| /* | |
| * Copyright (c) 2014 Tim Walker <[email protected]> | |
| * | |
| * This file is part of FFmpeg. | |
| * | |
| * FFmpeg is free software; you can redistribute it and/or | |
| * modify it under the terms of the GNU Lesser General Public | |
| * License as published by the Free Software Foundation; either | |
| * version 2.1 of the License, or (at your option) any later version. | |
| * | |
| * FFmpeg is distributed in the hope that it will be useful, | |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| * Lesser General Public License for more details. | |
| * | |
| * You should have received a copy of the GNU Lesser General Public | |
| * License along with FFmpeg; if not, write to the Free Software | |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| */ | |
| /** | |
| * @file | |
| * audio downmix medatata | |
| */ | |
| /** | |
| * @addtogroup lavu_audio | |
| * @{ | |
| */ | |
| /** | |
| * @defgroup downmix_info Audio downmix metadata | |
| * @{ | |
| */ | |
| /** | |
| * Possible downmix types. | |
| */ | |
| enum AVDownmixType { | |
| AV_DOWNMIX_TYPE_UNKNOWN, /**< Not indicated. */ | |
| AV_DOWNMIX_TYPE_LORO, /**< Lo/Ro 2-channel downmix (Stereo). */ | |
| AV_DOWNMIX_TYPE_LTRT, /**< Lt/Rt 2-channel downmix, Dolby Surround compatible. */ | |
| AV_DOWNMIX_TYPE_DPLII, /**< Lt/Rt 2-channel downmix, Dolby Pro Logic II compatible. */ | |
| AV_DOWNMIX_TYPE_NB /**< Number of downmix types. Not part of ABI. */ | |
| }; | |
| /** | |
| * This structure describes optional metadata relevant to a downmix procedure. | |
| * | |
| * All fields are set by the decoder to the value indicated in the audio | |
| * bitstream (if present), or to a "sane" default otherwise. | |
| */ | |
| typedef struct AVDownmixInfo { | |
| /** | |
| * Type of downmix preferred by the mastering engineer. | |
| */ | |
| enum AVDownmixType preferred_downmix_type; | |
| /** | |
| * Absolute scale factor representing the nominal level of the center | |
| * channel during a regular downmix. | |
| */ | |
| double center_mix_level; | |
| /** | |
| * Absolute scale factor representing the nominal level of the center | |
| * channel during an Lt/Rt compatible downmix. | |
| */ | |
| double center_mix_level_ltrt; | |
| /** | |
| * Absolute scale factor representing the nominal level of the surround | |
| * channels during a regular downmix. | |
| */ | |
| double surround_mix_level; | |
| /** | |
| * Absolute scale factor representing the nominal level of the surround | |
| * channels during an Lt/Rt compatible downmix. | |
| */ | |
| double surround_mix_level_ltrt; | |
| /** | |
| * Absolute scale factor representing the level at which the LFE data is | |
| * mixed into L/R channels during downmixing. | |
| */ | |
| double lfe_mix_level; | |
| } AVDownmixInfo; | |
| /** | |
| * Get a frame's AV_FRAME_DATA_DOWNMIX_INFO side data for editing. | |
| * | |
| * If the side data is absent, it is created and added to the frame. | |
| * | |
| * @param frame the frame for which the side data is to be obtained or created | |
| * | |
| * @return the AVDownmixInfo structure to be edited by the caller, or NULL if | |
| * the structure cannot be allocated. | |
| */ | |
| AVDownmixInfo *av_downmix_info_update_side_data(AVFrame *frame); | |
| /** | |
| * @} | |
| */ | |
| /** | |
| * @} | |
| */ | |