FFmpeg  4.4.6
xwma.c
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1 /*
2  * xWMA demuxer
3  * Copyright (c) 2011 Max Horn
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 <inttypes.h>
23 #include <stdint.h>
24 
25 #include "avformat.h"
26 #include "internal.h"
27 #include "riff.h"
28 
29 /*
30  * Demuxer for xWMA, a Microsoft audio container used by XAudio 2.
31  */
32 
33 typedef struct XWMAContext {
35 } XWMAContext;
36 
37 static int xwma_probe(const AVProbeData *p)
38 {
39  if (!memcmp(p->buf, "RIFF", 4) && !memcmp(p->buf + 8, "XWMA", 4))
40  return AVPROBE_SCORE_MAX;
41  return 0;
42 }
43 
45 {
46  int64_t size;
47  int ret = 0;
48  uint32_t dpds_table_size = 0;
49  uint32_t *dpds_table = NULL;
50  unsigned int tag;
51  AVIOContext *pb = s->pb;
52  AVStream *st;
53  XWMAContext *xwma = s->priv_data;
54  int i;
55 
56  /* The following code is mostly copied from wav.c, with some
57  * minor alterations.
58  */
59 
60  /* check RIFF header */
61  tag = avio_rl32(pb);
62  if (tag != MKTAG('R', 'I', 'F', 'F'))
63  return AVERROR_INVALIDDATA;
64  avio_rl32(pb); /* file size */
65  tag = avio_rl32(pb);
66  if (tag != MKTAG('X', 'W', 'M', 'A'))
67  return AVERROR_INVALIDDATA;
68 
69  /* parse fmt header */
70  tag = avio_rl32(pb);
71  if (tag != MKTAG('f', 'm', 't', ' '))
72  return AVERROR_INVALIDDATA;
73  size = avio_rl32(pb);
74  st = avformat_new_stream(s, NULL);
75  if (!st)
76  return AVERROR(ENOMEM);
77 
78  ret = ff_get_wav_header(s, pb, st->codecpar, size, 0);
79  if (ret < 0)
80  return ret;
82 
83  /* XWMA encoder only allows a few channel/sample rate/bitrate combinations,
84  * but some create identical files with fake bitrate (1ch 22050hz at
85  * 20/48/192kbps are all 20kbps, with the exact same codec data).
86  * Decoder needs correct bitrate to work, so it's normalized here. */
87  if (st->codecpar->codec_id == AV_CODEC_ID_WMAV2) {
88  int ch = st->codecpar->channels;
89  int sr = st->codecpar->sample_rate;
90  int br = st->codecpar->bit_rate;
91 
92  if (ch == 1) {
93  if (sr == 22050 && (br==48000 || br==192000))
94  br = 20000;
95  else if (sr == 32000 && (br==48000 || br==192000))
96  br = 20000;
97  else if (sr == 44100 && (br==96000 || br==192000))
98  br = 48000;
99  }
100  else if (ch == 2) {
101  if (sr == 22050 && (br==48000 || br==192000))
102  br = 32000;
103  else if (sr == 32000 && (br==192000))
104  br = 48000;
105  }
106 
107  st->codecpar->bit_rate = br;
108  }
109 
110  /* Normally xWMA can only contain WMAv2 with 1/2 channels,
111  * and WMAPRO with 6 channels. */
112  if (st->codecpar->codec_id != AV_CODEC_ID_WMAV2 &&
114  avpriv_request_sample(s, "Unexpected codec (tag %s; id %d)",
116  st->codecpar->codec_id);
117  } else {
118  /* xWMA shouldn't have extradata. But the WMA codecs require it,
119  * so we provide our own fake extradata.
120  *
121  * First, check that there really was no extradata in the header. If
122  * there was, then try to use it, after asking the user to provide a
123  * sample of this unusual file.
124  */
125  if (st->codecpar->extradata_size != 0) {
126  /* Surprise, surprise: We *did* get some extradata. No idea
127  * if it will work, but just go on and try it, after asking
128  * the user for a sample.
129  */
130  avpriv_request_sample(s, "Unexpected extradata (%d bytes)",
131  st->codecpar->extradata_size);
132  } else if (st->codecpar->codec_id == AV_CODEC_ID_WMAPRO) {
133  if ((ret = ff_alloc_extradata(st->codecpar, 18)) < 0)
134  return ret;
135 
136  memset(st->codecpar->extradata, 0, st->codecpar->extradata_size);
138  st->codecpar->extradata[14] = 224;
139  } else {
140  if ((ret = ff_alloc_extradata(st->codecpar, 6)) < 0)
141  return ret;
142 
143  memset(st->codecpar->extradata, 0, st->codecpar->extradata_size);
144  /* setup extradata with our experimentally obtained value */
145  st->codecpar->extradata[4] = 31;
146  }
147  }
148 
149  if (!st->codecpar->channels) {
150  av_log(s, AV_LOG_WARNING, "Invalid channel count: %d\n",
151  st->codecpar->channels);
152  return AVERROR_INVALIDDATA;
153  }
155  av_log(s, AV_LOG_WARNING, "Invalid bits_per_coded_sample: %d\n",
157  return AVERROR_INVALIDDATA;
158  }
159 
160  /* set the sample rate */
161  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
162 
163  /* parse the remaining RIFF chunks */
164  for (;;) {
165  if (pb->eof_reached) {
166  ret = AVERROR_EOF;
167  goto fail;
168  }
169  /* read next chunk tag */
170  tag = avio_rl32(pb);
171  size = avio_rl32(pb);
172  if (tag == MKTAG('d', 'a', 't', 'a')) {
173  /* We assume that the data chunk comes last. */
174  break;
175  } else if (tag == MKTAG('d','p','d','s')) {
176  /* Quoting the MSDN xWMA docs on the dpds chunk: "Contains the
177  * decoded packet cumulative data size array, each element is the
178  * number of bytes accumulated after the corresponding xWMA packet
179  * is decoded in order."
180  *
181  * Each packet has size equal to st->codecpar->block_align, which in
182  * all cases I saw so far was always 2230. Thus, we can use the
183  * dpds data to compute a seeking index.
184  */
185 
186  /* Error out if there is more than one dpds chunk. */
187  if (dpds_table) {
188  av_log(s, AV_LOG_ERROR, "two dpds chunks present\n");
189  ret = AVERROR_INVALIDDATA;
190  goto fail;
191  }
192 
193  /* Compute the number of entries in the dpds chunk. */
194  if (size & 3) { /* Size should be divisible by four */
196  "dpds chunk size %"PRId64" not divisible by 4\n", size);
197  }
198  dpds_table_size = size / 4;
199  if (dpds_table_size == 0 || dpds_table_size >= INT_MAX / 4) {
201  "dpds chunk size %"PRId64" invalid\n", size);
202  return AVERROR_INVALIDDATA;
203  }
204 
205  /* Allocate some temporary storage to keep the dpds data around.
206  * for processing later on.
207  */
208  dpds_table = av_malloc_array(dpds_table_size, sizeof(uint32_t));
209  if (!dpds_table) {
210  return AVERROR(ENOMEM);
211  }
212 
213  for (i = 0; i < dpds_table_size; ++i) {
214  if (avio_feof(pb)) {
215  ret = AVERROR_INVALIDDATA;
216  goto fail;
217  }
218  dpds_table[i] = avio_rl32(pb);
219  size -= 4;
220  }
221  }
222  avio_skip(pb, size);
223  }
224 
225  /* Determine overall data length */
226  if (size < 0) {
227  ret = AVERROR_INVALIDDATA;
228  goto fail;
229  }
230  if (!size) {
231  xwma->data_end = INT64_MAX;
232  } else
233  xwma->data_end = avio_tell(pb) + size;
234 
235 
236  if (dpds_table && dpds_table_size) {
237  int64_t cur_pos;
238  const uint32_t bytes_per_sample
239  = (st->codecpar->channels * st->codecpar->bits_per_coded_sample) >> 3;
240 
241  /* Estimate the duration from the total number of output bytes. */
242  const uint64_t total_decoded_bytes = dpds_table[dpds_table_size - 1];
243 
244  if (!bytes_per_sample) {
246  "Invalid bits_per_coded_sample %d for %d channels\n",
248  ret = AVERROR_INVALIDDATA;
249  goto fail;
250  }
251 
252  st->duration = total_decoded_bytes / bytes_per_sample;
253 
254  /* Use the dpds data to build a seek table. We can only do this after
255  * we know the offset to the data chunk, as we need that to determine
256  * the actual offset to each input block.
257  * Note: If we allowed ourselves to assume that the data chunk always
258  * follows immediately after the dpds block, we could of course guess
259  * the data block's start offset already while reading the dpds chunk.
260  * I decided against that, just in case other chunks ever are
261  * discovered.
262  */
263  cur_pos = avio_tell(pb);
264  for (i = 0; i < dpds_table_size; ++i) {
265  /* From the number of output bytes that would accumulate in the
266  * output buffer after decoding the first (i+1) packets, we compute
267  * an offset / timestamp pair.
268  */
270  cur_pos + (i+1) * st->codecpar->block_align, /* pos */
271  dpds_table[i] / bytes_per_sample, /* timestamp */
272  st->codecpar->block_align, /* size */
273  0, /* duration */
275  }
276  } else if (st->codecpar->bit_rate) {
277  /* No dpds chunk was present (or only an empty one), so estimate
278  * the total duration using the average bits per sample and the
279  * total data length.
280  */
281  st->duration = av_rescale((size<<3), st->codecpar->sample_rate, st->codecpar->bit_rate);
282  }
283 
284 fail:
285  av_free(dpds_table);
286 
287  return ret;
288 }
289 
291 {
292  int ret, size;
293  int64_t left;
294  AVStream *st;
295  XWMAContext *xwma = s->priv_data;
296 
297  st = s->streams[0];
298 
299  left = xwma->data_end - avio_tell(s->pb);
300  if (left <= 0) {
301  return AVERROR_EOF;
302  }
303 
304  /* read a single block; the default block size is 2230. */
305  size = (st->codecpar->block_align > 1) ? st->codecpar->block_align : 2230;
306  size = FFMIN(size, left);
307 
308  ret = av_get_packet(s->pb, pkt, size);
309  if (ret < 0)
310  return ret;
311 
312  pkt->stream_index = 0;
313  return ret;
314 }
315 
317  .name = "xwma",
318  .long_name = NULL_IF_CONFIG_SMALL("Microsoft xWMA"),
319  .priv_data_size = sizeof(XWMAContext),
323 };
Main libavformat public API header.
#define AVINDEX_KEYFRAME
Definition: avformat.h:811
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
@ AVSTREAM_PARSE_NONE
Definition: avformat.h:793
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:364
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:750
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
#define s(width, name)
Definition: cbs_vp9.c:257
#define fail()
Definition: checkasm.h:133
#define FFMIN(a, b)
Definition: common.h:105
#define MKTAG(a, b, c, d)
Definition: common.h:478
#define NULL
Definition: coverity.c:32
long long int64_t
Definition: coverity.c:34
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
@ AV_CODEC_ID_WMAV2
Definition: codec_id.h:432
@ AV_CODEC_ID_WMAPRO
Definition: codec_id.h:461
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: utils.c:2013
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
int64_t av_rescale(int64_t a, int64_t b, int64_t c)
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:129
#define av_fourcc2str(fourcc)
Definition: avutil.h:348
int i
Definition: input.c:407
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4945
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0.
Definition: utils.c:3314
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
uint32_t tag
Definition: movenc.c:1611
internal header for RIFF based (de)muxers do NOT include this in end user applications
int ff_get_wav_header(AVFormatContext *s, AVIOContext *pb, AVCodecParameters *par, int size, int big_endian)
Definition: riffdec.c:91
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
int channels
Audio only.
Definition: codec_par.h:166
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
int block_align
Audio only.
Definition: codec_par.h:177
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
int eof_reached
true if was unable to read due to error or eof
Definition: avio.h:239
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
enum AVStreamParseType need_parsing
Definition: avformat.h:1081
int64_t data_end
Definition: xwma.c:34
#define av_free(p)
#define av_malloc_array(a, b)
#define avpriv_request_sample(...)
#define av_log(a,...)
AVPacket * pkt
Definition: movenc.c:59
int size
static int xwma_read_header(AVFormatContext *s)
Definition: xwma.c:44
static int xwma_probe(const AVProbeData *p)
Definition: xwma.c:37
AVInputFormat ff_xwma_demuxer
Definition: xwma.c:316
static int xwma_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: xwma.c:290