| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /* | ||
| 2 | * Copyright (c) 2014 Tim Walker <tdskywalker@gmail.com> | ||
| 3 | * | ||
| 4 | * This file is part of FFmpeg. | ||
| 5 | * | ||
| 6 | * FFmpeg is free software; you can redistribute it and/or | ||
| 7 | * modify it under the terms of the GNU Lesser General Public | ||
| 8 | * License as published by the Free Software Foundation; either | ||
| 9 | * version 2.1 of the License, or (at your option) any later version. | ||
| 10 | * | ||
| 11 | * FFmpeg is distributed in the hope that it will be useful, | ||
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
| 14 | * Lesser General Public License for more details. | ||
| 15 | * | ||
| 16 | * You should have received a copy of the GNU Lesser General Public | ||
| 17 | * License along with FFmpeg; if not, write to the Free Software | ||
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
| 19 | */ | ||
| 20 | |||
| 21 | #ifndef AVUTIL_DOWNMIX_INFO_H | ||
| 22 | #define AVUTIL_DOWNMIX_INFO_H | ||
| 23 | |||
| 24 | #include "avassert.h" | ||
| 25 | #include "frame.h" | ||
| 26 | |||
| 27 | /** | ||
| 28 | * @file | ||
| 29 | * audio downmix medatata | ||
| 30 | */ | ||
| 31 | |||
| 32 | /** | ||
| 33 | * @addtogroup lavu_audio | ||
| 34 | * @{ | ||
| 35 | */ | ||
| 36 | |||
| 37 | /** | ||
| 38 | * @defgroup downmix_info Audio downmix metadata | ||
| 39 | * @{ | ||
| 40 | */ | ||
| 41 | |||
| 42 | /** | ||
| 43 | * Possible downmix types. | ||
| 44 | */ | ||
| 45 | enum AVDownmixType { | ||
| 46 | AV_DOWNMIX_TYPE_UNKNOWN, /**< Not indicated. */ | ||
| 47 | AV_DOWNMIX_TYPE_LORO, /**< Lo/Ro 2-channel downmix (Stereo). */ | ||
| 48 | AV_DOWNMIX_TYPE_LTRT, /**< Lt/Rt 2-channel downmix, Dolby Surround compatible. */ | ||
| 49 | AV_DOWNMIX_TYPE_DPLII, /**< Lt/Rt 2-channel downmix, Dolby Pro Logic II compatible. */ | ||
| 50 | AV_DOWNMIX_TYPE_NB /**< Number of downmix types. Not part of ABI. */ | ||
| 51 | }; | ||
| 52 | |||
| 53 | /** | ||
| 54 | * This structure describes optional metadata relevant to a downmix procedure. | ||
| 55 | * | ||
| 56 | * All fields are set by the decoder to the value indicated in the audio | ||
| 57 | * bitstream (if present), or to a "sane" default otherwise. | ||
| 58 | */ | ||
| 59 | typedef struct AVDownmixInfo { | ||
| 60 | /** | ||
| 61 | * Type of downmix preferred by the mastering engineer. | ||
| 62 | */ | ||
| 63 | enum AVDownmixType preferred_downmix_type; | ||
| 64 | |||
| 65 | /** | ||
| 66 | * Absolute scale factor representing the nominal level of the center | ||
| 67 | * channel during a regular downmix. | ||
| 68 | */ | ||
| 69 | double center_mix_level; | ||
| 70 | |||
| 71 | /** | ||
| 72 | * Absolute scale factor representing the nominal level of the center | ||
| 73 | * channel during an Lt/Rt compatible downmix. | ||
| 74 | */ | ||
| 75 | double center_mix_level_ltrt; | ||
| 76 | |||
| 77 | /** | ||
| 78 | * Absolute scale factor representing the nominal level of the surround | ||
| 79 | * channels during a regular downmix. | ||
| 80 | */ | ||
| 81 | double surround_mix_level; | ||
| 82 | |||
| 83 | /** | ||
| 84 | * Absolute scale factor representing the nominal level of the surround | ||
| 85 | * channels during an Lt/Rt compatible downmix. | ||
| 86 | */ | ||
| 87 | double surround_mix_level_ltrt; | ||
| 88 | |||
| 89 | /** | ||
| 90 | * Absolute scale factor representing the level at which the LFE data is | ||
| 91 | * mixed into L/R channels during downmixing. | ||
| 92 | */ | ||
| 93 | double lfe_mix_level; | ||
| 94 | } AVDownmixInfo; | ||
| 95 | |||
| 96 | /** | ||
| 97 | * Get a frame's AV_FRAME_DATA_DOWNMIX_INFO side data for editing. | ||
| 98 | * | ||
| 99 | * If the side data is absent, it is created and added to the frame. | ||
| 100 | * | ||
| 101 | * @param frame the frame for which the side data is to be obtained or created | ||
| 102 | * | ||
| 103 | * @return the AVDownmixInfo structure to be edited by the caller, or NULL if | ||
| 104 | * the structure cannot be allocated. | ||
| 105 | */ | ||
| 106 | AVDownmixInfo *av_downmix_info_update_side_data(AVFrame *frame); | ||
| 107 | |||
| 108 | /** | ||
| 109 | * This structure describes optional metadata relevant to a downmix procedure | ||
| 110 | * in the form of a remixing matrix allocated as an array of AVDownmixCoeff. | ||
| 111 | * Must be allocated with @ref av_downmix_matrix_alloc. | ||
| 112 | * | ||
| 113 | * sizeof(AVDownmixMatrix) is not a part of the ABI and new fields may be | ||
| 114 | * added to it. | ||
| 115 | */ | ||
| 116 | typedef struct AVDownmixMatrix { | ||
| 117 | /** | ||
| 118 | * Type of downmix the coeffs will produce. | ||
| 119 | * Output channel count is derived from this value. | ||
| 120 | */ | ||
| 121 | enum AVDownmixType downmix_type; | ||
| 122 | |||
| 123 | /** | ||
| 124 | * Input channel count. | ||
| 125 | */ | ||
| 126 | int in_ch_count; | ||
| 127 | |||
| 128 | /** | ||
| 129 | * Amount of coefficients in the matrix. | ||
| 130 | */ | ||
| 131 | unsigned int nb_coeffs; | ||
| 132 | |||
| 133 | /** | ||
| 134 | * Offset in bytes from the beginning of this structure at which the array | ||
| 135 | * of coefficients starts. | ||
| 136 | */ | ||
| 137 | size_t coeffs_offset; | ||
| 138 | } AVDownmixMatrix; | ||
| 139 | |||
| 140 | /** | ||
| 141 | * Data type for storing coefficients, which are allocated as a part of | ||
| 142 | * AVDownmixMatrix and should be retrieved with @ref av_downmix_matrix_coeff. | ||
| 143 | */ | ||
| 144 | typedef double AVDownmixCoeff; | ||
| 145 | |||
| 146 | /** | ||
| 147 | * Get a pointer to the coeff that represents the weight of input channel | ||
| 148 | * {@code in} in output channel {@code out}. | ||
| 149 | * in must be between 0 and @ref AVDownmixMatrix.in_ch_count "in_ch_count" - 1. | ||
| 150 | * out must be between 0 and the implicit output channel count from | ||
| 151 | * @ref AVDownmixMatrix.downmix_type "downmix_type" - 1. | ||
| 152 | */ | ||
| 153 | static av_always_inline AVDownmixCoeff* | ||
| 154 | 78 | av_downmix_matrix_coeff(AVDownmixMatrix *dm, unsigned int out, unsigned int in) | |
| 155 | { | ||
| 156 | 78 | AVDownmixCoeff *coeff = (AVDownmixCoeff *)((uint8_t *)dm + dm->coeffs_offset); | |
| 157 | 78 | return &coeff[in + dm->in_ch_count * out]; | |
| 158 | } | ||
| 159 | |||
| 160 | /** | ||
| 161 | * Allocates memory for AVDownmixMatrix of the given type, plus an array of | ||
| 162 | * {@code in_ch_count} times the implicit output channel count from {@code type} | ||
| 163 | * of AVDownmixCoeff and initializes the variables. Can be freed with a normal | ||
| 164 | * av_free() call. | ||
| 165 | * | ||
| 166 | * @param out_size if non-NULL, the size in bytes of the resulting data array is | ||
| 167 | * written here. | ||
| 168 | */ | ||
| 169 | AVDownmixMatrix *av_downmix_matrix_alloc(enum AVDownmixType type, | ||
| 170 | int in_ch_count, size_t *out_size); | ||
| 171 | |||
| 172 | /** | ||
| 173 | * @} | ||
| 174 | */ | ||
| 175 | |||
| 176 | /** | ||
| 177 | * @} | ||
| 178 | */ | ||
| 179 | |||
| 180 | #endif /* AVUTIL_DOWNMIX_INFO_H */ | ||
| 181 |