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256/**
* @file src/video_colorspace.cpp
* @brief Definitions for colorspace functions.
*/
// this include
#include "video_colorspace.h"
// local includes
#include "logging.h"
#include "video.h"
extern "C" {
#include <libswscale/swscale.h>
}
namespace video {
bool colorspace_is_hdr(const sunshine_colorspace_t &colorspace) {
return colorspace.colorspace == colorspace_e::bt2020;
}
sunshine_colorspace_t colorspace_from_client_config(const config_t &config, bool hdr_display) {
sunshine_colorspace_t colorspace;
/* See video::config_t declaration for details */
if (config.dynamicRange > 0 && hdr_display) {
// Rec. 2020 with ST 2084 perceptual quantizer
colorspace.colorspace = colorspace_e::bt2020;
} else {
switch (config.encoderCscMode >> 1) {
case 0:
// Rec. 601
colorspace.colorspace = colorspace_e::rec601;
break;
case 1:
// Rec. 709
colorspace.colorspace = colorspace_e::rec709;
break;
case 2:
// Rec. 2020
colorspace.colorspace = colorspace_e::bt2020sdr;
break;
default:
BOOST_LOG(error) << "Unknown video colorspace in csc, falling back to Rec. 709";
colorspace.colorspace = colorspace_e::rec709;
break;
}
}
colorspace.full_range = (config.encoderCscMode & 0x1);
switch (config.dynamicRange) {
case 0:
colorspace.bit_depth = 8;
break;
case 1:
colorspace.bit_depth = 10;
break;
default:
BOOST_LOG(error) << "Unknown dynamicRange value, falling back to 10-bit color depth";
colorspace.bit_depth = 10;
break;
}
if (colorspace.colorspace == colorspace_e::bt2020sdr && colorspace.bit_depth != 10) {
BOOST_LOG(error) << "BT.2020 SDR colorspace expects 10-bit color depth, falling back to Rec. 709";
colorspace.colorspace = colorspace_e::rec709;
}
return colorspace;
}
avcodec_colorspace_t avcodec_colorspace_from_sunshine_colorspace(const sunshine_colorspace_t &sunshine_colorspace) {
avcodec_colorspace_t avcodec_colorspace;
switch (sunshine_colorspace.colorspace) {
case colorspace_e::rec601:
// Rec. 601
avcodec_colorspace.primaries = AVCOL_PRI_SMPTE170M;
avcodec_colorspace.transfer_function = AVCOL_TRC_SMPTE170M;
avcodec_colorspace.matrix = AVCOL_SPC_SMPTE170M;
avcodec_colorspace.software_format = SWS_CS_SMPTE170M;
break;
case colorspace_e::rec709:
// Rec. 709
avcodec_colorspace.primaries = AVCOL_PRI_BT709;
avcodec_colorspace.transfer_function = AVCOL_TRC_BT709;
avcodec_colorspace.matrix = AVCOL_SPC_BT709;
avcodec_colorspace.software_format = SWS_CS_ITU709;
break;
case colorspace_e::bt2020sdr:
// Rec. 2020
avcodec_colorspace.primaries = AVCOL_PRI_BT2020;
assert(sunshine_colorspace.bit_depth == 10);
avcodec_colorspace.transfer_function = AVCOL_TRC_BT2020_10;
avcodec_colorspace.matrix = AVCOL_SPC_BT2020_NCL;
avcodec_colorspace.software_format = SWS_CS_BT2020;
break;
case colorspace_e::bt2020:
// Rec. 2020 with ST 2084 perceptual quantizer
avcodec_colorspace.primaries = AVCOL_PRI_BT2020;
assert(sunshine_colorspace.bit_depth == 10);
avcodec_colorspace.transfer_function = AVCOL_TRC_SMPTE2084;
avcodec_colorspace.matrix = AVCOL_SPC_BT2020_NCL;
avcodec_colorspace.software_format = SWS_CS_BT2020;
break;
}
avcodec_colorspace.range = sunshine_colorspace.full_range ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
return avcodec_colorspace;
}
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:
Kr = 0.299;
Kb = 0.114;
break;
case colorspace_e::rec709:
default:
Kr = 0.2126;
Kb = 0.0722;
break;
case colorspace_e::bt2020:
case colorspace_e::bt2020sdr:
Kr = 0.2627;
Kb = 0.0593;
break;
}
double Kg = 1.0 - Kr - Kb;
double y_mult, y_add;
double uv_mult, uv_add;
// "8.3 Matrix coefficients" section of ITU-T H.273
if (colorspace.full_range) {
y_mult = (1 << colorspace.bit_depth) - 1;
y_add = 0;
uv_mult = (1 << colorspace.bit_depth) - 1;
uv_add = (1 << (colorspace.bit_depth - 1));
} else {
y_mult = (1 << (colorspace.bit_depth - 8)) * 219;
y_add = (1 << (colorspace.bit_depth - 8)) * 16;
uv_mult = (1 << (colorspace.bit_depth - 8)) * 224;
uv_add = (1 << (colorspace.bit_depth - 8)) * 128;
}
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;
color_vectors.color_vec_y[0] = Kr * y_mult;
color_vectors.color_vec_y[1] = Kg * y_mult;
color_vectors.color_vec_y[2] = Kb * y_mult;
color_vectors.color_vec_y[3] = y_add;
color_vectors.color_vec_u[0] = -0.5 * Kr / (1.0 - Kb) * uv_mult;
color_vectors.color_vec_u[1] = -0.5 * Kg / (1.0 - Kb) * uv_mult;
color_vectors.color_vec_u[2] = 0.5 * uv_mult;
color_vectors.color_vec_u[3] = uv_add;
color_vectors.color_vec_v[0] = 0.5 * uv_mult;
color_vectors.color_vec_v[1] = -0.5 * Kg / (1.0 - Kr) * uv_mult;
color_vectors.color_vec_v[2] = -0.5 * Kb / (1.0 - Kr) * uv_mult;
color_vectors.color_vec_v[3] = uv_add;
// Unused
color_vectors.range_y[0] = 1;
color_vectors.range_y[1] = 0;
color_vectors.range_uv[0] = 1;
color_vectors.range_uv[1] = 0;
return color_vectors;
};
static constexpr color_t colors[] = {
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;
switch (colorspace.colorspace) {
case colorspace_e::rec601:
result = &colors[0];
break;
case colorspace_e::rec709:
default:
result = &colors[4];
break;
case colorspace_e::bt2020:
case colorspace_e::bt2020sdr:
result = &colors[8];
break;
}
if (colorspace.bit_depth == 10) {
result += 2;
}
if (colorspace.full_range) {
result += 1;
}
if (unorm_output) {
result += 12;
}
return result;
}
} // namespace video