FFmpeg
libavcodec
ac3_parser_internal.h
Go to the documentation of this file.
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/*
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* AC-3 parser internal code
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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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#ifndef AVCODEC_AC3_PARSER_INTERNAL_H
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#define AVCODEC_AC3_PARSER_INTERNAL_H
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#include <stddef.h>
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#include <stdint.h>
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#include "
ac3defs.h
"
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#include "
get_bits.h
"
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/**
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* @struct AC3HeaderInfo
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* Coded AC-3 header values up to the lfeon element, plus derived values.
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*/
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typedef
struct
AC3HeaderInfo
{
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/** @name Coded elements
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* @{
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*/
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uint16_t
sync_word
;
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uint16_t
crc1
;
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uint8_t
sr_code
;
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uint8_t
bitstream_id
;
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uint8_t
bitstream_mode
;
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uint8_t
channel_mode
;
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uint8_t
lfe_on
;
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uint8_t
frame_type
;
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int
substreamid
;
///< substream identification
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int
center_mix_level
;
///< Center mix level index
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int
surround_mix_level
;
///< Surround mix level index
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uint16_t
channel_map
;
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int
num_blocks
;
///< number of audio blocks
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int
dolby_surround_mode
;
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/** @} */
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/** @name Derived values
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* @{
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*/
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uint8_t
sr_shift
;
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uint16_t
sample_rate
;
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uint32_t
bit_rate
;
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uint8_t
channels
;
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uint16_t
frame_size
;
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uint64_t
channel_layout
;
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int8_t
ac3_bit_rate_code
;
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/** @} */
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}
AC3HeaderInfo
;
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/**
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* Parse AC-3 frame header.
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* Parse the header up to the lfeon element, which is the first 52 or 54 bits
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* depending on the audio coding mode.
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* @param[in] gbc BitContext containing the first 54 bits of the frame.
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* @param[out] hdr Pointer to struct where header info is written.
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* @return Returns 0 on success, -1 if there is a sync word mismatch,
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* -2 if the bsid (version) element is invalid, -3 if the fscod (sample rate)
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* element is invalid, or -4 if the frmsizecod (bit rate) element is invalid.
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*/
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int
ff_ac3_parse_header
(
GetBitContext
*gbc,
AC3HeaderInfo
*hdr);
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int
avpriv_ac3_parse_header
(
AC3HeaderInfo
**hdr,
const
uint8_t *buf,
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size_t
size
);
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int
ff_ac3_find_syncword
(
const
uint8_t *buf,
int
buf_size);
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#endif
/* AVCODEC_AC3_PARSER_INTERNAL_H */
AC3HeaderInfo::center_mix_level
int center_mix_level
Center mix level index.
Definition:
ac3_parser_internal.h:47
AC3HeaderInfo::frame_type
uint8_t frame_type
Definition:
ac3_parser_internal.h:45
AC3HeaderInfo::dolby_surround_mode
int dolby_surround_mode
Definition:
ac3_parser_internal.h:51
AC3HeaderInfo::channel_layout
uint64_t channel_layout
Definition:
ac3_parser_internal.h:62
GetBitContext
Definition:
get_bits.h:108
AC3HeaderInfo
Definition:
ac3_parser_internal.h:34
AC3HeaderInfo::frame_size
uint16_t frame_size
Definition:
ac3_parser_internal.h:61
AC3HeaderInfo::channel_mode
uint8_t channel_mode
Definition:
ac3_parser_internal.h:43
AC3HeaderInfo::sync_word
uint16_t sync_word
Definition:
ac3_parser_internal.h:38
AC3HeaderInfo::crc1
uint16_t crc1
Definition:
ac3_parser_internal.h:39
get_bits.h
AC3HeaderInfo::sample_rate
uint16_t sample_rate
Definition:
ac3_parser_internal.h:58
ac3defs.h
AC3HeaderInfo::substreamid
int substreamid
substream identification
Definition:
ac3_parser_internal.h:46
AC3HeaderInfo::num_blocks
int num_blocks
number of audio blocks
Definition:
ac3_parser_internal.h:50
AC3HeaderInfo::channels
uint8_t channels
Definition:
ac3_parser_internal.h:60
AC3HeaderInfo::lfe_on
uint8_t lfe_on
Definition:
ac3_parser_internal.h:44
size
int size
Definition:
twinvq_data.h:10344
AC3HeaderInfo::bitstream_mode
uint8_t bitstream_mode
Definition:
ac3_parser_internal.h:42
AC3HeaderInfo::ac3_bit_rate_code
int8_t ac3_bit_rate_code
Definition:
ac3_parser_internal.h:63
ff_ac3_find_syncword
int ff_ac3_find_syncword(const uint8_t *buf, int buf_size)
AC3HeaderInfo::channel_map
uint16_t channel_map
Definition:
ac3_parser_internal.h:49
ff_ac3_parse_header
int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr)
Parse AC-3 frame header.
avpriv_ac3_parse_header
int avpriv_ac3_parse_header(AC3HeaderInfo **hdr, const uint8_t *buf, size_t size)
Definition:
ac3_parser.c:265
AC3HeaderInfo::bitstream_id
uint8_t bitstream_id
Definition:
ac3_parser_internal.h:41
AC3HeaderInfo::sr_shift
uint8_t sr_shift
Definition:
ac3_parser_internal.h:57
AC3HeaderInfo::sr_code
uint8_t sr_code
Definition:
ac3_parser_internal.h:40
AC3HeaderInfo::bit_rate
uint32_t bit_rate
Definition:
ac3_parser_internal.h:59
AC3HeaderInfo::surround_mix_level
int surround_mix_level
Surround mix level index.
Definition:
ac3_parser_internal.h:48
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