FFmpeg
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 "demux.h"
27 #include "internal.h"
28 #include "riff.h"
29 
30 /*
31  * Demuxer for xWMA, a Microsoft audio container used by XAudio 2.
32  */
33 
34 typedef struct XWMAContext {
36 } XWMAContext;
37 
38 static int xwma_probe(const AVProbeData *p)
39 {
40  if (!memcmp(p->buf, "RIFF", 4) && !memcmp(p->buf + 8, "XWMA", 4))
41  return AVPROBE_SCORE_MAX;
42  return 0;
43 }
44 
46 {
47  int64_t size;
48  int ret = 0;
49  uint32_t dpds_table_size = 0;
50  uint32_t *dpds_table = NULL;
51  unsigned int tag;
52  AVIOContext *pb = s->pb;
53  AVStream *st;
54  XWMAContext *xwma = s->priv_data;
55  int i;
56 
57  /* The following code is mostly copied from wav.c, with some
58  * minor alterations.
59  */
60 
61  /* check RIFF header */
62  tag = avio_rl32(pb);
63  if (tag != MKTAG('R', 'I', 'F', 'F'))
64  return AVERROR_INVALIDDATA;
65  avio_rl32(pb); /* file size */
66  tag = avio_rl32(pb);
67  if (tag != MKTAG('X', 'W', 'M', 'A'))
68  return AVERROR_INVALIDDATA;
69 
70  /* parse fmt header */
71  tag = avio_rl32(pb);
72  if (tag != MKTAG('f', 'm', 't', ' '))
73  return AVERROR_INVALIDDATA;
74  size = avio_rl32(pb);
75  st = avformat_new_stream(s, NULL);
76  if (!st)
77  return AVERROR(ENOMEM);
78 
79  ret = ff_get_wav_header(s, pb, st->codecpar, size, 0);
80  if (ret < 0)
81  return ret;
83 
84  /* XWMA encoder only allows a few channel/sample rate/bitrate combinations,
85  * but some create identical files with fake bitrate (1ch 22050hz at
86  * 20/48/192kbps are all 20kbps, with the exact same codec data).
87  * Decoder needs correct bitrate to work, so it's normalized here. */
88  if (st->codecpar->codec_id == AV_CODEC_ID_WMAV2) {
89  int ch = st->codecpar->ch_layout.nb_channels;
90  int sr = st->codecpar->sample_rate;
91  int br = st->codecpar->bit_rate;
92 
93  if (ch == 1) {
94  if (sr == 22050 && (br==48000 || br==192000))
95  br = 20000;
96  else if (sr == 32000 && (br==48000 || br==192000))
97  br = 20000;
98  else if (sr == 44100 && (br==96000 || br==192000))
99  br = 48000;
100  }
101  else if (ch == 2) {
102  if (sr == 22050 && (br==48000 || br==192000))
103  br = 32000;
104  else if (sr == 32000 && (br==192000))
105  br = 48000;
106  }
107 
108  st->codecpar->bit_rate = br;
109  }
110 
111  /* Normally xWMA can only contain WMAv2 with 1/2 channels,
112  * and WMAPRO with 6 channels. */
113  if (st->codecpar->codec_id != AV_CODEC_ID_WMAV2 &&
115  avpriv_request_sample(s, "Unexpected codec (tag %s; id %d)",
117  st->codecpar->codec_id);
118  } else {
119  /* xWMA shouldn't have extradata. But the WMA codecs require it,
120  * so we provide our own fake extradata.
121  *
122  * First, check that there really was no extradata in the header. If
123  * there was, then try to use it, after asking the user to provide a
124  * sample of this unusual file.
125  */
126  if (st->codecpar->extradata_size != 0) {
127  /* Surprise, surprise: We *did* get some extradata. No idea
128  * if it will work, but just go on and try it, after asking
129  * the user for a sample.
130  */
131  avpriv_request_sample(s, "Unexpected extradata (%d bytes)",
132  st->codecpar->extradata_size);
133  } else if (st->codecpar->codec_id == AV_CODEC_ID_WMAPRO) {
134  if ((ret = ff_alloc_extradata(st->codecpar, 18)) < 0)
135  return ret;
136 
137  memset(st->codecpar->extradata, 0, st->codecpar->extradata_size);
139  st->codecpar->extradata[14] = 224;
140  } else {
141  if ((ret = ff_alloc_extradata(st->codecpar, 6)) < 0)
142  return ret;
143 
144  memset(st->codecpar->extradata, 0, st->codecpar->extradata_size);
145  /* setup extradata with our experimentally obtained value */
146  st->codecpar->extradata[4] = 31;
147  }
148  }
149 
151  av_log(s, AV_LOG_WARNING, "Invalid channel count: %d\n",
153  return AVERROR_INVALIDDATA;
154  }
156  av_log(s, AV_LOG_WARNING, "Invalid bits_per_coded_sample: %d\n",
158  return AVERROR_INVALIDDATA;
159  }
160 
161  /* set the sample rate */
162  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
163 
164  /* parse the remaining RIFF chunks */
165  for (;;) {
166  if (pb->eof_reached) {
167  ret = AVERROR_EOF;
168  goto fail;
169  }
170  /* read next chunk tag */
171  tag = avio_rl32(pb);
172  size = avio_rl32(pb);
173  if (tag == MKTAG('d', 'a', 't', 'a')) {
174  /* We assume that the data chunk comes last. */
175  break;
176  } else if (tag == MKTAG('d','p','d','s')) {
177  /* Quoting the MSDN xWMA docs on the dpds chunk: "Contains the
178  * decoded packet cumulative data size array, each element is the
179  * number of bytes accumulated after the corresponding xWMA packet
180  * is decoded in order."
181  *
182  * Each packet has size equal to st->codecpar->block_align, which in
183  * all cases I saw so far was always 2230. Thus, we can use the
184  * dpds data to compute a seeking index.
185  */
186 
187  /* Error out if there is more than one dpds chunk. */
188  if (dpds_table) {
189  av_log(s, AV_LOG_ERROR, "two dpds chunks present\n");
191  goto fail;
192  }
193 
194  /* Compute the number of entries in the dpds chunk. */
195  if (size & 3) { /* Size should be divisible by four */
197  "dpds chunk size %"PRId64" not divisible by 4\n", size);
198  }
199  dpds_table_size = size / 4;
200  if (dpds_table_size == 0 || dpds_table_size >= INT_MAX / 4) {
202  "dpds chunk size %"PRId64" invalid\n", size);
203  return AVERROR_INVALIDDATA;
204  }
205 
206  /* Allocate some temporary storage to keep the dpds data around.
207  * for processing later on.
208  */
209  dpds_table = av_malloc_array(dpds_table_size, sizeof(uint32_t));
210  if (!dpds_table) {
211  return AVERROR(ENOMEM);
212  }
213 
214  for (i = 0; i < dpds_table_size; ++i) {
215  if (avio_feof(pb)) {
217  goto fail;
218  }
219  dpds_table[i] = avio_rl32(pb);
220  size -= 4;
221  }
222  }
223  avio_skip(pb, size);
224  }
225 
226  /* Determine overall data length */
227  if (size < 0) {
229  goto fail;
230  }
231  if (!size) {
232  xwma->data_end = INT64_MAX;
233  } else
234  xwma->data_end = avio_tell(pb) + size;
235 
236 
237  if (dpds_table && dpds_table_size) {
238  int64_t cur_pos;
239  const uint32_t bytes_per_sample
241 
242  /* Estimate the duration from the total number of output bytes. */
243  const uint64_t total_decoded_bytes = dpds_table[dpds_table_size - 1];
244 
245  if (!bytes_per_sample) {
247  "Invalid bits_per_coded_sample %d for %d channels\n",
250  goto fail;
251  }
252 
253  st->duration = total_decoded_bytes / bytes_per_sample;
254 
255  /* Use the dpds data to build a seek table. We can only do this after
256  * we know the offset to the data chunk, as we need that to determine
257  * the actual offset to each input block.
258  * Note: If we allowed ourselves to assume that the data chunk always
259  * follows immediately after the dpds block, we could of course guess
260  * the data block's start offset already while reading the dpds chunk.
261  * I decided against that, just in case other chunks ever are
262  * discovered.
263  */
264  cur_pos = avio_tell(pb);
265  for (i = 0; i < dpds_table_size; ++i) {
266  /* From the number of output bytes that would accumulate in the
267  * output buffer after decoding the first (i+1) packets, we compute
268  * an offset / timestamp pair.
269  */
271  cur_pos + (i+1) * st->codecpar->block_align, /* pos */
272  dpds_table[i] / bytes_per_sample, /* timestamp */
273  st->codecpar->block_align, /* size */
274  0, /* duration */
276  }
277  } else if (st->codecpar->bit_rate) {
278  /* No dpds chunk was present (or only an empty one), so estimate
279  * the total duration using the average bits per sample and the
280  * total data length.
281  */
282  st->duration = av_rescale((size<<3), st->codecpar->sample_rate, st->codecpar->bit_rate);
283  }
284 
285 fail:
286  av_free(dpds_table);
287 
288  return ret;
289 }
290 
292 {
293  int ret, size;
294  int64_t left;
295  AVStream *st;
296  XWMAContext *xwma = s->priv_data;
297 
298  st = s->streams[0];
299 
300  left = xwma->data_end - avio_tell(s->pb);
301  if (left <= 0) {
302  return AVERROR_EOF;
303  }
304 
305  /* read a single block; the default block size is 2230. */
306  size = (st->codecpar->block_align > 1) ? st->codecpar->block_align : 2230;
307  size = FFMIN(size, left);
308 
309  ret = av_get_packet(s->pb, pkt, size);
310  if (ret < 0)
311  return ret;
312 
313  pkt->stream_index = 0;
314  return ret;
315 }
316 
318  .p.name = "xwma",
319  .p.long_name = NULL_IF_CONFIG_SMALL("Microsoft xWMA"),
320  .priv_data_size = sizeof(XWMAContext),
324 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
int64_t
long long int64_t
Definition: coverity.c:34
ff_get_wav_header
int ff_get_wav_header(void *logctx, AVIOContext *pb, AVCodecParameters *par, int size, int big_endian)
Definition: riffdec.c:94
AV_CODEC_ID_WMAV2
@ AV_CODEC_ID_WMAV2
Definition: codec_id.h:448
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:59
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:313
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:610
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:853
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:417
fail
#define fail()
Definition: checkasm.h:179
av_add_index_entry
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: seek.c:120
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
xwma_read_packet
static int xwma_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: xwma.c:291
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:802
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
s
#define s(width, name)
Definition: cbs_vp9.c:198
AV_CODEC_ID_WMAPRO
@ AV_CODEC_ID_WMAPRO
Definition: codec_id.h:477
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:386
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
NULL
#define NULL
Definition: coverity.c:32
AVSTREAM_PARSE_NONE
@ AVSTREAM_PARSE_NONE
Definition: avformat.h:592
XWMAContext
Definition: xwma.c:34
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:73
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:729
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:106
size
int size
Definition: twinvq_data.h:10344
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:191
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:31
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
demux.h
xwma_probe
static int xwma_probe(const AVProbeData *p)
Definition: xwma.c:38
av_rescale
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
av_get_packet
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:103
ff_xwma_demuxer
const FFInputFormat ff_xwma_demuxer
Definition: xwma.c:317
tag
uint32_t tag
Definition: movenc.c:1791
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
av_channel_layout_check
int av_channel_layout_check(const AVChannelLayout *channel_layout)
Check whether a channel layout is valid, i.e.
Definition: channel_layout.c:774
avformat.h
left
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2] ... the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so ...,+,-,+,-,+,+,-,+,-,+,... hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32 - hcoeff[1] - hcoeff[2] - ... a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2} an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||......... intra?||||:Block01 :yes no||||:Block02 :....... ..........||||:Block03 ::y DC ::ref index:||||:Block04 ::cb DC ::motion x :||||......... :cr DC ::motion y :||||....... ..........|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------ ------------ ------------|||Y subbands||Cb subbands||Cr subbands||||--- ---||--- ---||--- ---|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------ ------------ ------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction ------------|\ Dequantization ------------------- \||Reference frames|\ IDWT|------- -------|Motion \|||Frame 0||Frame 1||Compensation . OBMC v -------|------- -------|--------------. \------> Frame n output Frame Frame<----------------------------------/|...|------------------- Range Coder:============Binary Range Coder:------------------- The implemented range coder is an adapted version based upon "Range encoding: an algorithm for removing redundancy from a digitised message." by G. N. N. Martin. The symbols encoded by the Snow range coder are bits(0|1). The associated probabilities are not fix but change depending on the symbol mix seen so far. bit seen|new state ---------+----------------------------------------------- 0|256 - state_transition_table[256 - old_state];1|state_transition_table[old_state];state_transition_table={ 0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:------------------------- FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1. the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled left
Definition: snow.txt:386
AVIOContext::eof_reached
int eof_reached
true if was unable to read due to error or eof
Definition: avio.h:238
AVPacket::stream_index
int stream_index
Definition: packet.h:524
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:317
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:110
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:499
riff.h
FFInputFormat
Definition: demux.h:37
XWMAContext::data_end
int64_t data_end
Definition: xwma.c:35
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:97
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
xwma_read_header
static int xwma_read_header(AVFormatContext *s)
Definition: xwma.c:45
av_fourcc2str
#define av_fourcc2str(fourcc)
Definition: avutil.h:345
ff_alloc_extradata
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:239
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:345