mpv/video/csputils.c

855 lines
30 KiB
C

/*
* Common code related to colorspaces and conversion
*
* Copyleft (C) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
*
* mp_invert_cmat based on DarkPlaces engine, original code (GPL2 or later)
*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it 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.
*
* mpv 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <stdint.h>
#include <math.h>
#include <assert.h>
#include <libavutil/common.h>
#include <libavcodec/avcodec.h>
#include "mp_image.h"
#include "csputils.h"
#include "options/m_option.h"
const struct m_opt_choice_alternatives mp_csp_names[] = {
{"auto", MP_CSP_AUTO},
{"bt.601", MP_CSP_BT_601},
{"bt.709", MP_CSP_BT_709},
{"smpte-240m", MP_CSP_SMPTE_240M},
{"bt.2020-ncl", MP_CSP_BT_2020_NC},
{"bt.2020-cl", MP_CSP_BT_2020_C},
{"rgb", MP_CSP_RGB},
{"xyz", MP_CSP_XYZ},
{"ycgco", MP_CSP_YCGCO},
{0}
};
const struct m_opt_choice_alternatives mp_csp_levels_names[] = {
{"auto", MP_CSP_LEVELS_AUTO},
{"limited", MP_CSP_LEVELS_TV},
{"full", MP_CSP_LEVELS_PC},
{0}
};
const struct m_opt_choice_alternatives mp_csp_prim_names[] = {
{"auto", MP_CSP_PRIM_AUTO},
{"bt.601-525", MP_CSP_PRIM_BT_601_525},
{"bt.601-625", MP_CSP_PRIM_BT_601_625},
{"bt.709", MP_CSP_PRIM_BT_709},
{"bt.2020", MP_CSP_PRIM_BT_2020},
{"bt.470m", MP_CSP_PRIM_BT_470M},
{"apple", MP_CSP_PRIM_APPLE},
{"adobe", MP_CSP_PRIM_ADOBE},
{"prophoto", MP_CSP_PRIM_PRO_PHOTO},
{"cie1931", MP_CSP_PRIM_CIE_1931},
{"dci-p3", MP_CSP_PRIM_DCI_P3},
{"v-gamut", MP_CSP_PRIM_V_GAMUT},
{0}
};
const struct m_opt_choice_alternatives mp_csp_trc_names[] = {
{"auto", MP_CSP_TRC_AUTO},
{"bt.1886", MP_CSP_TRC_BT_1886},
{"srgb", MP_CSP_TRC_SRGB},
{"linear", MP_CSP_TRC_LINEAR},
{"gamma1.8", MP_CSP_TRC_GAMMA18},
{"gamma2.2", MP_CSP_TRC_GAMMA22},
{"gamma2.8", MP_CSP_TRC_GAMMA28},
{"prophoto", MP_CSP_TRC_PRO_PHOTO},
{"st2084", MP_CSP_TRC_SMPTE_ST2084},
{"std-b67", MP_CSP_TRC_ARIB_STD_B67},
{"v-log", MP_CSP_TRC_V_LOG},
{0}
};
const char *const mp_csp_equalizer_names[MP_CSP_EQ_COUNT] = {
"brightness",
"contrast",
"hue",
"saturation",
"gamma",
"output-levels",
};
const struct m_opt_choice_alternatives mp_chroma_names[] = {
{"unknown", MP_CHROMA_AUTO},
{"mpeg2/4/h264",MP_CHROMA_LEFT},
{"mpeg1/jpeg", MP_CHROMA_CENTER},
{0}
};
// The short name _must_ match with what vf_stereo3d accepts (if supported).
// The long name in comments 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.
const struct m_opt_choice_alternatives mp_stereo3d_names[] = {
{"no", -1}, // disable/invalid
{"mono", 0},
{"sbs2l", 1}, // "side_by_side_left"
{"ab2r", 2}, // "top_bottom_right"
{"ab2l", 3}, // "top_bottom_left"
{"checkr", 4}, // "checkboard_right" (unsupported by vf_stereo3d)
{"checkl", 5}, // "checkboard_left" (unsupported by vf_stereo3d)
{"irr", 6}, // "row_interleaved_right"
{"irl", 7}, // "row_interleaved_left"
{"icr", 8}, // "column_interleaved_right" (unsupported by vf_stereo3d)
{"icl", 9}, // "column_interleaved_left" (unsupported by vf_stereo3d)
{"arcc", 10}, // "anaglyph_cyan_red" (Matroska: unclear which mode)
{"sbs2r", 11}, // "side_by_side_right"
{"agmc", 12}, // "anaglyph_green_magenta" (Matroska: unclear which mode)
{"al", 13}, // "alternating frames left first"
{"ar", 14}, // "alternating frames right first"
{0}
};
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_BT2020_NCL: return MP_CSP_BT_2020_NC;
case AVCOL_SPC_BT2020_CL: return MP_CSP_BT_2020_C;
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;
case AVCOL_PRI_BT2020: return MP_CSP_PRIM_BT_2020;
case AVCOL_PRI_BT470M: return MP_CSP_PRIM_BT_470M;
default: return MP_CSP_PRIM_AUTO;
}
}
enum mp_csp_trc avcol_trc_to_mp_csp_trc(int avtrc)
{
switch (avtrc) {
case AVCOL_TRC_BT709:
case AVCOL_TRC_SMPTE170M:
case AVCOL_TRC_SMPTE240M:
case AVCOL_TRC_BT1361_ECG:
case AVCOL_TRC_BT2020_10:
case AVCOL_TRC_BT2020_12: return MP_CSP_TRC_BT_1886;
case AVCOL_TRC_IEC61966_2_1: return MP_CSP_TRC_SRGB;
case AVCOL_TRC_LINEAR: return MP_CSP_TRC_LINEAR;
case AVCOL_TRC_GAMMA22: return MP_CSP_TRC_GAMMA22;
case AVCOL_TRC_GAMMA28: return MP_CSP_TRC_GAMMA28;
#if HAVE_AVUTIL_HDR
case AVCOL_TRC_SMPTEST2084: return MP_CSP_TRC_SMPTE_ST2084;
case AVCOL_TRC_ARIB_STD_B67: return MP_CSP_TRC_ARIB_STD_B67;
#endif
default: return MP_CSP_TRC_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_BT_2020_NC: return AVCOL_SPC_BT2020_NCL;
case MP_CSP_BT_2020_C: return AVCOL_SPC_BT2020_CL;
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;
case MP_CSP_PRIM_BT_2020: return AVCOL_PRI_BT2020;
case MP_CSP_PRIM_BT_470M: return AVCOL_PRI_BT470M;
default: return AVCOL_PRI_UNSPECIFIED;
}
}
int mp_csp_trc_to_avcol_trc(enum mp_csp_trc trc)
{
switch (trc) {
// We just call it BT.1886 since we're decoding, but it's still BT.709
case MP_CSP_TRC_BT_1886: return AVCOL_TRC_BT709;
case MP_CSP_TRC_SRGB: return AVCOL_TRC_IEC61966_2_1;
case MP_CSP_TRC_LINEAR: return AVCOL_TRC_LINEAR;
case MP_CSP_TRC_GAMMA22: return AVCOL_TRC_GAMMA22;
case MP_CSP_TRC_GAMMA28: return AVCOL_TRC_GAMMA28;
#if HAVE_AVUTIL_HDR
case MP_CSP_TRC_SMPTE_ST2084: return AVCOL_TRC_SMPTEST2084;
case MP_CSP_TRC_ARIB_STD_B67: return AVCOL_TRC_ARIB_STD_B67;
#endif
default: return AVCOL_TRC_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;
}
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
static 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];
}
}
// return the primaries associated with a certain mp_csp_primaries val
struct mp_csp_primaries mp_get_csp_primaries(enum mp_csp_prim spc)
{
/*
Values from: ITU-R Recommendations BT.470-6, BT.601-7, BT.709-5, BT.2020-0
https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.470-6-199811-S!!PDF-E.pdf
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
Other colorspaces from https://en.wikipedia.org/wiki/RGB_color_space#Specifications
*/
// CIE standard illuminant series
static const struct mp_csp_col_xy
d50 = {0.34577, 0.35850},
d65 = {0.31271, 0.32902},
c = {0.31006, 0.31616},
e = {1.0/3.0, 1.0/3.0};
switch (spc) {
case MP_CSP_PRIM_BT_470M:
return (struct mp_csp_primaries) {
.red = {0.670, 0.330},
.green = {0.210, 0.710},
.blue = {0.140, 0.080},
.white = c
};
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
};
case MP_CSP_PRIM_APPLE:
return (struct mp_csp_primaries) {
.red = {0.625, 0.340},
.green = {0.280, 0.595},
.blue = {0.115, 0.070},
.white = d65
};
case MP_CSP_PRIM_ADOBE:
return (struct mp_csp_primaries) {
.red = {0.640, 0.330},
.green = {0.210, 0.710},
.blue = {0.150, 0.060},
.white = d65
};
case MP_CSP_PRIM_PRO_PHOTO:
return (struct mp_csp_primaries) {
.red = {0.7347, 0.2653},
.green = {0.1596, 0.8404},
.blue = {0.0366, 0.0001},
.white = d50
};
case MP_CSP_PRIM_CIE_1931:
return (struct mp_csp_primaries) {
.red = {0.7347, 0.2653},
.green = {0.2738, 0.7174},
.blue = {0.1666, 0.0089},
.white = e
};
// From SMPTE RP 431-2
case MP_CSP_PRIM_DCI_P3:
return (struct mp_csp_primaries) {
.red = {0.680, 0.320},
.green = {0.265, 0.690},
.blue = {0.150, 0.060},
.white = d65
};
// From Panasonic VARICAM reference manual
case MP_CSP_PRIM_V_GAMUT:
return (struct mp_csp_primaries) {
.red = {0.730, 0.280},
.green = {0.165, 0.840},
.blue = {0.100, -0.03},
.white = d65
};
default:
return (struct mp_csp_primaries) {{0}};
}
}
// Get the relative peak of a transfer curve, that is: (source reference /
// display reference), or 0 if there is none (i.e. source has an absolute peak)
float mp_csp_trc_rel_peak(enum mp_csp_trc trc)
{
switch (trc) {
case MP_CSP_TRC_SMPTE_ST2084: return 0.0; // This has a fixed peak
case MP_CSP_TRC_ARIB_STD_B67: return 12.0;
case MP_CSP_TRC_V_LOG: return 46.0855;
}
return 1.0;
}
bool mp_trc_is_hdr(enum mp_csp_trc trc)
{
switch (trc) {
case MP_CSP_TRC_SMPTE_ST2084:
case MP_CSP_TRC_ARIB_STD_B67:
case MP_CSP_TRC_V_LOG:
return true;
}
return false;
}
// Compute the RGB/XYZ matrix as described here:
// http://www.brucelindbloom.com/index.html?Eqn_RGB_XYZ_Matrix.html
static 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
static 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);
}
// get the coefficients of the source -> bt2020 cms matrix
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);
}
// get the coefficients of an SMPTE 428-1 xyz -> rgb conversion matrix
// intent = the rendering intent used to convert to the target primaries
static void mp_get_xyz2rgb_coeffs(struct mp_csp_params *params,
enum mp_render_intent intent, struct mp_cmat *m)
{
struct mp_csp_primaries prim = mp_get_csp_primaries(params->primaries);
float brightness = params->brightness;
mp_get_rgb2xyz_matrix(prim, m->m);
mp_invert_matrix3x3(m->m);
// 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, m->m);
}
// 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.
brightness *= fabs(brightness);
for (int i = 0; i < 3; i++)
m->c[i] = brightness;
}
// Get multiplication factor required if image data is fit within the LSBs of a
// higher smaller bit depth isfixed-point texture data.
double mp_get_csp_mul(enum mp_csp csp, int input_bits, int texture_bits)
{
assert(texture_bits >= input_bits);
// Convenience for some irrelevant cases, e.g. rgb565 or disabling expansion.
if (!input_bits)
return 1;
// RGB always uses the full range available.
if (csp == MP_CSP_RGB)
return ((1LL << input_bits) - 1.) / ((1LL << texture_bits) - 1.);
if (csp == MP_CSP_XYZ)
return 1;
// High bit depth YUV uses a range shifted from 8 bit.
return (1LL << input_bits) / ((1LL << texture_bits) - 1.) * 255 / 256;
}
/* Fill in the Y, U, V vectors of a yuv-to-rgb 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(struct mp_cmat *mat, float lr, float lg, float lb)
{
assert(fabs(lr+lg+lb - 1) < 1e-6);
*mat = (struct mp_cmat) {
{ {1, 0, 2 * (1-lr) },
{1, -2 * (1-lb) * lb/lg, -2 * (1-lr) * lr/lg },
{1, 2 * (1-lb), 0 } },
// Constant coefficients (mat->c) not set here
};
}
// get the coefficients of the yuv -> rgb conversion matrix
void mp_get_csp_matrix(struct mp_csp_params *params, struct mp_cmat *m)
{
int colorspace = params->colorspace;
if (colorspace <= MP_CSP_AUTO || colorspace >= MP_CSP_COUNT)
colorspace = MP_CSP_BT_601;
int levels_in = params->levels_in;
if (levels_in <= MP_CSP_LEVELS_AUTO || levels_in >= MP_CSP_LEVELS_COUNT)
levels_in = MP_CSP_LEVELS_TV;
switch (colorspace) {
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.
*m = (struct mp_cmat){{{0, 0, 1}, {1, 0, 0}, {0, 1, 0}}};
break;
}
case MP_CSP_RGB: {
*m = (struct mp_cmat){{{1, 0, 0}, {0, 1, 0}, {0, 0, 1}}};
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_INTENT_RELATIVE_COLORIMETRIC, m);
levels_in = -1;
break;
}
case MP_CSP_YCGCO: {
*m = (struct mp_cmat) {
{{1, -1, 1},
{1, 1, 0},
{1, -1, -1}},
};
break;
}
default:
abort();
};
if ((colorspace == MP_CSP_BT_601 || colorspace == MP_CSP_BT_709 ||
colorspace == MP_CSP_SMPTE_240M || colorspace == MP_CSP_BT_2020_NC))
{
// Hue is equivalent to rotating input [U, V] subvector around the origin.
// Saturation scales [U, V].
float huecos = params->gray ? 0 : params->saturation * cos(params->hue);
float huesin = params->gray ? 0 : params->saturation * sin(params->hue);
for (int i = 0; i < 3; i++) {
float u = m->m[i][1], v = m->m[i][2];
m->m[i][1] = huecos * u - huesin * v;
m->m[i][2] = huesin * u + huecos * v;
}
}
// The values below are written in 0-255 scale - thus bring s into range.
double s =
mp_get_csp_mul(colorspace, params->input_bits, params->texture_bits) / 255;
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->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;
// Contrast scales the output value range (gain)
ymul *= params->contrast;
cmul *= params->contrast;
for (int i = 0; i < 3; i++) {
m->m[i][0] *= ymul;
m->m[i][1] *= cmul;
m->m[i][2] *= cmul;
// Set c so that Y=umin,UV=cmid maps to RGB=min (black to black),
// also add brightness offset (black lift)
m->c[i] = rgblev.min - m->m[i][0] * yuvlev.ymin
- (m->m[i][1] + m->m[i][2]) * yuvlev.cmid
+ params->brightness;
}
}
// Set colorspace related fields in p from f. Don't touch other fields.
void mp_csp_set_image_params(struct mp_csp_params *params,
const struct mp_image_params *imgparams)
{
struct mp_image_params p = *imgparams;
mp_image_params_guess_csp(&p); // ensure consistency
params->colorspace = p.colorspace;
params->levels_in = p.colorlevels;
params->primaries = p.primaries;
}
// 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 * M_PI;
params->saturation = (eq->values[MP_CSP_EQ_SATURATION] + 100) / 100.0;
params->gamma = exp(log(8.0) * eq->values[MP_CSP_EQ_GAMMA] / 100.0);
params->levels_out = eq->values[MP_CSP_EQ_OUTPUT_LEVELS];
}
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_cmat(struct mp_cmat *out, struct mp_cmat *in)
{
*out = *in;
mp_invert_matrix3x3(out->m);
// fix the constant coefficient
// rgb = M * yuv + C
// M^-1 * rgb = yuv + M^-1 * C
// yuv = M^-1 * rgb - M^-1 * C
// ^^^^^^^^^^
out->c[0] = -(out->m[0][0] * in->c[0] + out->m[0][1] * in->c[1] + out->m[0][2] * in->c[2]);
out->c[1] = -(out->m[1][0] * in->c[0] + out->m[1][1] * in->c[1] + out->m[1][2] * in->c[2]);
out->c[2] = -(out->m[2][0] * in->c[0] + out->m[2][1] * in->c[1] + out->m[2][2] * in->c[2]);
}
// Multiply the color in c with the given matrix.
// i/o is {R, G, B} or {Y, U, V} (depending on input/output and matrix), using
// a fixed point representation with the given number of bits (so for bits==8,
// [0,255] maps to [0,1]). The output is clipped to the range as needed.
void mp_map_fixp_color(struct mp_cmat *matrix, int ibits, int in[3],
int obits, int out[3])
{
for (int i = 0; i < 3; i++) {
double val = matrix->c[i];
for (int x = 0; x < 3; x++)
val += matrix->m[i][x] * in[x] / ((1 << ibits) - 1);
int ival = lrint(val * ((1 << obits) - 1));
out[i] = av_clip(ival, 0, (1 << obits) - 1);
}
}