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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 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 "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 {
34  av_assert0(sizeof(*g) == 16); //compiler will optimize this out
35  if (avio_read(s, *g, sizeof(*g)) < (int)sizeof(*g)) {
36  memset(*g, 0, sizeof(*g));
37  return AVERROR_INVALIDDATA;
38  }
39  return 0;
40 }
41 
43 {
44  int i;
45  for (i = 0; guids[i].id != AV_CODEC_ID_NONE; i++)
46  if (!ff_guidcmp(guids[i].guid, guid))
47  return guids[i].id;
48  return AV_CODEC_ID_NONE;
49 }
50 
51 /* We could be given one of the three possible structures here:
52  * WAVEFORMAT, PCMWAVEFORMAT or WAVEFORMATEX. Each structure
53  * is an expansion of the previous one with the fields added
54  * at the bottom. PCMWAVEFORMAT adds 'WORD wBitsPerSample' and
55  * WAVEFORMATEX adds 'WORD cbSize' and basically makes itself
56  * an openended structure.
57  */
58 
60 {
61  ff_asf_guid subformat;
62  int bps = avio_rl16(pb);
63  if (bps)
65 
66  c->channel_layout = avio_rl32(pb); /* dwChannelMask */
67 
68  ff_get_guid(pb, &subformat);
69  if (!memcmp(subformat + 4,
70  (const uint8_t[]){ FF_MEDIASUBTYPE_BASE_GUID }, 12)) {
71  c->codec_tag = AV_RL32(subformat);
74  } else {
76  if (!c->codec_id)
78  "unknown subformat:"FF_PRI_GUID"\n",
79  FF_ARG_GUID(subformat));
80  }
81 }
82 
83 /* "big_endian" values are needed for RIFX file format */
85  AVCodecContext *codec, int size, int big_endian)
86 {
87  int id;
88 
89  if (size < 14)
90  avpriv_request_sample(codec, "wav header size < 14");
91 
93  if (!big_endian) {
94  id = avio_rl16(pb);
95  codec->channels = avio_rl16(pb);
96  codec->sample_rate = avio_rl32(pb);
97  codec->bit_rate = avio_rl32(pb) * 8;
98  codec->block_align = avio_rl16(pb);
99  } else {
100  id = avio_rb16(pb);
101  codec->channels = avio_rb16(pb);
102  codec->sample_rate = avio_rb32(pb);
103  codec->bit_rate = avio_rb32(pb) * 8;
104  codec->block_align = avio_rb16(pb);
105  }
106  if (codec->bit_rate < 0) {
108  "Invalid bit rate: %d\n", codec->bit_rate);
110  return AVERROR_INVALIDDATA;
111  else
112  codec->bit_rate = 0;
113  }
114  if (size == 14) { /* We're dealing with plain vanilla WAVEFORMAT */
115  codec->bits_per_coded_sample = 8;
116  } else {
117  if (!big_endian) {
118  codec->bits_per_coded_sample = avio_rl16(pb);
119  } else {
120  codec->bits_per_coded_sample = avio_rb16(pb);
121  }
122  }
123  if (id == 0xFFFE) {
124  codec->codec_tag = 0;
125  } else {
126  codec->codec_tag = id;
127  codec->codec_id = ff_wav_codec_get_id(id,
128  codec->bits_per_coded_sample);
129  }
130  if (size >= 18) { /* We're obviously dealing with WAVEFORMATEX */
131  int cbSize = avio_rl16(pb); /* cbSize */
132  if (big_endian) {
133  avpriv_report_missing_feature(codec, "WAVEFORMATEX support for RIFX files\n");
134  return AVERROR_PATCHWELCOME;
135  }
136  size -= 18;
137  cbSize = FFMIN(size, cbSize);
138  if (cbSize >= 22 && id == 0xfffe) { /* WAVEFORMATEXTENSIBLE */
139  parse_waveformatex(pb, codec);
140  cbSize -= 22;
141  size -= 22;
142  }
143  if (cbSize > 0) {
144  av_freep(&codec->extradata);
145  if (ff_get_extradata(codec, pb, cbSize) < 0)
146  return AVERROR(ENOMEM);
147  size -= cbSize;
148  }
149 
150  /* It is possible for the chunk to contain garbage at the end */
151  if (size > 0)
152  avio_skip(pb, size);
153  }
154  if (codec->sample_rate <= 0) {
155  av_log(s, AV_LOG_ERROR,
156  "Invalid sample rate: %d\n", codec->sample_rate);
157  return AVERROR_INVALIDDATA;
158  }
159  if (codec->codec_id == AV_CODEC_ID_AAC_LATM) {
160  /* Channels and sample_rate values are those prior to applying SBR
161  * and/or PS. */
162  codec->channels = 0;
163  codec->sample_rate = 0;
164  }
165  /* override bits_per_coded_sample for G.726 */
166  if (codec->codec_id == AV_CODEC_ID_ADPCM_G726 && codec->sample_rate)
167  codec->bits_per_coded_sample = codec->bit_rate / codec->sample_rate;
168 
169  return 0;
170 }
171 
172 enum AVCodecID ff_wav_codec_get_id(unsigned int tag, int bps)
173 {
174  enum AVCodecID id;
176  if (id <= 0)
177  return id;
178 
179  if (id == AV_CODEC_ID_PCM_S16LE)
180  id = ff_get_pcm_codec_id(bps, 0, 0, ~1);
181  else if (id == AV_CODEC_ID_PCM_F32LE)
182  id = ff_get_pcm_codec_id(bps, 1, 0, 0);
183 
184  if (id == AV_CODEC_ID_ADPCM_IMA_WAV && bps == 8)
186  return id;
187 }
188 
189 int ff_get_bmp_header(AVIOContext *pb, AVStream *st, unsigned *esize)
190 {
191  int tag1;
192  if(esize) *esize = avio_rl32(pb);
193  else avio_rl32(pb);
194  st->codec->width = avio_rl32(pb);
195  st->codec->height = (int32_t)avio_rl32(pb);
196  avio_rl16(pb); /* planes */
197  st->codec->bits_per_coded_sample = avio_rl16(pb); /* depth */
198  tag1 = avio_rl32(pb);
199  avio_rl32(pb); /* ImageSize */
200  avio_rl32(pb); /* XPelsPerMeter */
201  avio_rl32(pb); /* YPelsPerMeter */
202  avio_rl32(pb); /* ClrUsed */
203  avio_rl32(pb); /* ClrImportant */
204  return tag1;
205 }
206 
208 {
209  int64_t start, end, cur;
210  AVIOContext *pb = s->pb;
211 
212  start = avio_tell(pb);
213  end = start + size;
214 
215  while ((cur = avio_tell(pb)) >= 0 &&
216  cur <= end - 8 /* = tag + size */) {
217  uint32_t chunk_code;
218  int64_t chunk_size;
219  char key[5] = { 0 };
220  char *value;
221 
222  chunk_code = avio_rl32(pb);
223  chunk_size = avio_rl32(pb);
224  if (avio_feof(pb)) {
225  if (chunk_code || chunk_size) {
226  av_log(s, AV_LOG_WARNING, "INFO subchunk truncated\n");
227  return AVERROR_INVALIDDATA;
228  }
229  return AVERROR_EOF;
230  }
231  if (chunk_size > end ||
232  end - chunk_size < cur ||
233  chunk_size == UINT_MAX) {
234  avio_seek(pb, -9, SEEK_CUR);
235  chunk_code = avio_rl32(pb);
236  chunk_size = avio_rl32(pb);
237  if (chunk_size > end || end - chunk_size < cur || chunk_size == UINT_MAX) {
238  av_log(s, AV_LOG_WARNING, "too big INFO subchunk\n");
239  return AVERROR_INVALIDDATA;
240  }
241  }
242 
243  chunk_size += (chunk_size & 1);
244 
245  if (!chunk_code) {
246  if (chunk_size)
247  avio_skip(pb, chunk_size);
248  else if (pb->eof_reached) {
249  av_log(s, AV_LOG_WARNING, "truncated file\n");
250  return AVERROR_EOF;
251  }
252  continue;
253  }
254 
255  value = av_mallocz(chunk_size + 1);
256  if (!value) {
257  av_log(s, AV_LOG_ERROR,
258  "out of memory, unable to read INFO tag\n");
259  return AVERROR(ENOMEM);
260  }
261 
262  AV_WL32(key, chunk_code);
263 
264  if (avio_read(pb, value, chunk_size) != chunk_size) {
266  "premature end of file while reading INFO tag\n");
267  }
268 
269  av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
270  }
271 
272  return 0;
273 }
const char * s
Definition: avisynth_c.h:669
Bytestream IO Context.
Definition: avio.h:68
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int ff_get_bmp_header(AVIOContext *pb, AVStream *st, unsigned *esize)
Read BITMAPINFOHEADER structure and set AVStream codec width, height and bits_per_encoded_sample fiel...
Definition: riffdec.c:189
enum AVCodecID id
Definition: mxfenc.c:95
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:2705
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:181
#define FF_ARG_GUID(g)
Definition: riff.h:97
const char * g
Definition: vf_curves.c:108
int ff_get_extradata(AVCodecContext *avctx, AVIOContext *pb, int size)
Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: utils.c:2880
enum AVCodecID id
Definition: riff.h:87
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:203
enum AVCodecID ff_wav_codec_get_id(unsigned int tag, int bps)
Definition: riffdec.c:172
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:276
int ff_get_wav_header(AVFormatContext *s, AVIOContext *pb, AVCodecContext *codec, int size, int big_endian)
Definition: riffdec.c:84
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:666
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:2020
const AVCodecGuid ff_codec_wav_guids[]
Definition: riff.c:471
Format I/O context.
Definition: avformat.h:1226
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
Public dictionary API.
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
uint8_t
#define FF_MEDIASUBTYPE_BASE_GUID
Definition: riff.h:103
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:681
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:67
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1353
static void parse_waveformatex(AVIOContext *pb, AVCodecContext *c)
Definition: riffdec.c:59
uint32_t tag
Definition: movenc.c:1332
#define AVERROR_EOF
End of file.
Definition: error.h:55
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:273
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2718
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:537
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:102
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:175
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1435
error code definitions
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:2621
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:650
#define AVERROR(e)
Definition: error.h:43
enum AVCodecID ff_codec_guid_get_id(const AVCodecGuid *guids, ff_asf_guid guid)
Definition: riffdec.c:42
const AVCodecTag ff_codec_wav_tags[]
Definition: riff.c:369
Libavcodec external API header.
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2044
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:826
int bit_rate
the average bitrate
Definition: avcodec.h:1303
#define FFMIN(a, b)
Definition: common.h:81
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:78
int width
picture width / height.
Definition: avcodec.h:1412
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:109
internal header for RIFF based (de)muxers do NOT include this in end user applications ...
int32_t
#define AV_RL32
Definition: intreadwrite.h:146
uint8_t ff_asf_guid[16]
Definition: riff.h:84
Stream structure.
Definition: avformat.h:807
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
enum AVMediaType codec_type
Definition: avcodec.h:1247
enum AVCodecID codec_id
Definition: avcodec.h:1256
int sample_rate
samples per second
Definition: avcodec.h:1983
AVIOContext * pb
I/O context.
Definition: avformat.h:1268
main external API structure.
Definition: avcodec.h:1239
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1271
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:69
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:2717
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:634
Main libavformat public API header.
static double c[64]
#define FF_PRI_GUID
Definition: riff.h:93
int error_recognition
Error recognition; higher values will detect more errors but may misdetect some more or less valid pa...
Definition: avformat.h:1462
unsigned bps
Definition: movenc.c:1333
int eof_reached
true if eof reached
Definition: avio.h:96
int channels
number of audio channels
Definition: avcodec.h:1984
int ff_get_guid(AVIOContext *s, ff_asf_guid *g)
Definition: riffdec.c:32
#define av_freep(p)
int ff_read_riff_info(AVFormatContext *s, int64_t size)
Definition: riffdec.c:207
void INT64 start
Definition: avisynth_c.h:595
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:300
static av_always_inline int ff_guidcmp(const void *g1, const void *g2)
Definition: riff.h:106
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:250
#define AV_WL32(p, v)
Definition: intreadwrite.h:426