors({colorspace_e::rec601, false, 8}, false),
generate_color_vectors({colorspace_e::rec601, true, 8}, false),
generate_color_vectors({colorspace_e::rec601, false, 10}, false),
generate_color_vectors({colorspace_e::rec601, true, 10}, false),
generate_color_vectors({colorspace_e::rec709, false, 8}, false),
generate_color_vectors({colorspace_e::rec709, true, 8}, false),
generate_color_vectors({colorspace_e::rec709, false, 10}, false),
generate_color_vectors({colorspace_e::rec709, true, 10}, false),
generate_color_vectors({colorspace_e::bt2020, false, 8}, false),
generate_color_vectors({colorspace_e::bt2020, true, 8}, false),
generate_color_vectors({colorspace_e::bt2020, false, 10}, false),
generate_color_vectors({colorspace_e::bt2020, true, 10}, false),

generate_color_vectors({colorspace_e::rec601, false, 8}, true),
generate_color_vectors({colorspace_e::rec601, true, 8}, true),
generate_color_vectors({colorspace_e::rec601, false, 10}, true),
generate_color_vectors({colorspace_e::rec601, true, 10}, true),
generate_color_vectors({colorspace_e::rec709, false, 8}, true),
generate_color_vectors({colorspace_e::rec709, true, 8}, true),
generate_color_vectors({colorspace_e::rec709, false, 10}, true),
generate_color_vectors({colorspace_e::rec709, true, 10}, true),
generate_color_vectors({colorspace_e::bt2020, false, 8}, true),
generate_color_vectors({colorspace_e::bt2020, true, 8}, true),
generate_color_vectors({colorspace_e::bt2020, false, 10}, true),
generate_color_vectors({colorspace_e::bt2020, true, 10}, true),
};

const color_t *result = nullptr;
Expand All @@ -282,6 +246,9 @@ namespace video {
if (colorspace.full_range) {
result += 1;
}
if (unorm_output) {
result += 12;
}

return result;
}
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15 changes: 5 additions & 10 deletions src/video_colorspace.h
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Original file line number Diff line number Diff line change
Expand Up @@ -48,20 +48,15 @@ namespace video {
float range_uv[2];
};

const color_t *color_vectors_from_colorspace(const sunshine_colorspace_t &colorspace);

const color_t *color_vectors_from_colorspace(colorspace_e colorspace, bool full_range);

/**
* @brief New version of `color_vectors_from_colorspace()` function that better adheres to the standards.
* Returned vectors are used to perform RGB->YUV conversion.
* Unlike its predecessor, color vectors will produce output in `UINT` range, not `UNORM` range.
* Input is still in `UNORM` range. Returned vectors won't modify color primaries and color
* transfer function.
* @brief Get static RGB->YUV color conversion matrix.
* This matrix expects RGB input in UNORM (0.0 to 1.0) range and doesn't perform any
* gamut mapping or gamma correction.
* @param colorspace Targeted YUV colorspace.
* @param unorm_output Whether the matrix should produce output in UNORM or UINT range.
* @return `const color_t*` that contains RGB->YUV transformation vectors.
* Components `range_y` and `range_uv` are there for backwards compatibility
* and can be ignored in the computation.
*/
const color_t *new_color_vectors_from_colorspace(const sunshine_colorspace_t &colorspace);
const color_t *color_vectors_from_colorspace(const sunshine_colorspace_t &colorspace, bool unorm_output);
} // namespace video
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