/*
* 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 <stdint.h>
#include <math.h>
#include <assert.h>
#include <libavutil/common.h>
#include <libavcodec/avcodec.h>
#include "csputils.h"
char * const mp_csp_names[MP_CSP_COUNT] = {
"Autoselect",
"BT.601 (SD)",
"BT.709 (HD)",
"SMPTE-240M",
"RGB",
"XYZ",
"YCgCo",
};
char * const mp_csp_equalizer_names[MP_CSP_EQ_COUNT] = {
"brightness",
"contrast",
"hue",
"saturation",
"gamma",
};
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;
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;
}
}
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;
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;
}
}
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_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;
}
}
// 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;
}
}
/* 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 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_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: {
static const float xyz_to_rgb[3][4] = {
{3.2404542, -1.5371385, -0.4985314},
{-0.9692660, 1.8760108, 0.0415560},
{0.0556434, -0.2040259, 1.0572252},
};
memcpy(m, xyz_to_rgb, sizeof(xyz_to_rgb));
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 m00 = in[0][0], m01 = in[0][1], m02 = in[0][2], m03 = in[0][3],
m10 = in[1][0], m11 = in[1][1], m12 = in[1][2], m13 = in[1][3],
m20 = in[2][0], m21 = in[2][1], m22 = in[2][2], m23 = in[2][3];
// calculate the adjoint
out[0][0] = (m11 * m22 - m21 * m12);
out[0][1] = -(m01 * m22 - m21 * m02);
out[0][2] = (m01 * m12 - m11 * m02);
out[1][0] = -(m10 * m22 - m20 * m12);
out[1][1] = (m00 * m22 - m20 * m02);
out[1][2] = -(m00 * m12 - m10 * m02);
out[2][0] = (m10 * m21 - m20 * m11);
out[2][1] = -(m00 * m21 - m20 * m01);
out[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 * out[0][0] + m10 * out[0][1] + m20 * out[0][2];
det = 1.0f / det;
out[0][0] *= det;
out[0][1] *= det;
out[0][2] *= det;
out[1][0] *= det;
out[1][1] *= det;
out[1][2] *= det;
out[2][0] *= det;
out[2][1] *= det;
out[2][2] *= det;
// 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] * m03 + out[0][1] * m13 + out[0][2] * m23);
out[1][3] = -(out[1][0] * m03 + out[1][1] * m13 + out[1][2] * m23);
out[2][3] = -(out[2][0] * m03 + out[2][1] * m13 + out[2][2] * m23);
}
// 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);
}
}