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 #ifndef AVUTIL_CSP_H 21 #define AVUTIL_CSP_H 22 23 #include "pixfmt.h" 24 #include "rational.h" 25 26 /** 27 * @file Colorspace value utility functions for libavutil. 28 * @author Ronald S. Bultje <rsbultje@gmail.com> 29 * @author Leo Izen <leo.izen@gmail.com> 30 * @defgroup lavu_math_csp Colorspace Utility 31 * @ingroup lavu_math 32 * @{ 33 */ 34 35 /** 36 * Struct containing luma coefficients to be used for RGB to YUV/YCoCg, or similar 37 * calculations. 38 */ 39 typedef struct AVLumaCoefficients { 40 AVRational cr, cg, cb; 41 } AVLumaCoefficients; 42 43 /** 44 * Struct containing chromaticity x and y values for the standard CIE 1931 45 * chromaticity definition. 46 */ 47 typedef struct AVCIExy { 48 AVRational x, y; 49 } AVCIExy; 50 51 /** 52 * Struct defining the red, green, and blue primary locations in terms of CIE 53 * 1931 chromaticity x and y. 54 */ 55 typedef struct AVPrimaryCoefficients { 56 AVCIExy r, g, b; 57 } AVPrimaryCoefficients; 58 59 /** 60 * Struct defining white point location in terms of CIE 1931 chromaticity x 61 * and y. 62 */ 63 typedef AVCIExy AVWhitepointCoefficients; 64 65 /** 66 * Struct that contains both white point location and primaries location, providing 67 * the complete description of a color gamut. 68 */ 69 typedef struct AVColorPrimariesDesc { 70 AVWhitepointCoefficients wp; 71 AVPrimaryCoefficients prim; 72 } AVColorPrimariesDesc; 73 74 /** 75 * Retrieves the Luma coefficients necessary to construct a conversion matrix 76 * from an enum constant describing the colorspace. 77 * @param csp An enum constant indicating YUV or similar colorspace. 78 * @return The Luma coefficients associated with that colorspace, or NULL 79 * if the constant is unknown to libavutil. 80 */ 81 const AVLumaCoefficients *av_csp_luma_coeffs_from_avcsp(enum AVColorSpace csp); 82 83 /** 84 * Retrieves a complete gamut description from an enum constant describing the 85 * color primaries. 86 * @param prm An enum constant indicating primaries 87 * @return A description of the colorspace gamut associated with that enum 88 * constant, or NULL if the constant is unknown to libavutil. 89 */ 90 const AVColorPrimariesDesc *av_csp_primaries_desc_from_id(enum AVColorPrimaries prm); 91 92 /** 93 * Detects which enum AVColorPrimaries constant corresponds to the given complete 94 * gamut description. 95 * @see enum AVColorPrimaries 96 * @param prm A description of the colorspace gamut 97 * @return The enum constant associated with this gamut, or 98 * AVCOL_PRI_UNSPECIFIED if no clear match can be idenitified. 99 */ 100 enum AVColorPrimaries av_csp_primaries_id_from_desc(const AVColorPrimariesDesc *prm); 101 102 /** 103 * @} 104 */ 105 106 #endif /* AVUTIL_CSP_H */ 107