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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  { 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  av_assert0(sizeof(*g) == 16); //compiler will optimize this out
43  if (avio_read(s, *g, sizeof(*g)) < (int)sizeof(*g))
44  memset(*g, 0, sizeof(*g));
45 }
46 
48 {
49  int i;
50  for (i = 0; guids[i].id != AV_CODEC_ID_NONE; i++)
51  if (!ff_guidcmp(guids[i].guid, guid))
52  return guids[i].id;
53  return AV_CODEC_ID_NONE;
54 }
55 
56 /* We could be given one of the three possible structures here:
57  * WAVEFORMAT, PCMWAVEFORMAT or WAVEFORMATEX. Each structure
58  * is an expansion of the previous one with the fields added
59  * at the bottom. PCMWAVEFORMAT adds 'WORD wBitsPerSample' and
60  * WAVEFORMATEX adds 'WORD cbSize' and basically makes itself
61  * an openended structure.
62  */
63 
65 {
66  ff_asf_guid subformat;
67  int bps = avio_rl16(pb);
68  if (bps)
70 
71  c->channel_layout = avio_rl32(pb); /* dwChannelMask */
72 
73  ff_get_guid(pb, &subformat);
74  if (!memcmp(subformat + 4,
75  (const uint8_t[]){ FF_MEDIASUBTYPE_BASE_GUID }, 12)) {
76  c->codec_tag = AV_RL32(subformat);
79  } else {
80  c->codec_id = ff_codec_guid_get_id(ff_codec_wav_guids, subformat);
81  if (!c->codec_id)
83  "unknown subformat:"FF_PRI_GUID"\n",
84  FF_ARG_GUID(subformat));
85  }
86 }
87 
89 {
90  int id;
91 
92  id = avio_rl16(pb);
94  codec->channels = avio_rl16(pb);
95  codec->sample_rate = avio_rl32(pb);
96  codec->bit_rate = avio_rl32(pb) * 8;
97  codec->block_align = avio_rl16(pb);
98  if (size == 14) { /* We're dealing with plain vanilla WAVEFORMAT */
99  codec->bits_per_coded_sample = 8;
100  } else
101  codec->bits_per_coded_sample = avio_rl16(pb);
102  if (id == 0xFFFE) {
103  codec->codec_tag = 0;
104  } else {
105  codec->codec_tag = id;
106  codec->codec_id = ff_wav_codec_get_id(id,
107  codec->bits_per_coded_sample);
108  }
109  if (size >= 18) { /* We're obviously dealing with WAVEFORMATEX */
110  int cbSize = avio_rl16(pb); /* cbSize */
111  size -= 18;
112  cbSize = FFMIN(size, cbSize);
113  if (cbSize >= 22 && id == 0xfffe) { /* WAVEFORMATEXTENSIBLE */
114  parse_waveformatex(pb, codec);
115  cbSize -= 22;
116  size -= 22;
117  }
118  if (cbSize > 0) {
119  av_free(codec->extradata);
120  if (ff_alloc_extradata(codec, cbSize))
121  return AVERROR(ENOMEM);
122  avio_read(pb, codec->extradata, codec->extradata_size);
123  size -= cbSize;
124  }
125 
126  /* It is possible for the chunk to contain garbage at the end */
127  if (size > 0)
128  avio_skip(pb, size);
129  }
130  if (codec->sample_rate <= 0) {
131  av_log(NULL, AV_LOG_ERROR,
132  "Invalid sample rate: %d\n", codec->sample_rate);
133  return AVERROR_INVALIDDATA;
134  }
135  if (codec->codec_id == AV_CODEC_ID_AAC_LATM) {
136  /* Channels and sample_rate values are those prior to applying SBR
137  * and/or PS. */
138  codec->channels = 0;
139  codec->sample_rate = 0;
140  }
141  /* override bits_per_coded_sample for G.726 */
142  if (codec->codec_id == AV_CODEC_ID_ADPCM_G726 && codec->sample_rate)
143  codec->bits_per_coded_sample = codec->bit_rate / codec->sample_rate;
144 
145  return 0;
146 }
147 
148 enum AVCodecID ff_wav_codec_get_id(unsigned int tag, int bps)
149 {
150  enum AVCodecID id;
152  if (id <= 0)
153  return id;
154 
155  if (id == AV_CODEC_ID_PCM_S16LE)
156  id = ff_get_pcm_codec_id(bps, 0, 0, ~1);
157  else if (id == AV_CODEC_ID_PCM_F32LE)
158  id = ff_get_pcm_codec_id(bps, 1, 0, 0);
159 
160  if (id == AV_CODEC_ID_ADPCM_IMA_WAV && bps == 8)
162  return id;
163 }
164 
165 int ff_get_bmp_header(AVIOContext *pb, AVStream *st, unsigned *esize)
166 {
167  int tag1;
168  if(esize) *esize = avio_rl32(pb);
169  else avio_rl32(pb);
170  st->codec->width = avio_rl32(pb);
171  st->codec->height = (int32_t)avio_rl32(pb);
172  avio_rl16(pb); /* planes */
173  st->codec->bits_per_coded_sample = avio_rl16(pb); /* depth */
174  tag1 = avio_rl32(pb);
175  avio_rl32(pb); /* ImageSize */
176  avio_rl32(pb); /* XPelsPerMeter */
177  avio_rl32(pb); /* YPelsPerMeter */
178  avio_rl32(pb); /* ClrUsed */
179  avio_rl32(pb); /* ClrImportant */
180  return tag1;
181 }
182 
184 {
185  int64_t start, end, cur;
186  AVIOContext *pb = s->pb;
187 
188  start = avio_tell(pb);
189  end = start + size;
190 
191  while ((cur = avio_tell(pb)) >= 0 &&
192  cur <= end - 8 /* = tag + size */) {
193  uint32_t chunk_code;
194  int64_t chunk_size;
195  char key[5] = { 0 };
196  char *value;
197 
198  chunk_code = avio_rl32(pb);
199  chunk_size = avio_rl32(pb);
200  if (url_feof(pb)) {
201  if (chunk_code || chunk_size) {
202  av_log(s, AV_LOG_WARNING, "INFO subchunk truncated\n");
203  return AVERROR_INVALIDDATA;
204  }
205  return AVERROR_EOF;
206  }
207  if (chunk_size > end ||
208  end - chunk_size < cur ||
209  chunk_size == UINT_MAX) {
210  avio_seek(pb, -9, SEEK_CUR);
211  chunk_code = avio_rl32(pb);
212  chunk_size = avio_rl32(pb);
213  if (chunk_size > end || end - chunk_size < cur || chunk_size == UINT_MAX) {
214  av_log(s, AV_LOG_WARNING, "too big INFO subchunk\n");
215  return AVERROR_INVALIDDATA;
216  }
217  }
218 
219  chunk_size += (chunk_size & 1);
220 
221  if (!chunk_code) {
222  if (chunk_size)
223  avio_skip(pb, chunk_size);
224  else if (pb->eof_reached) {
225  av_log(s, AV_LOG_WARNING, "truncated file\n");
226  return AVERROR_EOF;
227  }
228  continue;
229  }
230 
231  value = av_mallocz(chunk_size + 1);
232  if (!value) {
233  av_log(s, AV_LOG_ERROR,
234  "out of memory, unable to read INFO tag\n");
235  return AVERROR(ENOMEM);
236  }
237 
238  AV_WL32(key, chunk_code);
239 
240  if (avio_read(pb, value, chunk_size) != chunk_size) {
242  "premature end of file while reading INFO tag\n");
243  }
244 
245  av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
246  }
247 
248  return 0;
249 }