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|
/*
* Common code related to colorspaces and conversion
*
* Copyleft (C) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
*
* mp_invert_yuv2rgb based on DarkPlaces engine, original code (GPL2 or later)
*
* This file is part of MPlayer.
*
* MPlayer is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* MPlayer is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with MPlayer; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* You can alternatively redistribute this file and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*/
#include "config.h"
#include <stdint.h>
#include <math.h>
#include <assert.h>
#include <libavutil/common.h>
#include <libavcodec/avcodec.h>
#include "csputils.h"
const char *const mp_csp_names[MP_CSP_COUNT] = {
"Autoselect",
"BT.601 (SD)",
"BT.709 (HD)",
"SMPTE-240M",
"BT.2020-NCL (UHD)",
"BT.2020-CL (UHD)",
"RGB",
"XYZ",
"YCgCo",
};
const char *const mp_csp_levels_names[MP_CSP_LEVELS_COUNT] = {
"Autoselect",
"TV",
"PC",
};
const char *const mp_csp_prim_names[MP_CSP_PRIM_COUNT] = {
"Autoselect",
"BT.601 (525-line SD)",
"BT.601 (625-line SD)",
"BT.709 (HD)",
"BT.2020 (UHD)",
};
const char *const mp_csp_equalizer_names[MP_CSP_EQ_COUNT] = {
"brightness",
"contrast",
"hue",
"saturation",
"gamma",
};
const char *const mp_chroma_names[MP_CHROMA_COUNT] = {
"unknown",
"mpeg2/4/h264",
"mpeg1/jpeg",
};
// The short name _must_ match with what vf_stereo3d accepts (if supported).
// The long name is closer to the Matroska spec (StereoMode element).
// The numeric index matches the Matroska StereoMode value. If you add entries
// that don't match Matroska, make sure demux_mkv.c rejects them properly.
// The long name is unused.
#define E(index, short, long) [index] = short
const char *const mp_stereo3d_names[MP_STEREO3D_COUNT] = {
E(0, "mono", "mono"), // unsupported by vf_stereo3d
E(1, "sbs2l", "side_by_side_left"),
E(2, "ab2r", "top_bottom_right"),
E(3, "ab2l", "top_bottom_left"),
E(4, "checkr", "checkboard_right"), // unsupported by vf_stereo3d
E(5, "checkl", "checkboard_left"), // unsupported by vf_stereo3d
E(6, "irr", "row_interleaved_right"),
E(7, "irl", "row_interleaved_left"),
E(8, "icr", "column_interleaved_right"),// unsupported by vf_stereo3d
E(9, "icl", "column_interleaved_left"), // unsupported by vf_stereo3d
E(10, "arcc", "anaglyph_cyan_red"), // Matroska: unclear which mode
E(11, "sbs2r", "side_by_side_right"),
E(12, "agmc", "anaglyph_green_magenta"), // Matroska: unclear which mode
};
enum mp_csp avcol_spc_to_mp_csp(int avcolorspace)
{
switch (avcolorspace) {
case AVCOL_SPC_BT709: return MP_CSP_BT_709;
case AVCOL_SPC_BT470BG: return MP_CSP_BT_601;
#if HAVE_AVCOL_SPC_BT2020
case AVCOL_SPC_BT2020_NCL: return MP_CSP_BT_2020_NC;
case AVCOL_SPC_BT2020_CL: return MP_CSP_BT_2020_C;
#endif
case AVCOL_SPC_SMPTE170M: return MP_CSP_BT_601;
case AVCOL_SPC_SMPTE240M: return MP_CSP_SMPTE_240M;
case AVCOL_SPC_RGB: return MP_CSP_RGB;
case AVCOL_SPC_YCOCG: return MP_CSP_YCGCO;
default: return MP_CSP_AUTO;
}
}
enum mp_csp_levels avcol_range_to_mp_csp_levels(int avrange)
{
switch (avrange) {
case AVCOL_RANGE_MPEG: return MP_CSP_LEVELS_TV;
case AVCOL_RANGE_JPEG: return MP_CSP_LEVELS_PC;
default: return MP_CSP_LEVELS_AUTO;
}
}
enum mp_csp_prim avcol_pri_to_mp_csp_prim(int avpri)
{
switch (avpri) {
case AVCOL_PRI_SMPTE240M: // Same as below
case AVCOL_PRI_SMPTE170M: return MP_CSP_PRIM_BT_601_525;
case AVCOL_PRI_BT470BG: return MP_CSP_PRIM_BT_601_625;
case AVCOL_PRI_BT709: return MP_CSP_PRIM_BT_709;
#if HAVE_AVCOL_SPC_BT2020
case AVCOL_PRI_BT2020: return MP_CSP_PRIM_BT_2020;
#endif
default: return MP_CSP_PRIM_AUTO;
}
}
int mp_csp_to_avcol_spc(enum mp_csp colorspace)
{
switch (colorspace) {
case MP_CSP_BT_709: return AVCOL_SPC_BT709;
case MP_CSP_BT_601: return AVCOL_SPC_BT470BG;
#if HAVE_AVCOL_SPC_BT2020
case MP_CSP_BT_2020_NC: return AVCOL_SPC_BT2020_NCL;
case MP_CSP_BT_2020_C: return AVCOL_SPC_BT2020_CL;
#endif
case MP_CSP_SMPTE_240M: return AVCOL_SPC_SMPTE240M;
case MP_CSP_RGB: return AVCOL_SPC_RGB;
case MP_CSP_YCGCO: return AVCOL_SPC_YCOCG;
default: return AVCOL_SPC_UNSPECIFIED;
}
}
int mp_csp_levels_to_avcol_range(enum mp_csp_levels range)
{
switch (range) {
case MP_CSP_LEVELS_TV: return AVCOL_RANGE_MPEG;
case MP_CSP_LEVELS_PC: return AVCOL_RANGE_JPEG;
default: return AVCOL_RANGE_UNSPECIFIED;
}
}
int mp_csp_prim_to_avcol_pri(enum mp_csp_prim prim)
{
switch (prim) {
case MP_CSP_PRIM_BT_601_525: return AVCOL_PRI_SMPTE170M;
case MP_CSP_PRIM_BT_601_625: return AVCOL_PRI_BT470BG;
case MP_CSP_PRIM_BT_709: return AVCOL_PRI_BT709;
#if HAVE_AVCOL_SPC_BT2020
case MP_CSP_PRIM_BT_2020: return AVCOL_PRI_BT2020;
#endif
default: return AVCOL_PRI_UNSPECIFIED;
}
}
enum mp_csp mp_csp_guess_colorspace(int width, int height)
{
return width >= 1280 || height > 576 ? MP_CSP_BT_709 : MP_CSP_BT_601;
}
enum mp_csp_prim mp_csp_guess_primaries(int width, int height)
{
// HD content
if (width >= 1280 || height > 576)
return MP_CSP_PRIM_BT_709;
switch (height) {
case 576: // Typical PAL content, including anamorphic/squared
return MP_CSP_PRIM_BT_601_625;
case 480: // Typical NTSC content, including squared
case 486: // NTSC Pro or anamorphic NTSC
return MP_CSP_PRIM_BT_601_525;
default: // No good metric, just pick BT.709 to minimize damage
return MP_CSP_PRIM_BT_709;
}
}
enum mp_chroma_location avchroma_location_to_mp(int avloc)
{
switch (avloc) {
case AVCHROMA_LOC_LEFT: return MP_CHROMA_LEFT;
case AVCHROMA_LOC_CENTER: return MP_CHROMA_CENTER;
default: return MP_CHROMA_AUTO;
}
}
int mp_chroma_location_to_av(enum mp_chroma_location mploc)
{
switch (mploc) {
case MP_CHROMA_LEFT: return AVCHROMA_LOC_LEFT;
case MP_CHROMA_CENTER: return AVCHROMA_LOC_CENTER;
default: return AVCHROMA_LOC_UNSPECIFIED;
}
}
// Return location of chroma samples relative to luma samples. 0/0 means
// centered. Other possible values are -1 (top/left) and +1 (right/bottom).
void mp_get_chroma_location(enum mp_chroma_location loc, int *x, int *y)
{
*x = 0;
*y = 0;
if (loc == MP_CHROMA_LEFT)
*x = -1;
}
/**
* \brief little helper function to create a lookup table for gamma
* \param map buffer to create map into
* \param size size of buffer
* \param gamma gamma value
*/
void mp_gen_gamma_map(uint8_t *map, int size, float gamma)
{
if (gamma == 1.0) {
for (int i = 0; i < size; i++)
map[i] = 255 * i / (size - 1);
return;
}
gamma = 1.0 / gamma;
for (int i = 0; i < size; i++) {
float tmp = (float)i / (size - 1.0);
tmp = pow(tmp, gamma);
if (tmp > 1.0)
tmp = 1.0;
if (tmp < 0.0)
tmp = 0.0;
map[i] = 255 * tmp;
}
}
void mp_invert_matrix3x3(float m[3][3])
{
float m00 = m[0][0], m01 = m[0][1], m02 = m[0][2],
m10 = m[1][0], m11 = m[1][1], m12 = m[1][2],
m20 = m[2][0], m21 = m[2][1], m22 = m[2][2];
// calculate the adjoint
m[0][0] = (m11 * m22 - m21 * m12);
m[0][1] = -(m01 * m22 - m21 * m02);
m[0][2] = (m01 * m12 - m11 * m02);
m[1][0] = -(m10 * m22 - m20 * m12);
m[1][1] = (m00 * m22 - m20 * m02);
m[1][2] = -(m00 * m12 - m10 * m02);
m[2][0] = (m10 * m21 - m20 * m11);
m[2][1] = -(m00 * m21 - m20 * m01);
m[2][2] = (m00 * m11 - m10 * m01);
// calculate the determinant (as inverse == 1/det * adjoint,
// adjoint * m == identity * det, so this calculates the det)
float det = m00 * m[0][0] + m10 * m[0][1] + m20 * m[0][2];
det = 1.0f / det;
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++)
m[i][j] *= det;
}
}
// A := A * B
void mp_mul_matrix3x3(float a[3][3], float b[3][3])
{
float a00 = a[0][0], a01 = a[0][1], a02 = a[0][2],
a10 = a[1][0], a11 = a[1][1], a12 = a[1][2],
a20 = a[2][0], a21 = a[2][1], a22 = a[2][2];
for (int i = 0; i < 3; i++) {
a[0][i] = a00 * b[0][i] + a01 * b[1][i] + a02 * b[2][i];
a[1][i] = a10 * b[0][i] + a11 * b[1][i] + a12 * b[2][i];
a[2][i] = a20 * b[0][i] + a21 * b[1][i] + a22 * b[2][i];
}
}
/**
* \brief return the primaries associated with a certain mp_csp_primaries val
* \param csp the colorspace for which to return the primaries
*/
struct mp_csp_primaries mp_get_csp_primaries(enum mp_csp_prim spc)
{
/*
Values from: ITU-R Recommendations BT.601-7, BT.709-5, BT.2020-0
https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.601-7-201103-I!!PDF-E.pdf
https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.709-5-200204-I!!PDF-E.pdf
https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.2020-0-201208-I!!PDF-E.pdf
*/
static const struct mp_csp_col_xy d65 = {0.3127, 0.3290};
switch (spc) {
case MP_CSP_PRIM_BT_601_525:
return (struct mp_csp_primaries) {
.red = {0.630, 0.340},
.green = {0.310, 0.595},
.blue = {0.155, 0.070},
.white = d65
};
case MP_CSP_PRIM_BT_601_625:
return (struct mp_csp_primaries) {
.red = {0.640, 0.330},
.green = {0.290, 0.600},
.blue = {0.150, 0.060},
.white = d65
};
// This is the default assumption if no colorspace information could
// be determined, eg. for files which have no video channel.
case MP_CSP_PRIM_AUTO:
case MP_CSP_PRIM_BT_709:
return (struct mp_csp_primaries) {
.red = {0.640, 0.330},
.green = {0.300, 0.600},
.blue = {0.150, 0.060},
.white = d65
};
case MP_CSP_PRIM_BT_2020:
return (struct mp_csp_primaries) {
.red = {0.708, 0.292},
.green = {0.170, 0.797},
.blue = {0.131, 0.046},
.white = d65
};
default:
return (struct mp_csp_primaries) {{0}};
}
}
// Compute the RGB/XYZ matrix as described here:
// http://www.brucelindbloom.com/index.html?Eqn_RGB_XYZ_Matrix.html
void mp_get_rgb2xyz_matrix(struct mp_csp_primaries space, float m[3][3])
{
float S[3], X[4], Z[4];
// Convert from CIE xyY to XYZ. Note that Y=1 holds true for all primaries
X[0] = space.red.x / space.red.y;
X[1] = space.green.x / space.green.y;
X[2] = space.blue.x / space.blue.y;
X[3] = space.white.x / space.white.y;
Z[0] = (1 - space.red.x - space.red.y) / space.red.y;
Z[1] = (1 - space.green.x - space.green.y) / space.green.y;
Z[2] = (1 - space.blue.x - space.blue.y) / space.blue.y;
Z[3] = (1 - space.white.x - space.white.y) / space.white.y;
// S = XYZ^-1 * W
for (int i = 0; i < 3; i++) {
m[0][i] = X[i];
m[1][i] = 1;
m[2][i] = Z[i];
}
mp_invert_matrix3x3(m);
for (int i = 0; i < 3; i++)
S[i] = m[i][0] * X[3] + m[i][1] * 1 + m[i][2] * Z[3];
// M = [Sc * XYZc]
for (int i = 0; i < 3; i++) {
m[0][i] = S[i] * X[i];
m[1][i] = S[i] * 1;
m[2][i] = S[i] * Z[i];
}
}
// M := M * XYZd<-XYZs
void mp_apply_chromatic_adaptation(struct mp_csp_col_xy src, struct mp_csp_col_xy dest, float m[3][3])
{
// If the white points are nearly identical, this is a wasteful identity
// operation.
if (fabs(src.x - dest.x) < 1e-6 && fabs(src.y - dest.y) < 1e-6)
return;
// XYZd<-XYZs = Ma^-1 * (I*[Cd/Cs]) * Ma
// http://www.brucelindbloom.com/index.html?Eqn_ChromAdapt.html
float C[3][2], tmp[3][3] = {{0}};
// Ma = Bradford matrix, arguably most popular method in use today.
// This is derived experimentally and thus hard-coded.
float bradford[3][3] = {
{ 0.8951, 0.2664, -0.1614 },
{ -0.7502, 1.7135, 0.0367 },
{ 0.0389, -0.0685, 1.0296 },
};
for (int i = 0; i < 3; i++) {
// source cone
C[i][0] = bradford[i][0] * src.x / src.y
+ bradford[i][1] * 1
+ bradford[i][2] * (1 - src.x - src.y) / src.y;
// dest cone
C[i][1] = bradford[i][0] * dest.x / dest.y
+ bradford[i][1] * 1
+ bradford[i][2] * (1 - dest.x - dest.y) / dest.y;
}
// tmp := I * [Cd/Cs] * Ma
for (int i = 0; i < 3; i++)
tmp[i][i] = C[i][1] / C[i][0];
mp_mul_matrix3x3(tmp, bradford);
// M := M * Ma^-1 * tmp
mp_invert_matrix3x3(bradford);
mp_mul_matrix3x3(m, bradford);
mp_mul_matrix3x3(m, tmp);
}
/**
* \brief get the coefficients of the source -> bt2020 cms matrix
* \param src primaries of the source gamut
* \param dest primaries of the destination gamut
* \param intent rendering intent for the transformation
* \param m array to store coefficients into
*/
void mp_get_cms_matrix(struct mp_csp_primaries src, struct mp_csp_primaries dest, enum mp_render_intent intent, float m[3][3])
{
float tmp[3][3];
// In saturation mapping, we don't care about accuracy and just want
// primaries to map to primaries, making this an identity transformation.
if (intent == MP_INTENT_SATURATION) {
for (int i = 0; i < 3; i++)
m[i][i] = 1;
return;
}
// RGBd<-RGBs = RGBd<-XYZd * XYZd<-XYZs * XYZs<-RGBs
// Equations from: http://www.brucelindbloom.com/index.html?Math.html
// Note: Perceptual is treated like relative colorimetric. There's no
// definition for perceptual other than "make it look good".
// RGBd<-XYZd, inverted from XYZd<-RGBd
mp_get_rgb2xyz_matrix(dest, m);
mp_invert_matrix3x3(m);
// Chromatic adaptation, except in absolute colorimetric intent
if (intent != MP_INTENT_ABSOLUTE_COLORIMETRIC)
mp_apply_chromatic_adaptation(src.white, dest.white, m);
// XYZs<-RGBs
mp_get_rgb2xyz_matrix(src, tmp);
mp_mul_matrix3x3(m, tmp);
}
/* Fill in the Y, U, V vectors of a yuv2rgb conversion matrix
* based on the given luma weights of the R, G and B components (lr, lg, lb).
* lr+lg+lb is assumed to equal 1.
* This function is meant for colorspaces satisfying the following
* conditions (which are true for common YUV colorspaces):
* - The mapping from input [Y, U, V] to output [R, G, B] is linear.
* - Y is the vector [1, 1, 1]. (meaning input Y component maps to 1R+1G+1B)
* - U maps to a value with zero R and positive B ([0, x, y], y > 0;
* i.e. blue and green only).
* - V maps to a value with zero B and positive R ([x, y, 0], x > 0;
* i.e. red and green only).
* - U and V are orthogonal to the luma vector [lr, lg, lb].
* - The magnitudes of the vectors U and V are the minimal ones for which
* the image of the set Y=[0...1],U=[-0.5...0.5],V=[-0.5...0.5] under the
* conversion function will cover the set R=[0...1],G=[0...1],B=[0...1]
* (the resulting matrix can be converted for other input/output ranges
* outside this function).
* Under these conditions the given parameters lr, lg, lb uniquely
* determine the mapping of Y, U, V to R, G, B.
*/
static void luma_coeffs(float m[3][4], float lr, float lg, float lb)
{
assert(fabs(lr+lg+lb - 1) < 1e-6);
m[0][0] = m[1][0] = m[2][0] = 1;
m[0][1] = 0;
m[1][1] = -2 * (1-lb) * lb/lg;
m[2][1] = 2 * (1-lb);
m[0][2] = 2 * (1-lr);
m[1][2] = -2 * (1-lr) * lr/lg;
m[2][2] = 0;
// Constant coefficients (m[x][3]) not set here
}
/**
* \brief get the coefficients of an SMPTE 428-1 xyz -> rgb conversion matrix
* \param params parameters for the conversion, only brightness is used
* \param prim primaries of the RGB space to transform to
* \param intent the rendering intent used to convert to the target primaries
* \param m array to store the coefficients into
*/
void mp_get_xyz2rgb_coeffs(struct mp_csp_params *params, struct mp_csp_primaries prim, enum mp_render_intent intent, float m[3][4])
{
float tmp[3][3], brightness = params->brightness;
mp_get_rgb2xyz_matrix(prim, tmp);
mp_invert_matrix3x3(tmp);
// All non-absolute mappings want to map source white to target white
if (intent != MP_INTENT_ABSOLUTE_COLORIMETRIC) {
// SMPTE 428-1 defines the calibration white point as CIE xy (0.314, 0.351)
static const struct mp_csp_col_xy smpte428 = {0.314, 0.351};
mp_apply_chromatic_adaptation(smpte428, prim.white, tmp);
}
// Since this outputs linear RGB rather than companded RGB, we
// want to linearize any brightness additions. 2 is a reasonable
// approximation for any sort of gamma function that could be in use.
// As this is an aesthetic setting only, any exact values do not matter.
if (brightness < 0) {
brightness *= -brightness;
} else {
brightness *= brightness;
}
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++)
m[i][j] = tmp[i][j];
m[i][COL_C] = brightness;
}
}
/**
* \brief get the coefficients of the yuv -> rgb conversion matrix
* \param params struct specifying the properties of the conversion like
* brightness, ...
* \param m array to store coefficients into
*/
void mp_get_yuv2rgb_coeffs(struct mp_csp_params *params, float m[3][4])
{
int format = params->colorspace.format;
if (format <= MP_CSP_AUTO || format >= MP_CSP_COUNT)
format = MP_CSP_BT_601;
int levels_in = params->colorspace.levels_in;
if (levels_in <= MP_CSP_LEVELS_AUTO || levels_in >= MP_CSP_LEVELS_COUNT)
levels_in = MP_CSP_LEVELS_TV;
switch (format) {
case MP_CSP_BT_601: luma_coeffs(m, 0.299, 0.587, 0.114 ); break;
case MP_CSP_BT_709: luma_coeffs(m, 0.2126, 0.7152, 0.0722); break;
case MP_CSP_SMPTE_240M: luma_coeffs(m, 0.2122, 0.7013, 0.0865); break;
case MP_CSP_BT_2020_NC: luma_coeffs(m, 0.2627, 0.6780, 0.0593); break;
case MP_CSP_BT_2020_C: {
// Note: This outputs into the [-0.5,0.5] range for chroma information.
// If this clips on any VO, a constant 0.5 coefficient can be added
// to the chroma channels to normalize them into [0,1]. This is not
// currently needed by anything, though.
static const float ycbcr_to_crycb[3][4] = {{0, 0, 1}, {1, 0, 0}, {0, 1, 0}};
memcpy(m, ycbcr_to_crycb, sizeof(ycbcr_to_crycb));
break;
}
case MP_CSP_RGB: {
static const float ident[3][4] = {{1, 0, 0}, {0, 1, 0}, {0, 0, 1}};
memcpy(m, ident, sizeof(ident));
levels_in = -1;
break;
}
case MP_CSP_XYZ: {
// The vo should probably not be using a matrix generated by this
// function for XYZ sources, but if it does, let's just assume it
// wants BT.709 with D65 white point (virtually all other content).
mp_get_xyz2rgb_coeffs(params, mp_get_csp_primaries(MP_CSP_PRIM_BT_709),
MP_INTENT_RELATIVE_COLORIMETRIC, m);
levels_in = -1;
break;
}
case MP_CSP_YCGCO: {
static const float ycgco_to_rgb[3][4] = {
{1, -1, 1},
{1, 1, 0},
{1, -1, -1},
};
memcpy(m, ycgco_to_rgb, sizeof(ycgco_to_rgb));
break;
}
default:
abort();
};
// Hue is equivalent to rotating input [U, V] subvector around the origin.
// Saturation scales [U, V].
float huecos = params->saturation * cos(params->hue);
float huesin = params->saturation * sin(params->hue);
for (int i = 0; i < 3; i++) {
float u = m[i][COL_U];
m[i][COL_U] = huecos * u - huesin * m[i][COL_V];
m[i][COL_V] = huesin * u + huecos * m[i][COL_V];
}
assert(params->input_bits >= 8);
assert(params->texture_bits >= params->input_bits);
double s = (1 << (params->input_bits-8)) / ((1<<params->texture_bits)-1.);
// The values below are written in 0-255 scale
struct yuvlevels { double ymin, ymax, cmin, cmid; }
yuvlim = { 16*s, 235*s, 16*s, 128*s },
yuvfull = { 0*s, 255*s, 1*s, 128*s }, // '1' for symmetry around 128
anyfull = { 0*s, 255*s, -255*s/2, 0 },
yuvlev;
switch (levels_in) {
case MP_CSP_LEVELS_TV: yuvlev = yuvlim; break;
case MP_CSP_LEVELS_PC: yuvlev = yuvfull; break;
case -1: yuvlev = anyfull; break;
default:
abort();
}
int levels_out = params->colorspace.levels_out;
if (levels_out <= MP_CSP_LEVELS_AUTO || levels_out >= MP_CSP_LEVELS_COUNT)
levels_out = MP_CSP_LEVELS_PC;
struct rgblevels { double min, max; }
rgblim = { 16/255., 235/255. },
rgbfull = { 0, 1 },
rgblev;
switch (levels_out) {
case MP_CSP_LEVELS_TV: rgblev = rgblim; break;
case MP_CSP_LEVELS_PC: rgblev = rgbfull; break;
default:
abort();
}
double ymul = (rgblev.max - rgblev.min) / (yuvlev.ymax - yuvlev.ymin);
double cmul = (rgblev.max - rgblev.min) / (yuvlev.cmid - yuvlev.cmin) / 2;
for (int i = 0; i < 3; i++) {
m[i][COL_Y] *= ymul;
m[i][COL_U] *= cmul;
m[i][COL_V] *= cmul;
// Set COL_C so that Y=umin,UV=cmid maps to RGB=min (black to black)
m[i][COL_C] = rgblev.min - m[i][COL_Y] * yuvlev.ymin
-(m[i][COL_U] + m[i][COL_V]) * yuvlev.cmid;
}
// Brightness adds a constant to output R,G,B.
// Contrast scales Y around 1/2 (not 0 in this implementation).
for (int i = 0; i < 3; i++) {
m[i][COL_C] += params->brightness;
m[i][COL_Y] *= params->contrast;
m[i][COL_C] += (rgblev.max-rgblev.min) * (1 - params->contrast)/2;
}
int in_bits = FFMAX(params->int_bits_in, 1);
int out_bits = FFMAX(params->int_bits_out, 1);
double in_scale = (1 << in_bits) - 1.0;
double out_scale = (1 << out_bits) - 1.0;
for (int i = 0; i < 3; i++) {
m[i][COL_C] *= out_scale; // constant is 1.0
for (int x = 0; x < 3; x++)
m[i][x] *= out_scale / in_scale;
}
}
//! size of gamma map use to avoid slow exp function in gen_yuv2rgb_map
#define GMAP_SIZE (1024)
/**
* \brief generate a 3D YUV -> RGB map
* \param params struct containing parameters like brightness, gamma, ...
* \param map where to store map. Must provide space for (size + 2)^3 elements
* \param size size of the map, excluding border
*/
void mp_gen_yuv2rgb_map(struct mp_csp_params *params, unsigned char *map, int size)
{
int i, j, k, l;
float step = 1.0 / size;
float y, u, v;
float yuv2rgb[3][4];
unsigned char gmaps[3][GMAP_SIZE];
mp_gen_gamma_map(gmaps[0], GMAP_SIZE, params->rgamma);
mp_gen_gamma_map(gmaps[1], GMAP_SIZE, params->ggamma);
mp_gen_gamma_map(gmaps[2], GMAP_SIZE, params->bgamma);
mp_get_yuv2rgb_coeffs(params, yuv2rgb);
for (i = 0; i < 3; i++)
for (j = 0; j < 4; j++)
yuv2rgb[i][j] *= GMAP_SIZE - 1;
v = 0;
for (i = -1; i <= size; i++) {
u = 0;
for (j = -1; j <= size; j++) {
y = 0;
for (k = -1; k <= size; k++) {
for (l = 0; l < 3; l++) {
float rgb = yuv2rgb[l][COL_Y] * y + yuv2rgb[l][COL_U] * u +
yuv2rgb[l][COL_V] * v + yuv2rgb[l][COL_C];
*map++ = gmaps[l][av_clip(rgb, 0, GMAP_SIZE - 1)];
}
y += (k == -1 || k == size - 1) ? step / 2 : step;
}
u += (j == -1 || j == size - 1) ? step / 2 : step;
}
v += (i == -1 || i == size - 1) ? step / 2 : step;
}
}
// Copy settings from eq into params.
void mp_csp_copy_equalizer_values(struct mp_csp_params *params,
const struct mp_csp_equalizer *eq)
{
params->brightness = eq->values[MP_CSP_EQ_BRIGHTNESS] / 100.0;
params->contrast = (eq->values[MP_CSP_EQ_CONTRAST] + 100) / 100.0;
params->hue = eq->values[MP_CSP_EQ_HUE] / 100.0 * 3.1415927;
params->saturation = (eq->values[MP_CSP_EQ_SATURATION] + 100) / 100.0;
float gamma = exp(log(8.0) * eq->values[MP_CSP_EQ_GAMMA] / 100.0);
params->rgamma = gamma;
params->ggamma = gamma;
params->bgamma = gamma;
}
static int find_eq(int capabilities, const char *name)
{
for (int i = 0; i < MP_CSP_EQ_COUNT; i++) {
if (strcmp(name, mp_csp_equalizer_names[i]) == 0)
return ((1 << i) & capabilities) ? i : -1;
}
return -1;
}
int mp_csp_equalizer_get(struct mp_csp_equalizer *eq, const char *property,
int *out_value)
{
int index = find_eq(eq->capabilities, property);
if (index < 0)
return -1;
*out_value = eq->values[index];
return 0;
}
int mp_csp_equalizer_set(struct mp_csp_equalizer *eq, const char *property,
int value)
{
int index = find_eq(eq->capabilities, property);
if (index < 0)
return 0;
eq->values[index] = value;
return 1;
}
void mp_invert_yuv2rgb(float out[3][4], float in[3][4])
{
float tmp[3][3];
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++)
tmp[i][j] = in[i][j];
}
mp_invert_matrix3x3(tmp);
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++)
out[i][j] = tmp[i][j];
}
// fix the constant coefficient
// rgb = M * yuv + C
// M^-1 * rgb = yuv + M^-1 * C
// yuv = M^-1 * rgb - M^-1 * C
// ^^^^^^^^^^
out[0][3] = -(out[0][0] * in[0][3] + out[0][1] * in[1][3] + out[0][2] * in[2][3]);
out[1][3] = -(out[1][0] * in[0][3] + out[1][1] * in[1][3] + out[1][2] * in[2][3]);
out[2][3] = -(out[2][0] * in[0][3] + out[2][1] * in[1][3] + out[2][2] * in[2][3]);
}
// Multiply the color in c with the given matrix.
// c is {R, G, B} or {Y, U, V} (depending on input/output and matrix).
// Output is clipped to the given number of bits.
void mp_map_int_color(float matrix[3][4], int clip_bits, int c[3])
{
int in[3] = {c[0], c[1], c[2]};
for (int i = 0; i < 3; i++) {
double val = matrix[i][3];
for (int x = 0; x < 3; x++)
val += matrix[i][x] * in[x];
int ival = lrint(val);
c[i] = av_clip(ival, 0, (1 << clip_bits) - 1);
}
}
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