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			Mapping to ITU-R BS.2051-3 "Sound System J" and ITU-R BS.1196-8 "Channel Configuration 19". Signed-off-by: Will Wolcott <wwolcott@netflix.com> Signed-off-by: James Almer <jamrial@gmail.com>
		
			
				
	
	
		
			806 lines
		
	
	
		
			33 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			806 lines
		
	
	
		
			33 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
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|  * Copyright (c) 2008 Peter Ross
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
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| #ifndef AVUTIL_CHANNEL_LAYOUT_H
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| #define AVUTIL_CHANNEL_LAYOUT_H
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| 
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| #include <stdint.h>
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| #include <stdlib.h>
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| 
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| #include "version.h"
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| #include "attributes.h"
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| 
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| /**
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|  * @file
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|  * @ingroup lavu_audio_channels
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|  * Public libavutil channel layout APIs header.
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|  */
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| 
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| 
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| /**
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|  * @defgroup lavu_audio_channels Audio channels
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|  * @ingroup lavu_audio
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|  *
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|  * Audio channel layout utility functions
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|  *
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|  * @{
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|  */
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| 
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| enum AVChannel {
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|     ///< Invalid channel index
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|     AV_CHAN_NONE = -1,
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|     AV_CHAN_FRONT_LEFT,
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|     AV_CHAN_FRONT_RIGHT,
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|     AV_CHAN_FRONT_CENTER,
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|     AV_CHAN_LOW_FREQUENCY,
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|     AV_CHAN_BACK_LEFT,
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|     AV_CHAN_BACK_RIGHT,
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|     AV_CHAN_FRONT_LEFT_OF_CENTER,
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|     AV_CHAN_FRONT_RIGHT_OF_CENTER,
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|     AV_CHAN_BACK_CENTER,
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|     AV_CHAN_SIDE_LEFT,
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|     AV_CHAN_SIDE_RIGHT,
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|     AV_CHAN_TOP_CENTER,
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|     AV_CHAN_TOP_FRONT_LEFT,
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|     AV_CHAN_TOP_FRONT_CENTER,
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|     AV_CHAN_TOP_FRONT_RIGHT,
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|     AV_CHAN_TOP_BACK_LEFT,
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|     AV_CHAN_TOP_BACK_CENTER,
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|     AV_CHAN_TOP_BACK_RIGHT,
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|     /** Stereo downmix. */
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|     AV_CHAN_STEREO_LEFT = 29,
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|     /** See above. */
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|     AV_CHAN_STEREO_RIGHT,
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|     AV_CHAN_WIDE_LEFT,
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|     AV_CHAN_WIDE_RIGHT,
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|     AV_CHAN_SURROUND_DIRECT_LEFT,
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|     AV_CHAN_SURROUND_DIRECT_RIGHT,
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|     AV_CHAN_LOW_FREQUENCY_2,
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|     AV_CHAN_TOP_SIDE_LEFT,
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|     AV_CHAN_TOP_SIDE_RIGHT,
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|     AV_CHAN_BOTTOM_FRONT_CENTER,
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|     AV_CHAN_BOTTOM_FRONT_LEFT,
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|     AV_CHAN_BOTTOM_FRONT_RIGHT,
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| 
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|     /** Channel is empty can be safely skipped. */
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|     AV_CHAN_UNUSED = 0x200,
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| 
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|     /** Channel contains data, but its position is unknown. */
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|     AV_CHAN_UNKNOWN = 0x300,
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| 
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|     /**
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|      * Range of channels between AV_CHAN_AMBISONIC_BASE and
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|      * AV_CHAN_AMBISONIC_END represent Ambisonic components using the ACN system.
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|      *
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|      * Given a channel id `<i>` between AV_CHAN_AMBISONIC_BASE and
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|      * AV_CHAN_AMBISONIC_END (inclusive), the ACN index of the channel `<n>` is
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|      * `<n> = <i> - AV_CHAN_AMBISONIC_BASE`.
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|      *
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|      * @note these values are only used for AV_CHANNEL_ORDER_CUSTOM channel
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|      * orderings, the AV_CHANNEL_ORDER_AMBISONIC ordering orders the channels
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|      * implicitly by their position in the stream.
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|      */
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|     AV_CHAN_AMBISONIC_BASE = 0x400,
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|     // leave space for 1024 ids, which correspond to maximum order-32 harmonics,
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|     // which should be enough for the foreseeable use cases
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|     AV_CHAN_AMBISONIC_END  = 0x7ff,
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| };
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| 
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| enum AVChannelOrder {
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|     /**
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|      * Only the channel count is specified, without any further information
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|      * about the channel order.
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|      */
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|     AV_CHANNEL_ORDER_UNSPEC,
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|     /**
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|      * The native channel order, i.e. the channels are in the same order in
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|      * which they are defined in the AVChannel enum. This supports up to 63
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|      * different channels.
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|      */
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|     AV_CHANNEL_ORDER_NATIVE,
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|     /**
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|      * The channel order does not correspond to any other predefined order and
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|      * is stored as an explicit map. For example, this could be used to support
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|      * layouts with 64 or more channels, or with empty/skipped (AV_CHAN_SILENCE)
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|      * channels at arbitrary positions.
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|      */
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|     AV_CHANNEL_ORDER_CUSTOM,
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|     /**
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|      * The audio is represented as the decomposition of the sound field into
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|      * spherical harmonics. Each channel corresponds to a single expansion
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|      * component. Channels are ordered according to ACN (Ambisonic Channel
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|      * Number).
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|      *
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|      * The channel with the index n in the stream contains the spherical
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|      * harmonic of degree l and order m given by
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|      * @code{.unparsed}
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|      *   l   = floor(sqrt(n)),
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|      *   m   = n - l * (l + 1).
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|      * @endcode
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|      *
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|      * Conversely given a spherical harmonic of degree l and order m, the
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|      * corresponding channel index n is given by
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|      * @code{.unparsed}
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|      *   n = l * (l + 1) + m.
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|      * @endcode
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|      *
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|      * Normalization is assumed to be SN3D (Schmidt Semi-Normalization)
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|      * as defined in AmbiX format $ 2.1.
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|      */
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|     AV_CHANNEL_ORDER_AMBISONIC,
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| };
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| 
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| 
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| /**
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|  * @defgroup channel_masks Audio channel masks
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|  *
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|  * A channel layout is a 64-bits integer with a bit set for every channel.
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|  * The number of bits set must be equal to the number of channels.
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|  * The value 0 means that the channel layout is not known.
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|  * @note this data structure is not powerful enough to handle channels
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|  * combinations that have the same channel multiple times, such as
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|  * dual-mono.
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|  *
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|  * @{
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|  */
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| #define AV_CH_FRONT_LEFT             (1ULL << AV_CHAN_FRONT_LEFT           )
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| #define AV_CH_FRONT_RIGHT            (1ULL << AV_CHAN_FRONT_RIGHT          )
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| #define AV_CH_FRONT_CENTER           (1ULL << AV_CHAN_FRONT_CENTER         )
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| #define AV_CH_LOW_FREQUENCY          (1ULL << AV_CHAN_LOW_FREQUENCY        )
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| #define AV_CH_BACK_LEFT              (1ULL << AV_CHAN_BACK_LEFT            )
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| #define AV_CH_BACK_RIGHT             (1ULL << AV_CHAN_BACK_RIGHT           )
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| #define AV_CH_FRONT_LEFT_OF_CENTER   (1ULL << AV_CHAN_FRONT_LEFT_OF_CENTER )
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| #define AV_CH_FRONT_RIGHT_OF_CENTER  (1ULL << AV_CHAN_FRONT_RIGHT_OF_CENTER)
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| #define AV_CH_BACK_CENTER            (1ULL << AV_CHAN_BACK_CENTER          )
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| #define AV_CH_SIDE_LEFT              (1ULL << AV_CHAN_SIDE_LEFT            )
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| #define AV_CH_SIDE_RIGHT             (1ULL << AV_CHAN_SIDE_RIGHT           )
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| #define AV_CH_TOP_CENTER             (1ULL << AV_CHAN_TOP_CENTER           )
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| #define AV_CH_TOP_FRONT_LEFT         (1ULL << AV_CHAN_TOP_FRONT_LEFT       )
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| #define AV_CH_TOP_FRONT_CENTER       (1ULL << AV_CHAN_TOP_FRONT_CENTER     )
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| #define AV_CH_TOP_FRONT_RIGHT        (1ULL << AV_CHAN_TOP_FRONT_RIGHT      )
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| #define AV_CH_TOP_BACK_LEFT          (1ULL << AV_CHAN_TOP_BACK_LEFT        )
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| #define AV_CH_TOP_BACK_CENTER        (1ULL << AV_CHAN_TOP_BACK_CENTER      )
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| #define AV_CH_TOP_BACK_RIGHT         (1ULL << AV_CHAN_TOP_BACK_RIGHT       )
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| #define AV_CH_STEREO_LEFT            (1ULL << AV_CHAN_STEREO_LEFT          )
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| #define AV_CH_STEREO_RIGHT           (1ULL << AV_CHAN_STEREO_RIGHT         )
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| #define AV_CH_WIDE_LEFT              (1ULL << AV_CHAN_WIDE_LEFT            )
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| #define AV_CH_WIDE_RIGHT             (1ULL << AV_CHAN_WIDE_RIGHT           )
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| #define AV_CH_SURROUND_DIRECT_LEFT   (1ULL << AV_CHAN_SURROUND_DIRECT_LEFT )
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| #define AV_CH_SURROUND_DIRECT_RIGHT  (1ULL << AV_CHAN_SURROUND_DIRECT_RIGHT)
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| #define AV_CH_LOW_FREQUENCY_2        (1ULL << AV_CHAN_LOW_FREQUENCY_2      )
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| #define AV_CH_TOP_SIDE_LEFT          (1ULL << AV_CHAN_TOP_SIDE_LEFT        )
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| #define AV_CH_TOP_SIDE_RIGHT         (1ULL << AV_CHAN_TOP_SIDE_RIGHT       )
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| #define AV_CH_BOTTOM_FRONT_CENTER    (1ULL << AV_CHAN_BOTTOM_FRONT_CENTER  )
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| #define AV_CH_BOTTOM_FRONT_LEFT      (1ULL << AV_CHAN_BOTTOM_FRONT_LEFT    )
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| #define AV_CH_BOTTOM_FRONT_RIGHT     (1ULL << AV_CHAN_BOTTOM_FRONT_RIGHT   )
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| 
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| #if FF_API_OLD_CHANNEL_LAYOUT
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| /** Channel mask value used for AVCodecContext.request_channel_layout
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|     to indicate that the user requests the channel order of the decoder output
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|     to be the native codec channel order.
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|     @deprecated channel order is now indicated in a special field in
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|                 AVChannelLayout
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|     */
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| #define AV_CH_LAYOUT_NATIVE          0x8000000000000000ULL
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| #endif
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| 
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| /**
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|  * @}
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|  * @defgroup channel_mask_c Audio channel layouts
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|  * @{
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|  * */
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| #define AV_CH_LAYOUT_MONO              (AV_CH_FRONT_CENTER)
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| #define AV_CH_LAYOUT_STEREO            (AV_CH_FRONT_LEFT|AV_CH_FRONT_RIGHT)
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| #define AV_CH_LAYOUT_2POINT1           (AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY)
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| #define AV_CH_LAYOUT_2_1               (AV_CH_LAYOUT_STEREO|AV_CH_BACK_CENTER)
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| #define AV_CH_LAYOUT_SURROUND          (AV_CH_LAYOUT_STEREO|AV_CH_FRONT_CENTER)
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| #define AV_CH_LAYOUT_3POINT1           (AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY)
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| #define AV_CH_LAYOUT_4POINT0           (AV_CH_LAYOUT_SURROUND|AV_CH_BACK_CENTER)
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| #define AV_CH_LAYOUT_4POINT1           (AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY)
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| #define AV_CH_LAYOUT_2_2               (AV_CH_LAYOUT_STEREO|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT)
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| #define AV_CH_LAYOUT_QUAD              (AV_CH_LAYOUT_STEREO|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
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| #define AV_CH_LAYOUT_5POINT0           (AV_CH_LAYOUT_SURROUND|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT)
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| #define AV_CH_LAYOUT_5POINT1           (AV_CH_LAYOUT_5POINT0|AV_CH_LOW_FREQUENCY)
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| #define AV_CH_LAYOUT_5POINT0_BACK      (AV_CH_LAYOUT_SURROUND|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
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| #define AV_CH_LAYOUT_5POINT1_BACK      (AV_CH_LAYOUT_5POINT0_BACK|AV_CH_LOW_FREQUENCY)
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| #define AV_CH_LAYOUT_6POINT0           (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_CENTER)
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| #define AV_CH_LAYOUT_6POINT0_FRONT     (AV_CH_LAYOUT_2_2|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
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| #define AV_CH_LAYOUT_HEXAGONAL         (AV_CH_LAYOUT_5POINT0_BACK|AV_CH_BACK_CENTER)
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| #define AV_CH_LAYOUT_6POINT1           (AV_CH_LAYOUT_5POINT1|AV_CH_BACK_CENTER)
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| #define AV_CH_LAYOUT_6POINT1_BACK      (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_BACK_CENTER)
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| #define AV_CH_LAYOUT_6POINT1_FRONT     (AV_CH_LAYOUT_6POINT0_FRONT|AV_CH_LOW_FREQUENCY)
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| #define AV_CH_LAYOUT_7POINT0           (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
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| #define AV_CH_LAYOUT_7POINT0_FRONT     (AV_CH_LAYOUT_5POINT0|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
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| #define AV_CH_LAYOUT_7POINT1           (AV_CH_LAYOUT_5POINT1|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
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| #define AV_CH_LAYOUT_7POINT1_WIDE      (AV_CH_LAYOUT_5POINT1|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
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| #define AV_CH_LAYOUT_7POINT1_WIDE_BACK (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
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| #define AV_CH_LAYOUT_5POINT1POINT2_BACK (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT)
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| #define AV_CH_LAYOUT_OCTAGONAL         (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_LEFT|AV_CH_BACK_CENTER|AV_CH_BACK_RIGHT)
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| #define AV_CH_LAYOUT_CUBE              (AV_CH_LAYOUT_QUAD|AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT|AV_CH_TOP_BACK_LEFT|AV_CH_TOP_BACK_RIGHT)
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| #define AV_CH_LAYOUT_5POINT1POINT4_BACK (AV_CH_LAYOUT_5POINT1POINT2_BACK|AV_CH_TOP_BACK_LEFT|AV_CH_TOP_BACK_RIGHT)
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| #define AV_CH_LAYOUT_7POINT1POINT2     (AV_CH_LAYOUT_7POINT1|AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT)
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| #define AV_CH_LAYOUT_7POINT1POINT4_BACK (AV_CH_LAYOUT_7POINT1POINT2|AV_CH_TOP_BACK_LEFT|AV_CH_TOP_BACK_RIGHT)
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| #define AV_CH_LAYOUT_HEXADECAGONAL     (AV_CH_LAYOUT_OCTAGONAL|AV_CH_WIDE_LEFT|AV_CH_WIDE_RIGHT|AV_CH_TOP_BACK_LEFT|AV_CH_TOP_BACK_RIGHT|AV_CH_TOP_BACK_CENTER|AV_CH_TOP_FRONT_CENTER|AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT)
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| #define AV_CH_LAYOUT_STEREO_DOWNMIX    (AV_CH_STEREO_LEFT|AV_CH_STEREO_RIGHT)
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| #define AV_CH_LAYOUT_22POINT2          (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER|AV_CH_BACK_CENTER|AV_CH_LOW_FREQUENCY_2|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT|AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT|AV_CH_TOP_FRONT_CENTER|AV_CH_TOP_CENTER|AV_CH_TOP_BACK_LEFT|AV_CH_TOP_BACK_RIGHT|AV_CH_TOP_SIDE_LEFT|AV_CH_TOP_SIDE_RIGHT|AV_CH_TOP_BACK_CENTER|AV_CH_BOTTOM_FRONT_CENTER|AV_CH_BOTTOM_FRONT_LEFT|AV_CH_BOTTOM_FRONT_RIGHT)
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| 
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| #define AV_CH_LAYOUT_7POINT1_TOP_BACK AV_CH_LAYOUT_5POINT1POINT2_BACK
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| 
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| enum AVMatrixEncoding {
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|     AV_MATRIX_ENCODING_NONE,
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|     AV_MATRIX_ENCODING_DOLBY,
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|     AV_MATRIX_ENCODING_DPLII,
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|     AV_MATRIX_ENCODING_DPLIIX,
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|     AV_MATRIX_ENCODING_DPLIIZ,
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|     AV_MATRIX_ENCODING_DOLBYEX,
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|     AV_MATRIX_ENCODING_DOLBYHEADPHONE,
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|     AV_MATRIX_ENCODING_NB
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| };
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| 
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| /**
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|  * @}
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|  */
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| 
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| /**
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|  * An AVChannelCustom defines a single channel within a custom order layout
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|  *
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|  * Unlike most structures in FFmpeg, sizeof(AVChannelCustom) is a part of the
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|  * public ABI.
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|  *
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|  * No new fields may be added to it without a major version bump.
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|  */
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| typedef struct AVChannelCustom {
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|     enum AVChannel id;
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|     char name[16];
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|     void *opaque;
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| } AVChannelCustom;
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| 
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| /**
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|  * An AVChannelLayout holds information about the channel layout of audio data.
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|  *
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|  * A channel layout here is defined as a set of channels ordered in a specific
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|  * way (unless the channel order is AV_CHANNEL_ORDER_UNSPEC, in which case an
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|  * AVChannelLayout carries only the channel count).
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|  * All orders may be treated as if they were AV_CHANNEL_ORDER_UNSPEC by
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|  * ignoring everything but the channel count, as long as av_channel_layout_check()
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|  * considers they are valid.
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|  *
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|  * Unlike most structures in FFmpeg, sizeof(AVChannelLayout) is a part of the
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|  * public ABI and may be used by the caller. E.g. it may be allocated on stack
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|  * or embedded in caller-defined structs.
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|  *
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|  * AVChannelLayout can be initialized as follows:
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|  * - default initialization with {0}, followed by setting all used fields
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|  *   correctly;
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|  * - by assigning one of the predefined AV_CHANNEL_LAYOUT_* initializers;
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|  * - with a constructor function, such as av_channel_layout_default(),
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|  *   av_channel_layout_from_mask() or av_channel_layout_from_string().
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|  *
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|  * The channel layout must be unitialized with av_channel_layout_uninit()
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|  *
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|  * Copying an AVChannelLayout via assigning is forbidden,
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|  * av_channel_layout_copy() must be used instead (and its return value should
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|  * be checked)
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|  *
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|  * No new fields may be added to it without a major version bump, except for
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|  * new elements of the union fitting in sizeof(uint64_t).
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|  */
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| typedef struct AVChannelLayout {
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|     /**
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|      * Channel order used in this layout.
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|      * This is a mandatory field.
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|      */
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|     enum AVChannelOrder order;
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| 
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|     /**
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|      * Number of channels in this layout. Mandatory field.
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|      */
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|     int nb_channels;
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| 
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|     /**
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|      * Details about which channels are present in this layout.
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|      * For AV_CHANNEL_ORDER_UNSPEC, this field is undefined and must not be
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|      * used.
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|      */
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|     union {
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|         /**
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|          * This member must be used for AV_CHANNEL_ORDER_NATIVE, and may be used
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|          * for AV_CHANNEL_ORDER_AMBISONIC to signal non-diegetic channels.
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|          * It is a bitmask, where the position of each set bit means that the
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|          * AVChannel with the corresponding value is present.
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|          *
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|          * I.e. when (mask & (1 << AV_CHAN_FOO)) is non-zero, then AV_CHAN_FOO
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|          * is present in the layout. Otherwise it is not present.
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|          *
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|          * @note when a channel layout using a bitmask is constructed or
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|          * modified manually (i.e.  not using any of the av_channel_layout_*
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|          * functions), the code doing it must ensure that the number of set bits
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|          * is equal to nb_channels.
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|          */
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|         uint64_t mask;
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|         /**
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|          * This member must be used when the channel order is
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|          * AV_CHANNEL_ORDER_CUSTOM. It is a nb_channels-sized array, with each
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|          * element signalling the presence of the AVChannel with the
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|          * corresponding value in map[i].id.
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|          *
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|          * I.e. when map[i].id is equal to AV_CHAN_FOO, then AV_CH_FOO is the
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|          * i-th channel in the audio data.
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|          *
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|          * When map[i].id is in the range between AV_CHAN_AMBISONIC_BASE and
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|          * AV_CHAN_AMBISONIC_END (inclusive), the channel contains an ambisonic
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|          * component with ACN index (as defined above)
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|          * n = map[i].id - AV_CHAN_AMBISONIC_BASE.
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|          *
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|          * map[i].name may be filled with a 0-terminated string, in which case
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|          * it will be used for the purpose of identifying the channel with the
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|          * convenience functions below. Otherise it must be zeroed.
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|          */
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|         AVChannelCustom *map;
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|     } u;
 | |
| 
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|     /**
 | |
|      * For some private data of the user.
 | |
|      */
 | |
|     void *opaque;
 | |
| } AVChannelLayout;
 | |
| 
 | |
| /**
 | |
|  * Macro to define native channel layouts
 | |
|  *
 | |
|  * @note This doesn't use designated initializers for compatibility with C++ 17 and older.
 | |
|  */
 | |
| #define AV_CHANNEL_LAYOUT_MASK(nb, m) \
 | |
|     { /* .order */ AV_CHANNEL_ORDER_NATIVE, \
 | |
|       /* .nb_channels */  (nb), \
 | |
|       /* .u.mask */ { m }, \
 | |
|       /* .opaque */ NULL }
 | |
| 
 | |
| /**
 | |
|  * @name Common pre-defined channel layouts
 | |
|  * @{
 | |
|  */
 | |
| #define AV_CHANNEL_LAYOUT_MONO              AV_CHANNEL_LAYOUT_MASK(1,  AV_CH_LAYOUT_MONO)
 | |
| #define AV_CHANNEL_LAYOUT_STEREO            AV_CHANNEL_LAYOUT_MASK(2,  AV_CH_LAYOUT_STEREO)
 | |
| #define AV_CHANNEL_LAYOUT_2POINT1           AV_CHANNEL_LAYOUT_MASK(3,  AV_CH_LAYOUT_2POINT1)
 | |
| #define AV_CHANNEL_LAYOUT_2_1               AV_CHANNEL_LAYOUT_MASK(3,  AV_CH_LAYOUT_2_1)
 | |
| #define AV_CHANNEL_LAYOUT_SURROUND          AV_CHANNEL_LAYOUT_MASK(3,  AV_CH_LAYOUT_SURROUND)
 | |
| #define AV_CHANNEL_LAYOUT_3POINT1           AV_CHANNEL_LAYOUT_MASK(4,  AV_CH_LAYOUT_3POINT1)
 | |
| #define AV_CHANNEL_LAYOUT_4POINT0           AV_CHANNEL_LAYOUT_MASK(4,  AV_CH_LAYOUT_4POINT0)
 | |
| #define AV_CHANNEL_LAYOUT_4POINT1           AV_CHANNEL_LAYOUT_MASK(5,  AV_CH_LAYOUT_4POINT1)
 | |
| #define AV_CHANNEL_LAYOUT_2_2               AV_CHANNEL_LAYOUT_MASK(4,  AV_CH_LAYOUT_2_2)
 | |
| #define AV_CHANNEL_LAYOUT_QUAD              AV_CHANNEL_LAYOUT_MASK(4,  AV_CH_LAYOUT_QUAD)
 | |
| #define AV_CHANNEL_LAYOUT_5POINT0           AV_CHANNEL_LAYOUT_MASK(5,  AV_CH_LAYOUT_5POINT0)
 | |
| #define AV_CHANNEL_LAYOUT_5POINT1           AV_CHANNEL_LAYOUT_MASK(6,  AV_CH_LAYOUT_5POINT1)
 | |
| #define AV_CHANNEL_LAYOUT_5POINT0_BACK      AV_CHANNEL_LAYOUT_MASK(5,  AV_CH_LAYOUT_5POINT0_BACK)
 | |
| #define AV_CHANNEL_LAYOUT_5POINT1_BACK      AV_CHANNEL_LAYOUT_MASK(6,  AV_CH_LAYOUT_5POINT1_BACK)
 | |
| #define AV_CHANNEL_LAYOUT_6POINT0           AV_CHANNEL_LAYOUT_MASK(6,  AV_CH_LAYOUT_6POINT0)
 | |
| #define AV_CHANNEL_LAYOUT_6POINT0_FRONT     AV_CHANNEL_LAYOUT_MASK(6,  AV_CH_LAYOUT_6POINT0_FRONT)
 | |
| #define AV_CHANNEL_LAYOUT_HEXAGONAL         AV_CHANNEL_LAYOUT_MASK(6,  AV_CH_LAYOUT_HEXAGONAL)
 | |
| #define AV_CHANNEL_LAYOUT_6POINT1           AV_CHANNEL_LAYOUT_MASK(7,  AV_CH_LAYOUT_6POINT1)
 | |
| #define AV_CHANNEL_LAYOUT_6POINT1_BACK      AV_CHANNEL_LAYOUT_MASK(7,  AV_CH_LAYOUT_6POINT1_BACK)
 | |
| #define AV_CHANNEL_LAYOUT_6POINT1_FRONT     AV_CHANNEL_LAYOUT_MASK(7,  AV_CH_LAYOUT_6POINT1_FRONT)
 | |
| #define AV_CHANNEL_LAYOUT_7POINT0           AV_CHANNEL_LAYOUT_MASK(7,  AV_CH_LAYOUT_7POINT0)
 | |
| #define AV_CHANNEL_LAYOUT_7POINT0_FRONT     AV_CHANNEL_LAYOUT_MASK(7,  AV_CH_LAYOUT_7POINT0_FRONT)
 | |
| #define AV_CHANNEL_LAYOUT_7POINT1           AV_CHANNEL_LAYOUT_MASK(8,  AV_CH_LAYOUT_7POINT1)
 | |
| #define AV_CHANNEL_LAYOUT_7POINT1_WIDE      AV_CHANNEL_LAYOUT_MASK(8,  AV_CH_LAYOUT_7POINT1_WIDE)
 | |
| #define AV_CHANNEL_LAYOUT_7POINT1_WIDE_BACK AV_CHANNEL_LAYOUT_MASK(8,  AV_CH_LAYOUT_7POINT1_WIDE_BACK)
 | |
| #define AV_CHANNEL_LAYOUT_5POINT1POINT2_BACK AV_CHANNEL_LAYOUT_MASK(8, AV_CH_LAYOUT_5POINT1POINT2_BACK)
 | |
| #define AV_CHANNEL_LAYOUT_OCTAGONAL         AV_CHANNEL_LAYOUT_MASK(8,  AV_CH_LAYOUT_OCTAGONAL)
 | |
| #define AV_CHANNEL_LAYOUT_CUBE              AV_CHANNEL_LAYOUT_MASK(8,  AV_CH_LAYOUT_CUBE)
 | |
| #define AV_CHANNEL_LAYOUT_5POINT1POINT4_BACK AV_CHANNEL_LAYOUT_MASK(10, AV_CH_LAYOUT_5POINT1POINT4_BACK)
 | |
| #define AV_CHANNEL_LAYOUT_7POINT1POINT2     AV_CHANNEL_LAYOUT_MASK(10, AV_CH_LAYOUT_7POINT1POINT2)
 | |
| #define AV_CHANNEL_LAYOUT_7POINT1POINT4_BACK AV_CHANNEL_LAYOUT_MASK(12, AV_CH_LAYOUT_7POINT1POINT4_BACK)
 | |
| #define AV_CHANNEL_LAYOUT_HEXADECAGONAL     AV_CHANNEL_LAYOUT_MASK(16, AV_CH_LAYOUT_HEXADECAGONAL)
 | |
| #define AV_CHANNEL_LAYOUT_STEREO_DOWNMIX    AV_CHANNEL_LAYOUT_MASK(2,  AV_CH_LAYOUT_STEREO_DOWNMIX)
 | |
| #define AV_CHANNEL_LAYOUT_22POINT2          AV_CHANNEL_LAYOUT_MASK(24, AV_CH_LAYOUT_22POINT2)
 | |
| 
 | |
| #define AV_CHANNEL_LAYOUT_7POINT1_TOP_BACK  AV_CHANNEL_LAYOUT_5POINT1POINT2_BACK
 | |
| 
 | |
| #define AV_CHANNEL_LAYOUT_AMBISONIC_FIRST_ORDER \
 | |
|     { /* .order */ AV_CHANNEL_ORDER_AMBISONIC, \
 | |
|       /* .nb_channels */ 4, \
 | |
|       /* .u.mask */ { 0 }, \
 | |
|       /* .opaque */ NULL }
 | |
| /** @} */
 | |
| 
 | |
| struct AVBPrint;
 | |
| 
 | |
| #if FF_API_OLD_CHANNEL_LAYOUT
 | |
| /**
 | |
|  * @name Deprecated Functions
 | |
|  * @{
 | |
|  */
 | |
| 
 | |
| /**
 | |
|  * Return a channel layout id that matches name, or 0 if no match is found.
 | |
|  *
 | |
|  * name can be one or several of the following notations,
 | |
|  * separated by '+' or '|':
 | |
|  * - the name of an usual channel layout (mono, stereo, 4.0, quad, 5.0,
 | |
|  *   5.0(side), 5.1, 5.1(side), 7.1, 7.1(wide), downmix);
 | |
|  * - the name of a single channel (FL, FR, FC, LFE, BL, BR, FLC, FRC, BC,
 | |
|  *   SL, SR, TC, TFL, TFC, TFR, TBL, TBC, TBR, DL, DR);
 | |
|  * - a number of channels, in decimal, followed by 'c', yielding
 | |
|  *   the default channel layout for that number of channels (@see
 | |
|  *   av_get_default_channel_layout);
 | |
|  * - a channel layout mask, in hexadecimal starting with "0x" (see the
 | |
|  *   AV_CH_* macros).
 | |
|  *
 | |
|  * Example: "stereo+FC" = "2c+FC" = "2c+1c" = "0x7"
 | |
|  *
 | |
|  * @deprecated use av_channel_layout_from_string()
 | |
|  */
 | |
| attribute_deprecated
 | |
| uint64_t av_get_channel_layout(const char *name);
 | |
| 
 | |
| /**
 | |
|  * Return a channel layout and the number of channels based on the specified name.
 | |
|  *
 | |
|  * This function is similar to (@see av_get_channel_layout), but can also parse
 | |
|  * unknown channel layout specifications.
 | |
|  *
 | |
|  * @param[in]  name             channel layout specification string
 | |
|  * @param[out] channel_layout   parsed channel layout (0 if unknown)
 | |
|  * @param[out] nb_channels      number of channels
 | |
|  *
 | |
|  * @return 0 on success, AVERROR(EINVAL) if the parsing fails.
 | |
|  * @deprecated use av_channel_layout_from_string()
 | |
|  */
 | |
| attribute_deprecated
 | |
| int av_get_extended_channel_layout(const char *name, uint64_t* channel_layout, int* nb_channels);
 | |
| 
 | |
| /**
 | |
|  * Return a description of a channel layout.
 | |
|  * If nb_channels is <= 0, it is guessed from the channel_layout.
 | |
|  *
 | |
|  * @param buf put here the string containing the channel layout
 | |
|  * @param buf_size size in bytes of the buffer
 | |
|  * @param nb_channels number of channels
 | |
|  * @param channel_layout channel layout bitset
 | |
|  * @deprecated use av_channel_layout_describe()
 | |
|  */
 | |
| attribute_deprecated
 | |
| void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout);
 | |
| 
 | |
| /**
 | |
|  * Append a description of a channel layout to a bprint buffer.
 | |
|  * @deprecated use av_channel_layout_describe()
 | |
|  */
 | |
| attribute_deprecated
 | |
| void av_bprint_channel_layout(struct AVBPrint *bp, int nb_channels, uint64_t channel_layout);
 | |
| 
 | |
| /**
 | |
|  * Return the number of channels in the channel layout.
 | |
|  * @deprecated use AVChannelLayout.nb_channels
 | |
|  */
 | |
| attribute_deprecated
 | |
| int av_get_channel_layout_nb_channels(uint64_t channel_layout);
 | |
| 
 | |
| /**
 | |
|  * Return default channel layout for a given number of channels.
 | |
|  *
 | |
|  * @deprecated use av_channel_layout_default()
 | |
|  */
 | |
| attribute_deprecated
 | |
| int64_t av_get_default_channel_layout(int nb_channels);
 | |
| 
 | |
| /**
 | |
|  * Get the index of a channel in channel_layout.
 | |
|  *
 | |
|  * @param channel_layout channel layout bitset
 | |
|  * @param channel a channel layout describing exactly one channel which must be
 | |
|  *                present in channel_layout.
 | |
|  *
 | |
|  * @return index of channel in channel_layout on success, a negative AVERROR
 | |
|  *         on error.
 | |
|  *
 | |
|  * @deprecated use av_channel_layout_index_from_channel()
 | |
|  */
 | |
| attribute_deprecated
 | |
| int av_get_channel_layout_channel_index(uint64_t channel_layout,
 | |
|                                         uint64_t channel);
 | |
| 
 | |
| /**
 | |
|  * Get the channel with the given index in channel_layout.
 | |
|  * @deprecated use av_channel_layout_channel_from_index()
 | |
|  */
 | |
| attribute_deprecated
 | |
| uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index);
 | |
| 
 | |
| /**
 | |
|  * Get the name of a given channel.
 | |
|  *
 | |
|  * @return channel name on success, NULL on error.
 | |
|  *
 | |
|  * @deprecated use av_channel_name()
 | |
|  */
 | |
| attribute_deprecated
 | |
| const char *av_get_channel_name(uint64_t channel);
 | |
| 
 | |
| /**
 | |
|  * Get the description of a given channel.
 | |
|  *
 | |
|  * @param channel  a channel layout with a single channel
 | |
|  * @return  channel description on success, NULL on error
 | |
|  * @deprecated use av_channel_description()
 | |
|  */
 | |
| attribute_deprecated
 | |
| const char *av_get_channel_description(uint64_t channel);
 | |
| 
 | |
| /**
 | |
|  * Get the value and name of a standard channel layout.
 | |
|  *
 | |
|  * @param[in]  index   index in an internal list, starting at 0
 | |
|  * @param[out] layout  channel layout mask
 | |
|  * @param[out] name    name of the layout
 | |
|  * @return  0  if the layout exists,
 | |
|  *          <0 if index is beyond the limits
 | |
|  * @deprecated use av_channel_layout_standard()
 | |
|  */
 | |
| attribute_deprecated
 | |
| int av_get_standard_channel_layout(unsigned index, uint64_t *layout,
 | |
|                                    const char **name);
 | |
| /**
 | |
|  * @}
 | |
|  */
 | |
| #endif
 | |
| 
 | |
| /**
 | |
|  * Get a human readable string in an abbreviated form describing a given channel.
 | |
|  * This is the inverse function of @ref av_channel_from_string().
 | |
|  *
 | |
|  * @param buf pre-allocated buffer where to put the generated string
 | |
|  * @param buf_size size in bytes of the buffer.
 | |
|  * @param channel the AVChannel whose name to get
 | |
|  * @return amount of bytes needed to hold the output string, or a negative AVERROR
 | |
|  *         on failure. If the returned value is bigger than buf_size, then the
 | |
|  *         string was truncated.
 | |
|  */
 | |
| int av_channel_name(char *buf, size_t buf_size, enum AVChannel channel);
 | |
| 
 | |
| /**
 | |
|  * bprint variant of av_channel_name().
 | |
|  *
 | |
|  * @note the string will be appended to the bprint buffer.
 | |
|  */
 | |
| void av_channel_name_bprint(struct AVBPrint *bp, enum AVChannel channel_id);
 | |
| 
 | |
| /**
 | |
|  * Get a human readable string describing a given channel.
 | |
|  *
 | |
|  * @param buf pre-allocated buffer where to put the generated string
 | |
|  * @param buf_size size in bytes of the buffer.
 | |
|  * @param channel the AVChannel whose description to get
 | |
|  * @return amount of bytes needed to hold the output string, or a negative AVERROR
 | |
|  *         on failure. If the returned value is bigger than buf_size, then the
 | |
|  *         string was truncated.
 | |
|  */
 | |
| int av_channel_description(char *buf, size_t buf_size, enum AVChannel channel);
 | |
| 
 | |
| /**
 | |
|  * bprint variant of av_channel_description().
 | |
|  *
 | |
|  * @note the string will be appended to the bprint buffer.
 | |
|  */
 | |
| void av_channel_description_bprint(struct AVBPrint *bp, enum AVChannel channel_id);
 | |
| 
 | |
| /**
 | |
|  * This is the inverse function of @ref av_channel_name().
 | |
|  *
 | |
|  * @return the channel with the given name
 | |
|  *         AV_CHAN_NONE when name does not identify a known channel
 | |
|  */
 | |
| enum AVChannel av_channel_from_string(const char *name);
 | |
| 
 | |
| /**
 | |
|  * Initialize a native channel layout from a bitmask indicating which channels
 | |
|  * are present.
 | |
|  *
 | |
|  * @param channel_layout the layout structure to be initialized
 | |
|  * @param mask bitmask describing the channel layout
 | |
|  *
 | |
|  * @return 0 on success
 | |
|  *         AVERROR(EINVAL) for invalid mask values
 | |
|  */
 | |
| int av_channel_layout_from_mask(AVChannelLayout *channel_layout, uint64_t mask);
 | |
| 
 | |
| /**
 | |
|  * Initialize a channel layout from a given string description.
 | |
|  * The input string can be represented by:
 | |
|  *  - the formal channel layout name (returned by av_channel_layout_describe())
 | |
|  *  - single or multiple channel names (returned by av_channel_name(), eg. "FL",
 | |
|  *    or concatenated with "+", each optionally containing a custom name after
 | |
|  *    a "@", eg. "FL@Left+FR@Right+LFE")
 | |
|  *  - a decimal or hexadecimal value of a native channel layout (eg. "4" or "0x4")
 | |
|  *  - the number of channels with default layout (eg. "4c")
 | |
|  *  - the number of unordered channels (eg. "4C" or "4 channels")
 | |
|  *  - the ambisonic order followed by optional non-diegetic channels (eg.
 | |
|  *    "ambisonic 2+stereo")
 | |
|  *
 | |
|  * @param channel_layout input channel layout
 | |
|  * @param str string describing the channel layout
 | |
|  * @return 0 channel layout was detected, AVERROR_INVALIDATATA otherwise
 | |
|  */
 | |
| int av_channel_layout_from_string(AVChannelLayout *channel_layout,
 | |
|                                   const char *str);
 | |
| 
 | |
| /**
 | |
|  * Get the default channel layout for a given number of channels.
 | |
|  *
 | |
|  * @param ch_layout the layout structure to be initialized
 | |
|  * @param nb_channels number of channels
 | |
|  */
 | |
| void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels);
 | |
| 
 | |
| /**
 | |
|  * Iterate over all standard channel layouts.
 | |
|  *
 | |
|  * @param opaque a pointer where libavutil will store the iteration state. Must
 | |
|  *               point to NULL to start the iteration.
 | |
|  *
 | |
|  * @return the standard channel layout or NULL when the iteration is
 | |
|  *         finished
 | |
|  */
 | |
| const AVChannelLayout *av_channel_layout_standard(void **opaque);
 | |
| 
 | |
| /**
 | |
|  * Free any allocated data in the channel layout and reset the channel
 | |
|  * count to 0.
 | |
|  *
 | |
|  * @param channel_layout the layout structure to be uninitialized
 | |
|  */
 | |
| void av_channel_layout_uninit(AVChannelLayout *channel_layout);
 | |
| 
 | |
| /**
 | |
|  * Make a copy of a channel layout. This differs from just assigning src to dst
 | |
|  * in that it allocates and copies the map for AV_CHANNEL_ORDER_CUSTOM.
 | |
|  *
 | |
|  * @note the destination channel_layout will be always uninitialized before copy.
 | |
|  *
 | |
|  * @param dst destination channel layout
 | |
|  * @param src source channel layout
 | |
|  * @return 0 on success, a negative AVERROR on error.
 | |
|  */
 | |
| int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src);
 | |
| 
 | |
| /**
 | |
|  * Get a human-readable string describing the channel layout properties.
 | |
|  * The string will be in the same format that is accepted by
 | |
|  * @ref av_channel_layout_from_string(), allowing to rebuild the same
 | |
|  * channel layout, except for opaque pointers.
 | |
|  *
 | |
|  * @param channel_layout channel layout to be described
 | |
|  * @param buf pre-allocated buffer where to put the generated string
 | |
|  * @param buf_size size in bytes of the buffer.
 | |
|  * @return amount of bytes needed to hold the output string, or a negative AVERROR
 | |
|  *         on failure. If the returned value is bigger than buf_size, then the
 | |
|  *         string was truncated.
 | |
|  */
 | |
| int av_channel_layout_describe(const AVChannelLayout *channel_layout,
 | |
|                                char *buf, size_t buf_size);
 | |
| 
 | |
| /**
 | |
|  * bprint variant of av_channel_layout_describe().
 | |
|  *
 | |
|  * @note the string will be appended to the bprint buffer.
 | |
|  * @return 0 on success, or a negative AVERROR value on failure.
 | |
|  */
 | |
| int av_channel_layout_describe_bprint(const AVChannelLayout *channel_layout,
 | |
|                                       struct AVBPrint *bp);
 | |
| 
 | |
| /**
 | |
|  * Get the channel with the given index in a channel layout.
 | |
|  *
 | |
|  * @param channel_layout input channel layout
 | |
|  * @param idx index of the channel
 | |
|  * @return channel with the index idx in channel_layout on success or
 | |
|  *         AV_CHAN_NONE on failure (if idx is not valid or the channel order is
 | |
|  *         unspecified)
 | |
|  */
 | |
| enum AVChannel
 | |
| av_channel_layout_channel_from_index(const AVChannelLayout *channel_layout, unsigned int idx);
 | |
| 
 | |
| /**
 | |
|  * Get the index of a given channel in a channel layout. In case multiple
 | |
|  * channels are found, only the first match will be returned.
 | |
|  *
 | |
|  * @param channel_layout input channel layout
 | |
|  * @param channel the channel whose index to obtain
 | |
|  * @return index of channel in channel_layout on success or a negative number if
 | |
|  *         channel is not present in channel_layout.
 | |
|  */
 | |
| int av_channel_layout_index_from_channel(const AVChannelLayout *channel_layout,
 | |
|                                          enum AVChannel channel);
 | |
| 
 | |
| /**
 | |
|  * Get the index in a channel layout of a channel described by the given string.
 | |
|  * In case multiple channels are found, only the first match will be returned.
 | |
|  *
 | |
|  * This function accepts channel names in the same format as
 | |
|  * @ref av_channel_from_string().
 | |
|  *
 | |
|  * @param channel_layout input channel layout
 | |
|  * @param name string describing the channel whose index to obtain
 | |
|  * @return a channel index described by the given string, or a negative AVERROR
 | |
|  *         value.
 | |
|  */
 | |
| int av_channel_layout_index_from_string(const AVChannelLayout *channel_layout,
 | |
|                                         const char *name);
 | |
| 
 | |
| /**
 | |
|  * Get a channel described by the given string.
 | |
|  *
 | |
|  * This function accepts channel names in the same format as
 | |
|  * @ref av_channel_from_string().
 | |
|  *
 | |
|  * @param channel_layout input channel layout
 | |
|  * @param name string describing the channel to obtain
 | |
|  * @return a channel described by the given string in channel_layout on success
 | |
|  *         or AV_CHAN_NONE on failure (if the string is not valid or the channel
 | |
|  *         order is unspecified)
 | |
|  */
 | |
| enum AVChannel
 | |
| av_channel_layout_channel_from_string(const AVChannelLayout *channel_layout,
 | |
|                                       const char *name);
 | |
| 
 | |
| /**
 | |
|  * Find out what channels from a given set are present in a channel layout,
 | |
|  * without regard for their positions.
 | |
|  *
 | |
|  * @param channel_layout input channel layout
 | |
|  * @param mask a combination of AV_CH_* representing a set of channels
 | |
|  * @return a bitfield representing all the channels from mask that are present
 | |
|  *         in channel_layout
 | |
|  */
 | |
| uint64_t av_channel_layout_subset(const AVChannelLayout *channel_layout,
 | |
|                                   uint64_t mask);
 | |
| 
 | |
| /**
 | |
|  * Check whether a channel layout is valid, i.e. can possibly describe audio
 | |
|  * data.
 | |
|  *
 | |
|  * @param channel_layout input channel layout
 | |
|  * @return 1 if channel_layout is valid, 0 otherwise.
 | |
|  */
 | |
| int av_channel_layout_check(const AVChannelLayout *channel_layout);
 | |
| 
 | |
| /**
 | |
|  * Check whether two channel layouts are semantically the same, i.e. the same
 | |
|  * channels are present on the same positions in both.
 | |
|  *
 | |
|  * If one of the channel layouts is AV_CHANNEL_ORDER_UNSPEC, while the other is
 | |
|  * not, they are considered to be unequal. If both are AV_CHANNEL_ORDER_UNSPEC,
 | |
|  * they are considered equal iff the channel counts are the same in both.
 | |
|  *
 | |
|  * @param chl input channel layout
 | |
|  * @param chl1 input channel layout
 | |
|  * @return 0 if chl and chl1 are equal, 1 if they are not equal. A negative
 | |
|  *         AVERROR code if one or both are invalid.
 | |
|  */
 | |
| int av_channel_layout_compare(const AVChannelLayout *chl, const AVChannelLayout *chl1);
 | |
| 
 | |
| /**
 | |
|  * @}
 | |
|  */
 | |
| 
 | |
| #endif /* AVUTIL_CHANNEL_LAYOUT_H */
 |