FFmpeg
colorspace.c
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1 /*
2  * Copyright (c) 2016 Ronald S. Bultje <rsbultje@gmail.com>
3  * This file is part of FFmpeg.
4  *
5  * FFmpeg is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2.1 of the License, or (at your option) any later version.
9  *
10  * FFmpeg is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public
16  * License along with FFmpeg; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
20 #include "libavutil/frame.h"
22 #include "libavutil/pixdesc.h"
23 
24 #include "colorspace.h"
25 
26 
27 void ff_matrix_invert_3x3(const double in[3][3], double out[3][3])
28 {
29  double m00 = in[0][0], m01 = in[0][1], m02 = in[0][2],
30  m10 = in[1][0], m11 = in[1][1], m12 = in[1][2],
31  m20 = in[2][0], m21 = in[2][1], m22 = in[2][2];
32  int i, j;
33  double det;
34 
35  out[0][0] = (m11 * m22 - m21 * m12);
36  out[0][1] = -(m01 * m22 - m21 * m02);
37  out[0][2] = (m01 * m12 - m11 * m02);
38  out[1][0] = -(m10 * m22 - m20 * m12);
39  out[1][1] = (m00 * m22 - m20 * m02);
40  out[1][2] = -(m00 * m12 - m10 * m02);
41  out[2][0] = (m10 * m21 - m20 * m11);
42  out[2][1] = -(m00 * m21 - m20 * m01);
43  out[2][2] = (m00 * m11 - m10 * m01);
44 
45  det = m00 * out[0][0] + m10 * out[0][1] + m20 * out[0][2];
46  det = 1.0 / det;
47 
48  for (i = 0; i < 3; i++) {
49  for (j = 0; j < 3; j++)
50  out[i][j] *= det;
51  }
52 }
53 
54 void ff_matrix_mul_3x3(double dst[3][3],
55  const double src1[3][3], const double src2[3][3])
56 {
57  int m, n;
58 
59  for (m = 0; m < 3; m++)
60  for (n = 0; n < 3; n++)
61  dst[m][n] = src2[m][0] * src1[0][n] +
62  src2[m][1] * src1[1][n] +
63  src2[m][2] * src1[2][n];
64 }
65 
66 void ff_matrix_mul_3x3_vec(double dst[3], const double vec[3], const double mat[3][3])
67 {
68  int m;
69 
70  for (m = 0; m < 3; m++)
71  dst[m] = vec[0] * mat[m][0] +
72  vec[1] * mat[m][1] +
73  vec[2] * mat[m][2];
74 }
75 
76 /*
77  * see e.g. http://www.brucelindbloom.com/index.html?Eqn_RGB_XYZ_Matrix.html
78  */
80  const AVWhitepointCoefficients *wp,
81  double rgb2xyz[3][3])
82 {
83  double i[3][3], sr, sg, sb, zw;
84  double xr = av_q2d(coeffs->r.x), yr = av_q2d(coeffs->r.y);
85  double xg = av_q2d(coeffs->g.x), yg = av_q2d(coeffs->g.y);
86  double xb = av_q2d(coeffs->b.x), yb = av_q2d(coeffs->b.y);
87  double xw = av_q2d(wp->x), yw = av_q2d(wp->y);
88 
89  rgb2xyz[0][0] = xr / yr;
90  rgb2xyz[0][1] = xg / yg;
91  rgb2xyz[0][2] = xb / yb;
92  rgb2xyz[1][0] = rgb2xyz[1][1] = rgb2xyz[1][2] = 1.0;
93  rgb2xyz[2][0] = (1.0 - xr - yr) / yr;
94  rgb2xyz[2][1] = (1.0 - xg - yg) / yg;
95  rgb2xyz[2][2] = (1.0 - xb - yb) / yb;
96  ff_matrix_invert_3x3(rgb2xyz, i);
97  zw = 1.0 - xw - yw;
98  sr = i[0][0] * xw + i[0][1] * yw + i[0][2] * zw;
99  sg = i[1][0] * xw + i[1][1] * yw + i[1][2] * zw;
100  sb = i[2][0] * xw + i[2][1] * yw + i[2][2] * zw;
101  rgb2xyz[0][0] *= sr;
102  rgb2xyz[0][1] *= sg;
103  rgb2xyz[0][2] *= sb;
104  rgb2xyz[1][0] *= sr;
105  rgb2xyz[1][1] *= sg;
106  rgb2xyz[1][2] *= sb;
107  rgb2xyz[2][0] *= sr;
108  rgb2xyz[2][1] *= sg;
109  rgb2xyz[2][2] *= sb;
110 }
111 static const double ycgco_matrix[3][3] =
112 {
113  { 0.25, 0.5, 0.25 },
114  { -0.25, 0.5, -0.25 },
115  { 0.5, 0, -0.5 },
116 };
117 
118 static const double gbr_matrix[3][3] =
119 {
120  { 0, 1, 0 },
121  { 0, -0.5, 0.5 },
122  { 0.5, -0.5, 0 },
123 };
124 
126  double rgb2yuv[3][3])
127 {
128  double bscale, rscale;
129  double cr = av_q2d(coeffs->cr), cg = av_q2d(coeffs->cg), cb = av_q2d(coeffs->cb);
130 
131  // special ycgco matrix
132  if (cr == 0.25 && cg == 0.5 && cb == 0.25) {
133  memcpy(rgb2yuv, ycgco_matrix, sizeof(double) * 9);
134  return;
135  } else if (cr == 1 && cg == 1 && cb == 1) {
136  memcpy(rgb2yuv, gbr_matrix, sizeof(double) * 9);
137  return;
138  }
139 
140  rgb2yuv[0][0] = cr;
141  rgb2yuv[0][1] = cg;
142  rgb2yuv[0][2] = cb;
143  bscale = 0.5 / (cb - 1.0);
144  rscale = 0.5 / (cr - 1.0);
145  rgb2yuv[1][0] = bscale * cr;
146  rgb2yuv[1][1] = bscale * cg;
147  rgb2yuv[1][2] = 0.5;
148  rgb2yuv[2][0] = 0.5;
149  rgb2yuv[2][1] = rscale * cg;
150  rgb2yuv[2][2] = rscale * cb;
151 }
152 
154 {
156  double peak = 0;
157 
158  if (sd) {
160  peak = clm->MaxCLL / REFERENCE_WHITE;
161  }
162 
164  if (!peak && sd) {
166  if (metadata->has_luminance)
167  peak = av_q2d(metadata->max_luminance) / REFERENCE_WHITE;
168  }
169 
170  // For untagged source, use peak of 10000 if SMPTE ST.2084
171  // otherwise assume HLG with reference display peak 1000.
172  if (!peak)
173  peak = in->color_trc == AVCOL_TRC_SMPTE2084 ? 100.0f : 10.0f;
174 
175  return peak;
176 }
177 
178 void ff_update_hdr_metadata(AVFrame *in, double peak)
179 {
181 
182  if (sd) {
184  clm->MaxCLL = (unsigned)(peak * REFERENCE_WHITE);
185  }
186 
188  if (sd) {
190  if (metadata->has_luminance)
191  metadata->max_luminance = av_d2q(peak * REFERENCE_WHITE, 10000);
192  }
193 }
AVLumaCoefficients::cr
AVRational cr
Definition: csp.h:40
AVFrame::color_trc
enum AVColorTransferCharacteristic color_trc
Definition: frame.h:582
AVMasteringDisplayMetadata::max_luminance
AVRational max_luminance
Max luminance of mastering display (cd/m^2).
Definition: mastering_display_metadata.h:57
gbr_matrix
static const double gbr_matrix[3][3]
Definition: colorspace.c:118
out
FILE * out
Definition: movenc.c:54
cb
static double cb(void *priv, double x, double y)
Definition: vf_geq.c:239
av_frame_get_side_data
AVFrameSideData * av_frame_get_side_data(const AVFrame *frame, enum AVFrameSideDataType type)
Definition: frame.c:691
ff_matrix_invert_3x3
void ff_matrix_invert_3x3(const double in[3][3], double out[3][3])
Definition: colorspace.c:27
src1
const pixel * src1
Definition: h264pred_template.c:421
AVMasteringDisplayMetadata::has_luminance
int has_luminance
Flag indicating whether the luminance (min_ and max_) have been set.
Definition: mastering_display_metadata.h:67
ycgco_matrix
static const double ycgco_matrix[3][3]
Definition: colorspace.c:111
AVContentLightMetadata::MaxCLL
unsigned MaxCLL
Max content light level (cd/m^2).
Definition: mastering_display_metadata.h:102
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
pixdesc.h
rgb2yuv
static const char rgb2yuv[]
Definition: vf_scale_vulkan.c:68
ff_determine_signal_peak
double ff_determine_signal_peak(AVFrame *in)
Definition: colorspace.c:153
AVLumaCoefficients
Struct containing luma coefficients to be used for RGB to YUV/YCoCg, or similar calculations.
Definition: csp.h:39
AVContentLightMetadata
Content light level needed by to transmit HDR over HDMI (CTA-861.3).
Definition: mastering_display_metadata.h:98
AVPrimaryCoefficients
Struct defining the red, green, and blue primary locations in terms of CIE 1931 chromaticity x and y.
Definition: csp.h:55
colorspace.h
av_q2d
static double av_q2d(AVRational a)
Convert an AVRational to a double.
Definition: rational.h:104
AVLumaCoefficients::cg
AVRational cg
Definition: csp.h:40
ff_matrix_mul_3x3_vec
void ff_matrix_mul_3x3_vec(double dst[3], const double vec[3], const double mat[3][3])
Definition: colorspace.c:66
if
if(ret)
Definition: filter_design.txt:179
ff_matrix_mul_3x3
void ff_matrix_mul_3x3(double dst[3][3], const double src1[3][3], const double src2[3][3])
Definition: colorspace.c:54
AV_FRAME_DATA_MASTERING_DISPLAY_METADATA
@ AV_FRAME_DATA_MASTERING_DISPLAY_METADATA
Mastering display metadata associated with a video frame.
Definition: frame.h:120
AVCIExy
Struct containing chromaticity x and y values for the standard CIE 1931 chromaticity definition.
Definition: csp.h:47
AVCIExy::x
AVRational x
Definition: csp.h:48
AVCOL_TRC_SMPTE2084
@ AVCOL_TRC_SMPTE2084
SMPTE ST 2084 for 10-, 12-, 14- and 16-bit systems.
Definition: pixfmt.h:544
AVPrimaryCoefficients::b
AVCIExy b
Definition: csp.h:56
AVPrimaryCoefficients::r
AVCIExy r
Definition: csp.h:56
ff_update_hdr_metadata
void ff_update_hdr_metadata(AVFrame *in, double peak)
Definition: colorspace.c:178
AVFrameSideData::data
uint8_t * data
Definition: frame.h:233
AVPrimaryCoefficients::g
AVCIExy g
Definition: csp.h:56
frame.h
REFERENCE_WHITE
#define REFERENCE_WHITE
Definition: colorspace.h:27
ff_fill_rgb2yuv_table
void ff_fill_rgb2yuv_table(const AVLumaCoefficients *coeffs, double rgb2yuv[3][3])
Definition: colorspace.c:125
AV_FRAME_DATA_CONTENT_LIGHT_LEVEL
@ AV_FRAME_DATA_CONTENT_LIGHT_LEVEL
Content light level (based on CTA-861.3).
Definition: frame.h:137
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
src2
const pixel * src2
Definition: h264pred_template.c:422
av_d2q
AVRational av_d2q(double d, int max)
Convert a double precision floating point number to a rational.
Definition: rational.c:106
AVMasteringDisplayMetadata
Mastering display metadata capable of representing the color volume of the display used to master the...
Definition: mastering_display_metadata.h:38
AVCIExy::y
AVRational y
Definition: csp.h:48
ff_fill_rgb2xyz_table
void ff_fill_rgb2xyz_table(const AVPrimaryCoefficients *coeffs, const AVWhitepointCoefficients *wp, double rgb2xyz[3][3])
Definition: colorspace.c:79
mastering_display_metadata.h
AVFrameSideData
Structure to hold side data for an AVFrame.
Definition: frame.h:231
cr
static double cr(void *priv, double x, double y)
Definition: vf_geq.c:240
AVLumaCoefficients::cb
AVRational cb
Definition: csp.h:40