2 * Copyright (c) 2016 Ronald S. Bultje <rsbultje@gmail.com>
3 * This file is part of FFmpeg.
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.
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.
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
20 #include "libavutil/frame.h"
21 #include "libavutil/mastering_display_metadata.h"
22 #include "libavutil/pixdesc.h"
24 #include "colorspace.h"
27 void ff_matrix_invert_3x3(const double in[3][3], double out[3][3])
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];
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);
45 det = m00 * out[0][0] + m10 * out[0][1] + m20 * out[0][2];
48 for (i = 0; i < 3; i++) {
49 for (j = 0; j < 3; j++)
54 void ff_matrix_mul_3x3(double dst[3][3],
55 const double src1[3][3], const double src2[3][3])
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];
66 * see e.g. http://www.brucelindbloom.com/index.html?Eqn_RGB_XYZ_Matrix.html
68 void ff_fill_rgb2xyz_table(const struct PrimaryCoefficients *coeffs,
69 const struct WhitepointCoefficients *wp,
72 double i[3][3], sr, sg, sb, zw;
74 rgb2xyz[0][0] = coeffs->xr / coeffs->yr;
75 rgb2xyz[0][1] = coeffs->xg / coeffs->yg;
76 rgb2xyz[0][2] = coeffs->xb / coeffs->yb;
77 rgb2xyz[1][0] = rgb2xyz[1][1] = rgb2xyz[1][2] = 1.0;
78 rgb2xyz[2][0] = (1.0 - coeffs->xr - coeffs->yr) / coeffs->yr;
79 rgb2xyz[2][1] = (1.0 - coeffs->xg - coeffs->yg) / coeffs->yg;
80 rgb2xyz[2][2] = (1.0 - coeffs->xb - coeffs->yb) / coeffs->yb;
81 ff_matrix_invert_3x3(rgb2xyz, i);
82 zw = 1.0 - wp->xw - wp->yw;
83 sr = i[0][0] * wp->xw + i[0][1] * wp->yw + i[0][2] * zw;
84 sg = i[1][0] * wp->xw + i[1][1] * wp->yw + i[1][2] * zw;
85 sb = i[2][0] * wp->xw + i[2][1] * wp->yw + i[2][2] * zw;
96 static const double ycgco_matrix[3][3] =
99 { -0.25, 0.5, -0.25 },
103 static const double gbr_matrix[3][3] =
111 * All constants explained in e.g. https://linuxtv.org/downloads/v4l-dvb-apis/ch02s06.html
112 * The older ones (bt470bg/m) are also explained in their respective ITU docs
113 * (e.g. https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.470-5-199802-S!!PDF-E.pdf)
114 * whereas the newer ones can typically be copied directly from wikipedia :)
116 static const struct LumaCoefficients luma_coefficients[AVCOL_SPC_NB] = {
117 [AVCOL_SPC_FCC] = { 0.30, 0.59, 0.11 },
118 [AVCOL_SPC_BT470BG] = { 0.299, 0.587, 0.114 },
119 [AVCOL_SPC_SMPTE170M] = { 0.299, 0.587, 0.114 },
120 [AVCOL_SPC_BT709] = { 0.2126, 0.7152, 0.0722 },
121 [AVCOL_SPC_SMPTE240M] = { 0.212, 0.701, 0.087 },
122 [AVCOL_SPC_YCOCG] = { 0.25, 0.5, 0.25 },
123 [AVCOL_SPC_RGB] = { 1, 1, 1 },
124 [AVCOL_SPC_BT2020_NCL] = { 0.2627, 0.6780, 0.0593 },
125 [AVCOL_SPC_BT2020_CL] = { 0.2627, 0.6780, 0.0593 },
128 const struct LumaCoefficients *ff_get_luma_coefficients(enum AVColorSpace csp)
130 const struct LumaCoefficients *coeffs;
132 if (csp >= AVCOL_SPC_NB)
134 coeffs = &luma_coefficients[csp];
141 void ff_fill_rgb2yuv_table(const struct LumaCoefficients *coeffs,
142 double rgb2yuv[3][3])
144 double bscale, rscale;
146 // special ycgco matrix
147 if (coeffs->cr == 0.25 && coeffs->cg == 0.5 && coeffs->cb == 0.25) {
148 memcpy(rgb2yuv, ycgco_matrix, sizeof(double) * 9);
150 } else if (coeffs->cr == 1 && coeffs->cg == 1 && coeffs->cb == 1) {
151 memcpy(rgb2yuv, gbr_matrix, sizeof(double) * 9);
155 rgb2yuv[0][0] = coeffs->cr;
156 rgb2yuv[0][1] = coeffs->cg;
157 rgb2yuv[0][2] = coeffs->cb;
158 bscale = 0.5 / (coeffs->cb - 1.0);
159 rscale = 0.5 / (coeffs->cr - 1.0);
160 rgb2yuv[1][0] = bscale * coeffs->cr;
161 rgb2yuv[1][1] = bscale * coeffs->cg;
164 rgb2yuv[2][1] = rscale * coeffs->cg;
165 rgb2yuv[2][2] = rscale * coeffs->cb;
168 double ff_determine_signal_peak(AVFrame *in)
170 AVFrameSideData *sd = av_frame_get_side_data(in, AV_FRAME_DATA_CONTENT_LIGHT_LEVEL);
174 AVContentLightMetadata *clm = (AVContentLightMetadata *)sd->data;
175 peak = clm->MaxCLL / REFERENCE_WHITE;
178 sd = av_frame_get_side_data(in, AV_FRAME_DATA_MASTERING_DISPLAY_METADATA);
180 AVMasteringDisplayMetadata *metadata = (AVMasteringDisplayMetadata *)sd->data;
181 if (metadata->has_luminance)
182 peak = av_q2d(metadata->max_luminance) / REFERENCE_WHITE;
185 // For untagged source, use peak of 10000 if SMPTE ST.2084
186 // otherwise assume HLG with reference display peak 1000.
188 peak = in->color_trc == AVCOL_TRC_SMPTE2084 ? 100.0f : 10.0f;
193 void ff_update_hdr_metadata(AVFrame *in, double peak)
195 AVFrameSideData *sd = av_frame_get_side_data(in, AV_FRAME_DATA_CONTENT_LIGHT_LEVEL);
198 AVContentLightMetadata *clm = (AVContentLightMetadata *)sd->data;
199 clm->MaxCLL = (unsigned)(peak * REFERENCE_WHITE);
202 sd = av_frame_get_side_data(in, AV_FRAME_DATA_MASTERING_DISPLAY_METADATA);
204 AVMasteringDisplayMetadata *metadata = (AVMasteringDisplayMetadata *)sd->data;
205 if (metadata->has_luminance)
206 metadata->max_luminance = av_d2q(peak * REFERENCE_WHITE, 10000);