Libav
wvdec.c
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1 /*
2  * WavPack demuxer
3  * Copyright (c) 2006,2011 Konstantin Shishkov
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 
23 #include "libavutil/intreadwrite.h"
24 #include "libavutil/dict.h"
25 #include "avformat.h"
26 #include "internal.h"
27 #include "apetag.h"
28 #include "id3v1.h"
29 #include "wv.h"
30 
31 enum WV_FLAGS {
32  WV_MONO = 0x0004,
33  WV_HYBRID = 0x0008,
34  WV_JOINT = 0x0010,
35  WV_CROSSD = 0x0020,
36  WV_HSHAPE = 0x0040,
37  WV_FLOAT = 0x0080,
38  WV_INT32 = 0x0100,
39  WV_HBR = 0x0200,
40  WV_HBAL = 0x0400,
41  WV_MCINIT = 0x0800,
42  WV_MCEND = 0x1000,
43 };
44 
45 static const int wv_rates[16] = {
46  6000, 8000, 9600, 11025, 12000, 16000, 22050, 24000,
47  32000, 44100, 48000, 64000, 88200, 96000, 192000, -1
48 };
49 
50 typedef struct {
51  uint8_t block_header[WV_HEADER_SIZE];
53  int rate, chan, bpp;
54  uint32_t chmask;
57  int64_t pos;
58 
59  int64_t apetag_start;
60 } WVContext;
61 
62 static int wv_probe(AVProbeData *p)
63 {
64  /* check file header */
65  if (p->buf_size <= 32)
66  return 0;
67  if (p->buf[0] == 'w' && p->buf[1] == 'v' &&
68  p->buf[2] == 'p' && p->buf[3] == 'k')
69  return AVPROBE_SCORE_MAX;
70  else
71  return 0;
72 }
73 
75 {
76  WVContext *wc = ctx->priv_data;
77  int ret;
78  int rate, bpp, chan;
79  uint32_t chmask, flags;
80 
81  wc->pos = avio_tell(pb);
82 
83  /* don't return bogus packets with the ape tag data */
84  if (wc->apetag_start && wc->pos >= wc->apetag_start)
85  return AVERROR_EOF;
86 
87  ret = avio_read(pb, wc->block_header, WV_HEADER_SIZE);
88  if (ret != WV_HEADER_SIZE)
89  return (ret < 0) ? ret : AVERROR_EOF;
90 
91  ret = ff_wv_parse_header(&wc->header, wc->block_header);
92  if (ret < 0) {
93  av_log(ctx, AV_LOG_ERROR, "Invalid block header.\n");
94  return ret;
95  }
96 
97  if (wc->header.version < 0x402 || wc->header.version > 0x410) {
98  av_log(ctx, AV_LOG_ERROR, "Unsupported version %03X\n", wc->header.version);
99  return AVERROR_PATCHWELCOME;
100  }
101 
102  /* Blocks with zero samples don't contain actual audio information
103  * and should be ignored */
104  if (!wc->header.samples)
105  return 0;
106  // parse flags
107  flags = wc->header.flags;
108  bpp = ((flags & 3) + 1) << 3;
109  chan = 1 + !(flags & WV_MONO);
110  chmask = flags & WV_MONO ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;
111  rate = wv_rates[(flags >> 23) & 0xF];
112  wc->multichannel = !(wc->header.initial && wc->header.final);
113  if (wc->multichannel) {
114  chan = wc->chan;
115  chmask = wc->chmask;
116  }
117  if ((rate == -1 || !chan) && !wc->block_parsed) {
118  int64_t block_end = avio_tell(pb) + wc->header.blocksize;
119  if (!pb->seekable) {
120  av_log(ctx, AV_LOG_ERROR,
121  "Cannot determine additional parameters\n");
122  return AVERROR_INVALIDDATA;
123  }
124  while (avio_tell(pb) < block_end) {
125  int id, size;
126  id = avio_r8(pb);
127  size = (id & 0x80) ? avio_rl24(pb) : avio_r8(pb);
128  size <<= 1;
129  if (id & 0x40)
130  size--;
131  switch (id & 0x3F) {
132  case 0xD:
133  if (size <= 1) {
134  av_log(ctx, AV_LOG_ERROR,
135  "Insufficient channel information\n");
136  return AVERROR_INVALIDDATA;
137  }
138  chan = avio_r8(pb);
139  switch (size - 2) {
140  case 0:
141  chmask = avio_r8(pb);
142  break;
143  case 1:
144  chmask = avio_rl16(pb);
145  break;
146  case 2:
147  chmask = avio_rl24(pb);
148  break;
149  case 3:
150  chmask = avio_rl32(pb);
151  break;
152  case 5:
153  avio_skip(pb, 1);
154  chan |= (avio_r8(pb) & 0xF) << 8;
155  chmask = avio_rl24(pb);
156  break;
157  default:
158  av_log(ctx, AV_LOG_ERROR,
159  "Invalid channel info size %d\n", size);
160  return AVERROR_INVALIDDATA;
161  }
162  break;
163  case 0x27:
164  rate = avio_rl24(pb);
165  break;
166  default:
167  avio_skip(pb, size);
168  }
169  if (id & 0x40)
170  avio_skip(pb, 1);
171  }
172  if (rate == -1) {
173  av_log(ctx, AV_LOG_ERROR,
174  "Cannot determine custom sampling rate\n");
175  return AVERROR_INVALIDDATA;
176  }
177  avio_seek(pb, block_end - wc->header.blocksize, SEEK_SET);
178  }
179  if (!wc->bpp)
180  wc->bpp = bpp;
181  if (!wc->chan)
182  wc->chan = chan;
183  if (!wc->chmask)
184  wc->chmask = chmask;
185  if (!wc->rate)
186  wc->rate = rate;
187 
188  if (flags && bpp != wc->bpp) {
189  av_log(ctx, AV_LOG_ERROR,
190  "Bits per sample differ, this block: %i, header block: %i\n",
191  bpp, wc->bpp);
192  return AVERROR_INVALIDDATA;
193  }
194  if (flags && !wc->multichannel && chan != wc->chan) {
195  av_log(ctx, AV_LOG_ERROR,
196  "Channels differ, this block: %i, header block: %i\n",
197  chan, wc->chan);
198  return AVERROR_INVALIDDATA;
199  }
200  if (flags && rate != -1 && rate != wc->rate) {
201  av_log(ctx, AV_LOG_ERROR,
202  "Sampling rate differ, this block: %i, header block: %i\n",
203  rate, wc->rate);
204  return AVERROR_INVALIDDATA;
205  }
206  return 0;
207 }
208 
210 {
211  AVIOContext *pb = s->pb;
212  WVContext *wc = s->priv_data;
213  AVStream *st;
214  int ret;
215 
216  wc->block_parsed = 0;
217  for (;;) {
218  if ((ret = wv_read_block_header(s, pb)) < 0)
219  return ret;
220  if (!wc->header.samples)
221  avio_skip(pb, wc->header.blocksize);
222  else
223  break;
224  }
225 
226  /* now we are ready: build format streams */
227  st = avformat_new_stream(s, NULL);
228  if (!st)
229  return AVERROR(ENOMEM);
232  st->codec->channels = wc->chan;
233  st->codec->channel_layout = wc->chmask;
234  st->codec->sample_rate = wc->rate;
235  st->codec->bits_per_coded_sample = wc->bpp;
236  avpriv_set_pts_info(st, 64, 1, wc->rate);
237  st->start_time = 0;
238  st->duration = wc->header.total_samples;
239 
240  if (s->pb->seekable) {
241  int64_t cur = avio_tell(s->pb);
244  ff_id3v1_read(s);
245  avio_seek(s->pb, cur, SEEK_SET);
246  }
247 
248  return 0;
249 }
250 
252 {
253  WVContext *wc = s->priv_data;
254  int ret;
255  int off;
256  int64_t pos;
257  uint32_t block_samples;
258 
259  if (s->pb->eof_reached)
260  return AVERROR_EOF;
261  if (wc->block_parsed) {
262  if ((ret = wv_read_block_header(s, s->pb)) < 0)
263  return ret;
264  }
265 
266  pos = wc->pos;
267  if (av_new_packet(pkt, wc->header.blocksize + WV_HEADER_SIZE) < 0)
268  return AVERROR(ENOMEM);
269  memcpy(pkt->data, wc->block_header, WV_HEADER_SIZE);
270  ret = avio_read(s->pb, pkt->data + WV_HEADER_SIZE, wc->header.blocksize);
271  if (ret != wc->header.blocksize) {
272  av_free_packet(pkt);
273  return AVERROR(EIO);
274  }
275  while (!(wc->header.flags & WV_FLAG_FINAL_BLOCK)) {
276  if ((ret = wv_read_block_header(s, s->pb)) < 0) {
277  av_free_packet(pkt);
278  return ret;
279  }
280 
281  off = pkt->size;
282  if ((ret = av_grow_packet(pkt, WV_HEADER_SIZE + wc->header.blocksize)) < 0) {
283  av_free_packet(pkt);
284  return ret;
285  }
286  memcpy(pkt->data + off, wc->block_header, WV_HEADER_SIZE);
287 
288  ret = avio_read(s->pb, pkt->data + off + WV_HEADER_SIZE, wc->header.blocksize);
289  if (ret != wc->header.blocksize) {
290  av_free_packet(pkt);
291  return (ret < 0) ? ret : AVERROR_EOF;
292  }
293  }
294  pkt->stream_index = 0;
295  wc->block_parsed = 1;
296  pkt->pts = wc->header.block_idx;
297  block_samples = wc->header.samples;
298  if (block_samples > INT32_MAX)
300  "Too many samples in block: %"PRIu32"\n", block_samples);
301  else
302  pkt->duration = block_samples;
303 
304  av_add_index_entry(s->streams[0], pos, pkt->pts, 0, 0, AVINDEX_KEYFRAME);
305  return 0;
306 }
307 
308 static int wv_read_seek(AVFormatContext *s, int stream_index,
309  int64_t timestamp, int flags)
310 {
311  AVStream *st = s->streams[stream_index];
312  WVContext *wc = s->priv_data;
313  AVPacket pkt1, *pkt = &pkt1;
314  int ret;
315  int index = av_index_search_timestamp(st, timestamp, flags);
316  int64_t pos, pts;
317 
318  /* if found, seek there */
319  if (index >= 0 &&
320  timestamp <= st->index_entries[st->nb_index_entries - 1].timestamp) {
321  wc->block_parsed = 1;
322  avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET);
323  return 0;
324  }
325  /* if timestamp is out of bounds, return error */
326  if (timestamp < 0 || timestamp >= s->duration)
327  return AVERROR(EINVAL);
328 
329  pos = avio_tell(s->pb);
330  do {
331  ret = av_read_frame(s, pkt);
332  if (ret < 0) {
333  avio_seek(s->pb, pos, SEEK_SET);
334  return ret;
335  }
336  pts = pkt->pts;
337  av_free_packet(pkt);
338  } while(pts < timestamp);
339  return 0;
340 }
341 
343  .name = "wv",
344  .long_name = NULL_IF_CONFIG_SMALL("WavPack"),
345  .priv_data_size = sizeof(WVContext),
346  .read_probe = wv_probe,
350 };