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/** 21 * @file Colorspace functions for libavutil 22 * @author Ronald S. Bultje <rsbultje@gmail.com> 23 * @author Leo Izen <leo.izen@gmail.com> 24 */ 25 26#include <stdlib.h> 27 28#include "attributes.h" 29#include "csp.h" 30#include "pixfmt.h" 31#include "rational.h" 32 33#define AVR(d) { (int)(d * 100000 + 0.5), 100000 } 34 35/* 36 * All constants explained in e.g. https://linuxtv.org/downloads/v4l-dvb-apis/ch02s06.html 37 * The older ones (bt470bg/m) are also explained in their respective ITU docs 38 * (e.g. https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.470-5-199802-S!!PDF-E.pdf) 39 * whereas the newer ones can typically be copied directly from wikipedia :) 40 */ 41static const struct AVLumaCoefficients luma_coefficients[AVCOL_SPC_NB] = { 42 [AVCOL_SPC_FCC] = { AVR(0.30), AVR(0.59), AVR(0.11) }, 43 [AVCOL_SPC_BT470BG] = { AVR(0.299), AVR(0.587), AVR(0.114) }, 44 [AVCOL_SPC_SMPTE170M] = { AVR(0.299), AVR(0.587), AVR(0.114) }, 45 [AVCOL_SPC_BT709] = { AVR(0.2126), AVR(0.7152), AVR(0.0722) }, 46 [AVCOL_SPC_SMPTE240M] = { AVR(0.212), AVR(0.701), AVR(0.087) }, 47 [AVCOL_SPC_YCOCG] = { AVR(0.25), AVR(0.5), AVR(0.25) }, 48 [AVCOL_SPC_RGB] = { AVR(1), AVR(1), AVR(1) }, 49 [AVCOL_SPC_BT2020_NCL] = { AVR(0.2627), AVR(0.6780), AVR(0.0593) }, 50 [AVCOL_SPC_BT2020_CL] = { AVR(0.2627), AVR(0.6780), AVR(0.0593) }, 51}; 52 53const struct AVLumaCoefficients *av_csp_luma_coeffs_from_avcsp(enum AVColorSpace csp) 54{ 55 const AVLumaCoefficients *coeffs; 56 57 if (csp >= AVCOL_SPC_NB) 58 return NULL; 59 coeffs = &luma_coefficients[csp]; 60 if (!coeffs->cr.num) 61 return NULL; 62 63 return coeffs; 64} 65 66#define WP_D65 { AVR(0.3127), AVR(0.3290) } 67#define WP_C { AVR(0.3100), AVR(0.3160) } 68#define WP_DCI { AVR(0.3140), AVR(0.3510) } 69#define WP_E { {1, 3}, {1, 3} } 70 71static const AVColorPrimariesDesc color_primaries[AVCOL_PRI_NB] = { 72 [AVCOL_PRI_BT709] = { WP_D65, { { AVR(0.640), AVR(0.330) }, { AVR(0.300), AVR(0.600) }, { AVR(0.150), AVR(0.060) } } }, 73 [AVCOL_PRI_BT470M] = { WP_C, { { AVR(0.670), AVR(0.330) }, { AVR(0.210), AVR(0.710) }, { AVR(0.140), AVR(0.080) } } }, 74 [AVCOL_PRI_BT470BG] = { WP_D65, { { AVR(0.640), AVR(0.330) }, { AVR(0.290), AVR(0.600) }, { AVR(0.150), AVR(0.060) } } }, 75 [AVCOL_PRI_SMPTE170M] = { WP_D65, { { AVR(0.630), AVR(0.340) }, { AVR(0.310), AVR(0.595) }, { AVR(0.155), AVR(0.070) } } }, 76 [AVCOL_PRI_SMPTE240M] = { WP_D65, { { AVR(0.630), AVR(0.340) }, { AVR(0.310), AVR(0.595) }, { AVR(0.155), AVR(0.070) } } }, 77 [AVCOL_PRI_SMPTE428] = { WP_E, { { AVR(0.735), AVR(0.265) }, { AVR(0.274), AVR(0.718) }, { AVR(0.167), AVR(0.009) } } }, 78 [AVCOL_PRI_SMPTE431] = { WP_DCI, { { AVR(0.680), AVR(0.320) }, { AVR(0.265), AVR(0.690) }, { AVR(0.150), AVR(0.060) } } }, 79 [AVCOL_PRI_SMPTE432] = { WP_D65, { { AVR(0.680), AVR(0.320) }, { AVR(0.265), AVR(0.690) }, { AVR(0.150), AVR(0.060) } } }, 80 [AVCOL_PRI_FILM] = { WP_C, { { AVR(0.681), AVR(0.319) }, { AVR(0.243), AVR(0.692) }, { AVR(0.145), AVR(0.049) } } }, 81 [AVCOL_PRI_BT2020] = { WP_D65, { { AVR(0.708), AVR(0.292) }, { AVR(0.170), AVR(0.797) }, { AVR(0.131), AVR(0.046) } } }, 82 [AVCOL_PRI_JEDEC_P22] = { WP_D65, { { AVR(0.630), AVR(0.340) }, { AVR(0.295), AVR(0.605) }, { AVR(0.155), AVR(0.077) } } }, 83}; 84 85const AVColorPrimariesDesc *av_csp_primaries_desc_from_id(enum AVColorPrimaries prm) 86{ 87 const AVColorPrimariesDesc *p; 88 89 if (prm >= AVCOL_PRI_NB) 90 return NULL; 91 p = &color_primaries[prm]; 92 if (!p->prim.r.x.num) 93 return NULL; 94 95 return p; 96} 97 98static av_always_inline AVRational abs_sub_q(AVRational r1, AVRational r2) 99{ 100 AVRational diff = av_sub_q(r1, r2); 101 /* denominator assumed to be positive */ 102 return av_make_q(abs(diff.num), diff.den); 103} 104 105enum AVColorPrimaries av_csp_primaries_id_from_desc(const AVColorPrimariesDesc *prm) 106{ 107 AVRational delta; 108 109 for (enum AVColorPrimaries p = 0; p < AVCOL_PRI_NB; p++) { 110 const AVColorPrimariesDesc *ref = &color_primaries[p]; 111 if (!ref->prim.r.x.num) 112 continue; 113 114 delta = abs_sub_q(prm->prim.r.x, ref->prim.r.x); 115 delta = av_add_q(delta, abs_sub_q(prm->prim.r.y, ref->prim.r.y)); 116 delta = av_add_q(delta, abs_sub_q(prm->prim.g.x, ref->prim.g.x)); 117 delta = av_add_q(delta, abs_sub_q(prm->prim.g.y, ref->prim.g.y)); 118 delta = av_add_q(delta, abs_sub_q(prm->prim.b.x, ref->prim.b.x)); 119 delta = av_add_q(delta, abs_sub_q(prm->prim.b.y, ref->prim.b.y)); 120 delta = av_add_q(delta, abs_sub_q(prm->wp.x, ref->wp.x)); 121 delta = av_add_q(delta, abs_sub_q(prm->wp.y, ref->wp.y)); 122 123 if (av_cmp_q(delta, av_make_q(1, 1000)) < 0) 124 return p; 125 } 126 127 return AVCOL_PRI_UNSPECIFIED; 128} 129