ape.c
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1 /*
2  * Monkey's Audio APE demuxer
3  * Copyright (c) 2007 Benjamin Zores <ben@geexbox.org>
4  * based upon libdemac from Dave Chapman.
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include <stdio.h>
24 
25 #include "libavutil/intreadwrite.h"
26 #include "avformat.h"
27 #include "internal.h"
28 #include "apetag.h"
29 
30 /* The earliest and latest file formats supported by this library */
31 #define APE_MIN_VERSION 3950
32 #define APE_MAX_VERSION 3990
33 
34 #define MAC_FORMAT_FLAG_8_BIT 1 // is 8-bit [OBSOLETE]
35 #define MAC_FORMAT_FLAG_CRC 2 // uses the new CRC32 error detection [OBSOLETE]
36 #define MAC_FORMAT_FLAG_HAS_PEAK_LEVEL 4 // uint32 nPeakLevel after the header [OBSOLETE]
37 #define MAC_FORMAT_FLAG_24_BIT 8 // is 24-bit [OBSOLETE]
38 #define MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS 16 // has the number of seek elements after the peak level
39 #define MAC_FORMAT_FLAG_CREATE_WAV_HEADER 32 // create the wave header on decompression (not stored)
40 
41 #define MAC_SUBFRAME_SIZE 4608
42 
43 #define APE_EXTRADATA_SIZE 6
44 
45 typedef struct {
46  int64_t pos;
47  int nblocks;
48  int size;
49  int skip;
50  int64_t pts;
51 } APEFrame;
52 
53 typedef struct {
54  /* Derived fields */
55  uint32_t junklength;
56  uint32_t firstframe;
57  uint32_t totalsamples;
60 
61  /* Info from Descriptor Block */
62  char magic[4];
63  int16_t fileversion;
64  int16_t padding1;
65  uint32_t descriptorlength;
66  uint32_t headerlength;
67  uint32_t seektablelength;
68  uint32_t wavheaderlength;
69  uint32_t audiodatalength;
71  uint32_t wavtaillength;
72  uint8_t md5[16];
73 
74  /* Info from Header Block */
75  uint16_t compressiontype;
76  uint16_t formatflags;
77  uint32_t blocksperframe;
78  uint32_t finalframeblocks;
79  uint32_t totalframes;
80  uint16_t bps;
81  uint16_t channels;
82  uint32_t samplerate;
83 
84  /* Seektable */
85  uint32_t *seektable;
86 } APEContext;
87 
88 static int ape_probe(AVProbeData * p)
89 {
90  if (p->buf[0] == 'M' && p->buf[1] == 'A' && p->buf[2] == 'C' && p->buf[3] == ' ')
91  return AVPROBE_SCORE_MAX;
92 
93  return 0;
94 }
95 
96 static void ape_dumpinfo(AVFormatContext * s, APEContext * ape_ctx)
97 {
98 #ifdef DEBUG
99  int i;
100 
101  av_log(s, AV_LOG_DEBUG, "Descriptor Block:\n\n");
102  av_log(s, AV_LOG_DEBUG, "magic = \"%c%c%c%c\"\n", ape_ctx->magic[0], ape_ctx->magic[1], ape_ctx->magic[2], ape_ctx->magic[3]);
103  av_log(s, AV_LOG_DEBUG, "fileversion = %"PRId16"\n", ape_ctx->fileversion);
104  av_log(s, AV_LOG_DEBUG, "descriptorlength = %"PRIu32"\n", ape_ctx->descriptorlength);
105  av_log(s, AV_LOG_DEBUG, "headerlength = %"PRIu32"\n", ape_ctx->headerlength);
106  av_log(s, AV_LOG_DEBUG, "seektablelength = %"PRIu32"\n", ape_ctx->seektablelength);
107  av_log(s, AV_LOG_DEBUG, "wavheaderlength = %"PRIu32"\n", ape_ctx->wavheaderlength);
108  av_log(s, AV_LOG_DEBUG, "audiodatalength = %"PRIu32"\n", ape_ctx->audiodatalength);
109  av_log(s, AV_LOG_DEBUG, "audiodatalength_high = %"PRIu32"\n", ape_ctx->audiodatalength_high);
110  av_log(s, AV_LOG_DEBUG, "wavtaillength = %"PRIu32"\n", ape_ctx->wavtaillength);
111  av_log(s, AV_LOG_DEBUG, "md5 = ");
112  for (i = 0; i < 16; i++)
113  av_log(s, AV_LOG_DEBUG, "%02x", ape_ctx->md5[i]);
114  av_log(s, AV_LOG_DEBUG, "\n");
115 
116  av_log(s, AV_LOG_DEBUG, "\nHeader Block:\n\n");
117 
118  av_log(s, AV_LOG_DEBUG, "compressiontype = %"PRIu16"\n", ape_ctx->compressiontype);
119  av_log(s, AV_LOG_DEBUG, "formatflags = %"PRIu16"\n", ape_ctx->formatflags);
120  av_log(s, AV_LOG_DEBUG, "blocksperframe = %"PRIu32"\n", ape_ctx->blocksperframe);
121  av_log(s, AV_LOG_DEBUG, "finalframeblocks = %"PRIu32"\n", ape_ctx->finalframeblocks);
122  av_log(s, AV_LOG_DEBUG, "totalframes = %"PRIu32"\n", ape_ctx->totalframes);
123  av_log(s, AV_LOG_DEBUG, "bps = %"PRIu16"\n", ape_ctx->bps);
124  av_log(s, AV_LOG_DEBUG, "channels = %"PRIu16"\n", ape_ctx->channels);
125  av_log(s, AV_LOG_DEBUG, "samplerate = %"PRIu32"\n", ape_ctx->samplerate);
126 
127  av_log(s, AV_LOG_DEBUG, "\nSeektable\n\n");
128  if ((ape_ctx->seektablelength / sizeof(uint32_t)) != ape_ctx->totalframes) {
129  av_log(s, AV_LOG_DEBUG, "No seektable\n");
130  } else {
131  for (i = 0; i < ape_ctx->seektablelength / sizeof(uint32_t); i++) {
132  if (i < ape_ctx->totalframes - 1) {
133  av_log(s, AV_LOG_DEBUG, "%8d %"PRIu32" (%"PRIu32" bytes)\n",
134  i, ape_ctx->seektable[i],
135  ape_ctx->seektable[i + 1] - ape_ctx->seektable[i]);
136  } else {
137  av_log(s, AV_LOG_DEBUG, "%8d %"PRIu32"\n", i, ape_ctx->seektable[i]);
138  }
139  }
140  }
141 
142  av_log(s, AV_LOG_DEBUG, "\nFrames\n\n");
143  for (i = 0; i < ape_ctx->totalframes; i++)
144  av_log(s, AV_LOG_DEBUG, "%8d %8"PRId64" %8d (%d samples)\n", i,
145  ape_ctx->frames[i].pos, ape_ctx->frames[i].size,
146  ape_ctx->frames[i].nblocks);
147 
148  av_log(s, AV_LOG_DEBUG, "\nCalculated information:\n\n");
149  av_log(s, AV_LOG_DEBUG, "junklength = %"PRIu32"\n", ape_ctx->junklength);
150  av_log(s, AV_LOG_DEBUG, "firstframe = %"PRIu32"\n", ape_ctx->firstframe);
151  av_log(s, AV_LOG_DEBUG, "totalsamples = %"PRIu32"\n", ape_ctx->totalsamples);
152 #endif
153 }
154 
156 {
157  AVIOContext *pb = s->pb;
158  APEContext *ape = s->priv_data;
159  AVStream *st;
160  uint32_t tag;
161  int i;
162  int total_blocks;
163  int64_t pts;
164 
165  /* Skip any leading junk such as id3v2 tags */
166  ape->junklength = avio_tell(pb);
167 
168  tag = avio_rl32(pb);
169  if (tag != MKTAG('M', 'A', 'C', ' '))
170  return -1;
171 
172  ape->fileversion = avio_rl16(pb);
173 
175  av_log(s, AV_LOG_ERROR, "Unsupported file version - %d.%02d\n",
176  ape->fileversion / 1000, (ape->fileversion % 1000) / 10);
177  return -1;
178  }
179 
180  if (ape->fileversion >= 3980) {
181  ape->padding1 = avio_rl16(pb);
182  ape->descriptorlength = avio_rl32(pb);
183  ape->headerlength = avio_rl32(pb);
184  ape->seektablelength = avio_rl32(pb);
185  ape->wavheaderlength = avio_rl32(pb);
186  ape->audiodatalength = avio_rl32(pb);
187  ape->audiodatalength_high = avio_rl32(pb);
188  ape->wavtaillength = avio_rl32(pb);
189  avio_read(pb, ape->md5, 16);
190 
191  /* Skip any unknown bytes at the end of the descriptor.
192  This is for future compatibility */
193  if (ape->descriptorlength > 52)
194  avio_skip(pb, ape->descriptorlength - 52);
195 
196  /* Read header data */
197  ape->compressiontype = avio_rl16(pb);
198  ape->formatflags = avio_rl16(pb);
199  ape->blocksperframe = avio_rl32(pb);
200  ape->finalframeblocks = avio_rl32(pb);
201  ape->totalframes = avio_rl32(pb);
202  ape->bps = avio_rl16(pb);
203  ape->channels = avio_rl16(pb);
204  ape->samplerate = avio_rl32(pb);
205  } else {
206  ape->descriptorlength = 0;
207  ape->headerlength = 32;
208 
209  ape->compressiontype = avio_rl16(pb);
210  ape->formatflags = avio_rl16(pb);
211  ape->channels = avio_rl16(pb);
212  ape->samplerate = avio_rl32(pb);
213  ape->wavheaderlength = avio_rl32(pb);
214  ape->wavtaillength = avio_rl32(pb);
215  ape->totalframes = avio_rl32(pb);
216  ape->finalframeblocks = avio_rl32(pb);
217 
219  avio_skip(pb, 4); /* Skip the peak level */
220  ape->headerlength += 4;
221  }
222 
224  ape->seektablelength = avio_rl32(pb);
225  ape->headerlength += 4;
226  ape->seektablelength *= sizeof(int32_t);
227  } else
228  ape->seektablelength = ape->totalframes * sizeof(int32_t);
229 
231  ape->bps = 8;
232  else if (ape->formatflags & MAC_FORMAT_FLAG_24_BIT)
233  ape->bps = 24;
234  else
235  ape->bps = 16;
236 
237  if (ape->fileversion >= 3950)
238  ape->blocksperframe = 73728 * 4;
239  else if (ape->fileversion >= 3900 || (ape->fileversion >= 3800 && ape->compressiontype >= 4000))
240  ape->blocksperframe = 73728;
241  else
242  ape->blocksperframe = 9216;
243 
244  /* Skip any stored wav header */
246  avio_skip(pb, ape->wavheaderlength);
247  }
248 
249  if(!ape->totalframes){
250  av_log(s, AV_LOG_ERROR, "No frames in the file!\n");
251  return AVERROR(EINVAL);
252  }
253  if(ape->totalframes > UINT_MAX / sizeof(APEFrame)){
254  av_log(s, AV_LOG_ERROR, "Too many frames: %"PRIu32"\n",
255  ape->totalframes);
256  return -1;
257  }
258  if (ape->seektablelength / sizeof(*ape->seektable) < ape->totalframes) {
259  av_log(s, AV_LOG_ERROR,
260  "Number of seek entries is less than number of frames: %zu vs. %"PRIu32"\n",
261  ape->seektablelength / sizeof(*ape->seektable), ape->totalframes);
262  return AVERROR_INVALIDDATA;
263  }
264  ape->frames = av_malloc(ape->totalframes * sizeof(APEFrame));
265  if(!ape->frames)
266  return AVERROR(ENOMEM);
267  ape->firstframe = ape->junklength + ape->descriptorlength + ape->headerlength + ape->seektablelength + ape->wavheaderlength;
268  ape->currentframe = 0;
269 
270 
271  ape->totalsamples = ape->finalframeblocks;
272  if (ape->totalframes > 1)
273  ape->totalsamples += ape->blocksperframe * (ape->totalframes - 1);
274 
275  if (ape->seektablelength > 0) {
276  ape->seektable = av_malloc(ape->seektablelength);
277  if (!ape->seektable)
278  return AVERROR(ENOMEM);
279  for (i = 0;
280  i < ape->seektablelength / sizeof(uint32_t) && !pb->eof_reached;
281  i++)
282  ape->seektable[i] = avio_rl32(pb);
283  }
284 
285  ape->frames[0].pos = ape->firstframe;
286  ape->frames[0].nblocks = ape->blocksperframe;
287  ape->frames[0].skip = 0;
288  for (i = 1; i < ape->totalframes; i++) {
289  ape->frames[i].pos = ape->seektable[i] + ape->junklength;
290  ape->frames[i].nblocks = ape->blocksperframe;
291  ape->frames[i - 1].size = ape->frames[i].pos - ape->frames[i - 1].pos;
292  ape->frames[i].skip = (ape->frames[i].pos - ape->frames[0].pos) & 3;
293  }
294  ape->frames[ape->totalframes - 1].size = ape->finalframeblocks * 4;
295  ape->frames[ape->totalframes - 1].nblocks = ape->finalframeblocks;
296 
297  for (i = 0; i < ape->totalframes; i++) {
298  if(ape->frames[i].skip){
299  ape->frames[i].pos -= ape->frames[i].skip;
300  ape->frames[i].size += ape->frames[i].skip;
301  }
302  ape->frames[i].size = (ape->frames[i].size + 3) & ~3;
303  }
304 
305 
306  ape_dumpinfo(s, ape);
307 
308  /* try to read APE tags */
309  if (pb->seekable) {
310  ff_ape_parse_tag(s);
311  avio_seek(pb, 0, SEEK_SET);
312  }
313 
314  av_log(s, AV_LOG_DEBUG, "Decoding file - v%d.%02d, compression level %"PRIu16"\n",
315  ape->fileversion / 1000, (ape->fileversion % 1000) / 10,
316  ape->compressiontype);
317 
318  /* now we are ready: build format streams */
319  st = avformat_new_stream(s, NULL);
320  if (!st)
321  return -1;
322 
323  total_blocks = (ape->totalframes == 0) ? 0 : ((ape->totalframes - 1) * ape->blocksperframe) + ape->finalframeblocks;
324 
326  st->codec->codec_id = CODEC_ID_APE;
327  st->codec->codec_tag = MKTAG('A', 'P', 'E', ' ');
328  st->codec->channels = ape->channels;
329  st->codec->sample_rate = ape->samplerate;
330  st->codec->bits_per_coded_sample = ape->bps;
332 
333  st->nb_frames = ape->totalframes;
334  st->start_time = 0;
335  st->duration = total_blocks / MAC_SUBFRAME_SIZE;
337 
340  AV_WL16(st->codec->extradata + 0, ape->fileversion);
341  AV_WL16(st->codec->extradata + 2, ape->compressiontype);
342  AV_WL16(st->codec->extradata + 4, ape->formatflags);
343 
344  pts = 0;
345  for (i = 0; i < ape->totalframes; i++) {
346  ape->frames[i].pts = pts;
347  av_add_index_entry(st, ape->frames[i].pos, ape->frames[i].pts, 0, 0, AVINDEX_KEYFRAME);
348  pts += ape->blocksperframe / MAC_SUBFRAME_SIZE;
349  }
350 
351  return 0;
352 }
353 
355 {
356  int ret;
357  int nblocks;
358  APEContext *ape = s->priv_data;
359  uint32_t extra_size = 8;
360 
361  if (s->pb->eof_reached)
362  return AVERROR(EIO);
363  if (ape->currentframe > ape->totalframes)
364  return AVERROR(EIO);
365 
366  avio_seek (s->pb, ape->frames[ape->currentframe].pos, SEEK_SET);
367 
368  /* Calculate how many blocks there are in this frame */
369  if (ape->currentframe == (ape->totalframes - 1))
370  nblocks = ape->finalframeblocks;
371  else
372  nblocks = ape->blocksperframe;
373 
374  if (av_new_packet(pkt, ape->frames[ape->currentframe].size + extra_size) < 0)
375  return AVERROR(ENOMEM);
376 
377  AV_WL32(pkt->data , nblocks);
378  AV_WL32(pkt->data + 4, ape->frames[ape->currentframe].skip);
379  ret = avio_read(s->pb, pkt->data + extra_size, ape->frames[ape->currentframe].size);
380 
381  pkt->pts = ape->frames[ape->currentframe].pts;
382  pkt->stream_index = 0;
383 
384  /* note: we need to modify the packet size here to handle the last
385  packet */
386  pkt->size = ret + extra_size;
387 
388  ape->currentframe++;
389 
390  return 0;
391 }
392 
394 {
395  APEContext *ape = s->priv_data;
396 
397  av_freep(&ape->frames);
398  av_freep(&ape->seektable);
399  return 0;
400 }
401 
402 static int ape_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
403 {
404  AVStream *st = s->streams[stream_index];
405  APEContext *ape = s->priv_data;
406  int index = av_index_search_timestamp(st, timestamp, flags);
407 
408  if (index < 0)
409  return -1;
410 
411  ape->currentframe = index;
412  return 0;
413 }
414 
416  .name = "ape",
417  .long_name = NULL_IF_CONFIG_SMALL("Monkey's Audio"),
418  .priv_data_size = sizeof(APEContext),
424  .extensions = "ape,apl,mac"
425 };