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aac_adtstoasc_bsf.c
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1 /*
2  * MPEG-2/4 AAC ADTS to MPEG-4 Audio Specific Configuration bitstream filter
3  * Copyright (c) 2009 Alex Converse <alex.converse@gmail.com>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "adts_header.h"
23 #include "adts_parser.h"
24 #include "avcodec.h"
25 #include "bsf.h"
26 #include "put_bits.h"
27 #include "get_bits.h"
28 #include "mpeg4audio.h"
29 #include "internal.h"
30 
31 typedef struct AACBSFContext {
34 
35 /**
36  * This filter creates an MPEG-4 AudioSpecificConfig from an MPEG-2/4
37  * ADTS header and removes the ADTS header.
38  */
40 {
41  AACBSFContext *ctx = bsfc->priv_data;
42 
43  GetBitContext gb;
44  PutBitContext pb;
46  int ret;
47 
48  ret = ff_bsf_get_packet_ref(bsfc, pkt);
49  if (ret < 0)
50  return ret;
51 
52  if (bsfc->par_in->extradata && pkt->size >= 2 && (AV_RB16(pkt->data) >> 4) != 0xfff)
53  return 0;
54 
55  if (pkt->size < AV_AAC_ADTS_HEADER_SIZE)
56  goto packet_too_small;
57 
59 
60  if (ff_adts_header_parse(&gb, &hdr) < 0) {
61  av_log(bsfc, AV_LOG_ERROR, "Error parsing ADTS frame header!\n");
62  ret = AVERROR_INVALIDDATA;
63  goto fail;
64  }
65 
66  if (!hdr.crc_absent && hdr.num_aac_frames > 1) {
68  "Multiple RDBs per frame with CRC");
70  goto fail;
71  }
72 
73  pkt->size -= AV_AAC_ADTS_HEADER_SIZE + 2 * !hdr.crc_absent;
74  if (pkt->size <= 0)
75  goto packet_too_small;
76  pkt->data += AV_AAC_ADTS_HEADER_SIZE + 2 * !hdr.crc_absent;
77 
78  if (!ctx->first_frame_done) {
79  int pce_size = 0;
80  uint8_t pce_data[MAX_PCE_SIZE];
81  uint8_t *extradata;
82 
83  if (!hdr.chan_config) {
84  init_get_bits(&gb, pkt->data, pkt->size * 8);
85  if (get_bits(&gb, 3) != 5) {
87  "PCE-based channel configuration "
88  "without PCE as first syntax "
89  "element");
91  goto fail;
92  }
93  init_put_bits(&pb, pce_data, MAX_PCE_SIZE);
94  pce_size = ff_copy_pce_data(&pb, &gb) / 8;
95  flush_put_bits(&pb);
96  pkt->size -= get_bits_count(&gb)/8;
97  pkt->data += get_bits_count(&gb)/8;
98  }
99 
101  2 + pce_size);
102  if (!extradata) {
103  ret = AVERROR(ENOMEM);
104  goto fail;
105  }
106 
107  init_put_bits(&pb, extradata, 2 + pce_size);
108  put_bits(&pb, 5, hdr.object_type);
109  put_bits(&pb, 4, hdr.sampling_index);
110  put_bits(&pb, 4, hdr.chan_config);
111  put_bits(&pb, 1, 0); //frame length - 1024 samples
112  put_bits(&pb, 1, 0); //does not depend on core coder
113  put_bits(&pb, 1, 0); //is not extension
114  flush_put_bits(&pb);
115  if (pce_size) {
116  memcpy(extradata + 2, pce_data, pce_size);
117  }
118 
119  ctx->first_frame_done = 1;
120  }
121 
122  return 0;
123 
124 packet_too_small:
125  av_log(bsfc, AV_LOG_ERROR, "Input packet too small\n");
126  ret = AVERROR_INVALIDDATA;
127 fail:
128  av_packet_unref(pkt);
129  return ret;
130 }
131 
133 {
134  /* Validate the extradata if the stream is already MPEG-4 AudioSpecificConfig */
135  if (ctx->par_in->extradata) {
136  MPEG4AudioConfig mp4ac;
137  int ret = avpriv_mpeg4audio_get_config(&mp4ac, ctx->par_in->extradata,
138  ctx->par_in->extradata_size * 8, 1);
139  if (ret < 0) {
140  av_log(ctx, AV_LOG_ERROR, "Error parsing AudioSpecificConfig extradata!\n");
141  return ret;
142  }
143  }
144 
145  return 0;
146 }
147 
148 static const enum AVCodecID codec_ids[] = {
150 };
151 
153  .name = "aac_adtstoasc",
154  .priv_data_size = sizeof(AACBSFContext),
157  .codec_ids = codec_ids,
158 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
uint8_t object_type
Definition: adts_header.h:33
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:208
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:269
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
The bitstream filter state.
Definition: avcodec.h:5688
int size
Definition: avcodec.h:1432
static int aac_adtstoasc_init(AVBSFContext *ctx)
static AVPacket pkt
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:87
void * priv_data
Opaque filter-specific private data.
Definition: avcodec.h:5709
static void filter(int16_t *output, ptrdiff_t out_stride, int16_t *low, ptrdiff_t low_stride, int16_t *high, ptrdiff_t high_stride, int len, int clip)
Definition: cfhd.c:153
uint8_t
const AVBitStreamFilter ff_aac_adtstoasc_bsf
const char * name
Definition: avcodec.h:5738
uint8_t * data
Definition: avcodec.h:1431
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:200
bitstream reader API header.
#define av_log(a,...)
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:215
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
uint8_t sampling_index
Definition: adts_header.h:34
#define fail()
Definition: checkasm.h:117
#define AV_AAC_ADTS_HEADER_SIZE
Definition: adts_parser.h:25
uint8_t chan_config
Definition: adts_header.h:35
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3903
static int aac_adtstoasc_filter(AVBSFContext *bsfc, AVPacket *pkt)
This filter creates an MPEG-4 AudioSpecificConfig from an MPEG-2/4 ADTS header and removes the ADTS h...
uint8_t num_aac_frames
Definition: adts_header.h:36
AVFormatContext * ctx
Definition: movenc.c:48
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
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
The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format that the extradata buffer was...
Definition: avcodec.h:1159
Libavcodec external API header.
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:592
static int ff_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
Definition: mpeg4audio.h:131
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:433
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
common internal api header.
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:101
static enum AVCodecID codec_ids[]
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:48
#define MAX_PCE_SIZE
Maximum size of a PCE including the 3-bit ID_PCE.
Definition: mpeg4audio.h:119
int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, int bit_size, int sync_extension)
Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration. ...
Definition: mpeg4audio.c:155
uint8_t crc_absent
Definition: adts_header.h:32
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3899
uint8_t * av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int size)
Allocate new information of a packet.
Definition: avpacket.c:329
This structure stores compressed data.
Definition: avcodec.h:1408
AVCodecParameters * par_in
Parameters of the input stream.
Definition: avcodec.h:5716
int ff_bsf_get_packet_ref(AVBSFContext *ctx, AVPacket *pkt)
Called by bitstream filters to get packet for filtering.
Definition: bsf.c:228
bitstream writer API