Libav
riffdec.c
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1 /*
2  * RIFF demuxing functions and data
3  * Copyright (c) 2000 Fabrice Bellard
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/dict.h"
23 #include "libavutil/error.h"
24 #include "libavutil/log.h"
25 #include "libavutil/mathematics.h"
26 #include "libavcodec/avcodec.h"
27 #include "libavcodec/bytestream.h"
28 #include "avformat.h"
29 #include "avio_internal.h"
30 #include "riff.h"
31 
33  { AV_CODEC_ID_AC3, { 0x2C, 0x80, 0x6D, 0xE0, 0x46, 0xDB, 0xCF, 0x11, 0xB4, 0xD1, 0x00, 0x80, 0x5F, 0x6C, 0xBB, 0xEA } },
34  { AV_CODEC_ID_ATRAC3P, { 0xBF, 0xAA, 0x23, 0xE9, 0x58, 0xCB, 0x71, 0x44, 0xA1, 0x19, 0xFF, 0xFA, 0x01, 0xE4, 0xCE, 0x62 } },
35  { AV_CODEC_ID_EAC3, { 0xAF, 0x87, 0xFB, 0xA7, 0x02, 0x2D, 0xFB, 0x42, 0xA4, 0xD4, 0x05, 0xCD, 0x93, 0x84, 0x3B, 0xDD } },
36  { AV_CODEC_ID_MP2, { 0x2B, 0x80, 0x6D, 0xE0, 0x46, 0xDB, 0xCF, 0x11, 0xB4, 0xD1, 0x00, 0x80, 0x5F, 0x6C, 0xBB, 0xEA } },
38 };
39 
41 {
42  int i;
43  for (i = 0; guids[i].id != AV_CODEC_ID_NONE; i++)
44  if (!ff_guidcmp(guids[i].guid, guid))
45  return guids[i].id;
46  return AV_CODEC_ID_NONE;
47 }
48 
49 /* We could be given one of the three possible structures here:
50  * WAVEFORMAT, PCMWAVEFORMAT or WAVEFORMATEX. Each structure
51  * is an expansion of the previous one with the fields added
52  * at the bottom. PCMWAVEFORMAT adds 'WORD wBitsPerSample' and
53  * WAVEFORMATEX adds 'WORD cbSize' and basically makes itself
54  * an openended structure.
55  */
56 
58 {
59  ff_asf_guid subformat;
61  c->channel_layout = avio_rl32(pb); /* dwChannelMask */
62 
63  ff_get_guid(pb, &subformat);
64  if (!memcmp(subformat + 4,
65  (const uint8_t[]){ FF_MEDIASUBTYPE_BASE_GUID }, 12)) {
66  c->codec_tag = AV_RL32(subformat);
69  } else {
70  c->codec_id = ff_codec_guid_get_id(ff_codec_wav_guids, subformat);
71  if (!c->codec_id)
73  "unknown subformat:"FF_PRI_GUID"\n",
74  FF_ARG_GUID(subformat));
75  }
76 }
77 
79 {
80  int id;
81 
82  id = avio_rl16(pb);
84  codec->channels = avio_rl16(pb);
85  codec->sample_rate = avio_rl32(pb);
86  codec->bit_rate = avio_rl32(pb) * 8;
87  codec->block_align = avio_rl16(pb);
88  if (size == 14) { /* We're dealing with plain vanilla WAVEFORMAT */
89  codec->bits_per_coded_sample = 8;
90  } else
91  codec->bits_per_coded_sample = avio_rl16(pb);
92  if (id == 0xFFFE) {
93  codec->codec_tag = 0;
94  } else {
95  codec->codec_tag = id;
96  codec->codec_id = ff_wav_codec_get_id(id,
97  codec->bits_per_coded_sample);
98  }
99  if (size >= 18) { /* We're obviously dealing with WAVEFORMATEX */
100  int cbSize = avio_rl16(pb); /* cbSize */
101  size -= 18;
102  cbSize = FFMIN(size, cbSize);
103  if (cbSize >= 22 && id == 0xfffe) { /* WAVEFORMATEXTENSIBLE */
104  parse_waveformatex(pb, codec);
105  cbSize -= 22;
106  size -= 22;
107  }
108  codec->extradata_size = cbSize;
109  if (cbSize > 0) {
110  av_free(codec->extradata);
111  codec->extradata = av_mallocz(codec->extradata_size +
113  if (!codec->extradata)
114  return AVERROR(ENOMEM);
115  avio_read(pb, codec->extradata, codec->extradata_size);
116  size -= cbSize;
117  }
118 
119  /* It is possible for the chunk to contain garbage at the end */
120  if (size > 0)
121  avio_skip(pb, size);
122  }
123  if (codec->sample_rate <= 0) {
125  "Invalid sample rate: %d\n", codec->sample_rate);
126  return AVERROR_INVALIDDATA;
127  }
128  if (codec->codec_id == AV_CODEC_ID_AAC_LATM) {
129  /* Channels and sample_rate values are those prior to applying SBR
130  * and/or PS. */
131  codec->channels = 0;
132  codec->sample_rate = 0;
133  }
134  /* override bits_per_coded_sample for G.726 */
135  if (codec->codec_id == AV_CODEC_ID_ADPCM_G726)
136  codec->bits_per_coded_sample = codec->bit_rate / codec->sample_rate;
137 
138  return 0;
139 }
140 
141 enum AVCodecID ff_wav_codec_get_id(unsigned int tag, int bps)
142 {
143  enum AVCodecID id;
145  if (id <= 0)
146  return id;
147 
148  if (id == AV_CODEC_ID_PCM_S16LE)
149  id = ff_get_pcm_codec_id(bps, 0, 0, ~1);
150  else if (id == AV_CODEC_ID_PCM_F32LE)
151  id = ff_get_pcm_codec_id(bps, 1, 0, 0);
152 
153  if (id == AV_CODEC_ID_ADPCM_IMA_WAV && bps == 8)
155  return id;
156 }
157 
159 {
160  int tag1;
161  avio_rl32(pb); /* size */
162  st->codec->width = avio_rl32(pb);
163  st->codec->height = (int32_t)avio_rl32(pb);
164  avio_rl16(pb); /* planes */
165  st->codec->bits_per_coded_sample = avio_rl16(pb); /* depth */
166  tag1 = avio_rl32(pb);
167  avio_rl32(pb); /* ImageSize */
168  avio_rl32(pb); /* XPelsPerMeter */
169  avio_rl32(pb); /* YPelsPerMeter */
170  avio_rl32(pb); /* ClrUsed */
171  avio_rl32(pb); /* ClrImportant */
172  return tag1;
173 }
174 
176 {
177  int64_t start, end, cur;
178  AVIOContext *pb = s->pb;
179 
180  start = avio_tell(pb);
181  end = start + size;
182 
183  while ((cur = avio_tell(pb)) >= 0 &&
184  cur <= end - 8 /* = tag + size */) {
185  uint32_t chunk_code;
186  int64_t chunk_size;
187  char key[5] = { 0 };
188  char *value;
189 
190  chunk_code = avio_rl32(pb);
191  chunk_size = avio_rl32(pb);
192 
193  if (chunk_size > end ||
194  end - chunk_size < cur ||
195  chunk_size == UINT_MAX) {
196  av_log(s, AV_LOG_WARNING, "too big INFO subchunk\n");
197  break;
198  }
199 
200  chunk_size += (chunk_size & 1);
201 
202  if (!chunk_code) {
203  if (chunk_size)
204  avio_skip(pb, chunk_size);
205  else if (pb->eof_reached) {
206  av_log(s, AV_LOG_WARNING, "truncated file\n");
207  return AVERROR_EOF;
208  }
209  continue;
210  }
211 
212  value = av_malloc(chunk_size + 1);
213  if (!value) {
214  av_log(s, AV_LOG_ERROR,
215  "out of memory, unable to read INFO tag\n");
216  return AVERROR(ENOMEM);
217  }
218 
219  AV_WL32(key, chunk_code);
220 
221  if (avio_read(pb, value, chunk_size) != chunk_size) {
222  av_free(value);
224  "premature end of file while reading INFO tag\n");
225  break;
226  }
227 
228  value[chunk_size] = 0;
229 
230  av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
231  }
232 
233  return 0;
234 }
Bytestream IO Context.
Definition: avio.h:68
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
int size
enum AVCodecID id
Definition: mxfenc.c:84
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:1943
static av_always_inline int ff_get_guid(AVIOContext *s, ff_asf_guid *g)
Definition: riff.h:94
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:129
#define FF_ARG_GUID(g)
Definition: riff.h:82
enum AVCodecID id
Definition: riff.h:73
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:718
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:564
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
enum AVCodecID ff_wav_codec_get_id(unsigned int tag, int bps)
Definition: riffdec.c:141
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:1828
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1164
Format I/O context.
Definition: avformat.h:922
uint8_t
#define FF_MEDIASUBTYPE_BASE_GUID
Definition: riff.h:86
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:219
static void parse_waveformatex(AVIOContext *pb, AVCodecContext *c)
Definition: riffdec.c:57
uint32_t tag
Definition: movenc.c:844
#define AVERROR_EOF
End of file.
Definition: error.h:51
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2507
#define AV_WL32(p, d)
Definition: intreadwrite.h:255
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:105
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:186
#define AVERROR(e)
Definition: error.h:43
enum AVCodecID ff_codec_guid_get_id(const AVCodecGuid *guids, ff_asf_guid guid)
Definition: riffdec.c:40
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:548
const AVCodecTag ff_codec_wav_tags[]
Definition: riff.c:353
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1852
#define FF_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:531
int bit_rate
the average bitrate
Definition: avcodec.h:1114
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() and chilren.
Definition: dict.h:66
int width
picture width / height.
Definition: avcodec.h:1224
void * av_malloc(size_t size) av_malloc_attrib 1(1)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
internal header for RIFF based (de)muxers do NOT include this in end user applications ...
int32_t
uint8_t ff_asf_guid[16]
Definition: riff.h:70
Stream structure.
Definition: avformat.h:699
NULL
Definition: eval.c:55
int ff_get_bmp_header(AVIOContext *pb, AVStream *st)
Read BITMAPINFOHEADER structure and set AVStream codec width, height and bits_per_encoded_sample fiel...
Definition: riffdec.c:158
enum AVMediaType codec_type
Definition: avcodec.h:1058
enum AVCodecID codec_id
Definition: avcodec.h:1067
int sample_rate
samples per second
Definition: avcodec.h:1791
main external API structure.
Definition: avcodec.h:1050
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1082
AVIOContext * pb
I/O context.
Definition: avformat.h:964
int extradata_size
Definition: avcodec.h:1165
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:68
int ff_get_wav_header(AVIOContext *pb, AVCodecContext *codec, int size)
Definition: riffdec.c:78
enum AVCodecID ff_get_pcm_codec_id(int bps, int flt, int be, int sflags)
Select a PCM codec based on the given parameters.
Definition: utils.c:1955
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1130
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:452
#define FF_PRI_GUID
Definition: riff.h:79
Main libavformat public API header.
unsigned bps
Definition: movenc.c:845
const AVCodecGuid ff_codec_wav_guids[]
Definition: riffdec.c:32
int eof_reached
true if eof reached
Definition: avio.h:96
#define AV_RL32(x)
Definition: intreadwrite.h:248
int channels
number of audio channels
Definition: avcodec.h:1792
int ff_read_riff_info(AVFormatContext *s, int64_t size)
Definition: riffdec.c:175
static av_always_inline int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: avio.h:210
static av_always_inline int ff_guidcmp(const void *g1, const void *g2)
Definition: riff.h:89
#define FFMIN(a, b)
Definition: common.h:57
void * av_mallocz(size_t size) av_malloc_attrib 1(1)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:205