FFmpeg
adts_header.h
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1 /*
2  * AAC ADTS header decoding prototypes and structures
3  * Copyright (c) 2003 Fabrice Bellard
4  * Copyright (c) 2003 Michael Niedermayer
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #ifndef AVCODEC_ADTS_HEADER_H
24 #define AVCODEC_ADTS_HEADER_H
25 
26 #include "get_bits.h"
27 
28 typedef struct AACADTSHeaderInfo {
29  uint32_t sample_rate;
30  uint32_t samples;
31  uint32_t bit_rate;
32  uint8_t crc_absent;
33  uint8_t object_type;
34  uint8_t sampling_index;
35  uint8_t chan_config;
36  uint8_t num_aac_frames;
37  uint32_t frame_length;
39 
40 /**
41  * Parse the ADTS frame header to the end of the variable header, which is
42  * the first 54 bits.
43  * @param[in] gbc BitContext containing the first 54 bits of the frame.
44  * @param[out] hdr Pointer to struct where header info is written.
45  * @return Returns 0 on success, -1 if there is a sync word mismatch,
46  * -2 if the version element is invalid, -3 if the sample rate
47  * element is invalid, or -4 if the bit rate element is invalid.
48  */
50 
51 /**
52  * Parse the ADTS frame header contained in the buffer, which is
53  * the first 54 bits.
54  * @param[in] buf Pointer to buffer containing the first 54 bits of the frame.
55  * @param[in] size Size of buffer containing the first 54 bits of the frame.
56  * @param[out] phdr Pointer to pointer to struct AACADTSHeaderInfo for which
57  * memory is allocated and header info is written into it. After using the header
58  * information, the allocated memory must be freed by using av_free.
59  * @return Returns 0 on success, -1 if there is a sync word mismatch,
60  * -2 if the version element is invalid, -3 if the sample rate
61  * element is invalid, or -4 if the bit rate element is invalid.
62  */
63 int avpriv_adts_header_parse(AACADTSHeaderInfo **phdr, const uint8_t *buf, size_t size);
64 
65 #endif /* AVCODEC_ADTS_HEADER_H */
AACADTSHeaderInfo::samples
uint32_t samples
Definition: adts_header.h:30
AACADTSHeaderInfo::bit_rate
uint32_t bit_rate
Definition: adts_header.h:31
GetBitContext
Definition: get_bits.h:107
ff_adts_header_parse
int ff_adts_header_parse(GetBitContext *gbc, AACADTSHeaderInfo *hdr)
Parse the ADTS frame header to the end of the variable header, which is the first 54 bits.
Definition: adts_header.c:30
AACADTSHeaderInfo::chan_config
uint8_t chan_config
Definition: adts_header.h:35
get_bits.h
AACADTSHeaderInfo::num_aac_frames
uint8_t num_aac_frames
Definition: adts_header.h:36
AACADTSHeaderInfo::sampling_index
uint8_t sampling_index
Definition: adts_header.h:34
AACADTSHeaderInfo::frame_length
uint32_t frame_length
Definition: adts_header.h:37
avpriv_adts_header_parse
int avpriv_adts_header_parse(AACADTSHeaderInfo **phdr, const uint8_t *buf, size_t size)
Parse the ADTS frame header contained in the buffer, which is the first 54 bits.
Definition: adts_parser.c:46
size
int size
Definition: twinvq_data.h:10344
AACADTSHeaderInfo::object_type
uint8_t object_type
Definition: adts_header.h:33
AACADTSHeaderInfo::sample_rate
uint32_t sample_rate
Definition: adts_header.h:29
AACADTSHeaderInfo::crc_absent
uint8_t crc_absent
Definition: adts_header.h:32
AACADTSHeaderInfo
Definition: adts_header.h:28