FFmpeg  4.4
mpc8.c
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1 /*
2  * Musepack SV8 demuxer
3  * Copyright (c) 2007 Konstantin Shishkov
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 "libavcodec/get_bits.h"
23 #include "libavcodec/unary.h"
24 #include "apetag.h"
25 #include "avformat.h"
26 #include "internal.h"
27 #include "avio_internal.h"
28 
29 /// Two-byte MPC tag
30 #define MKMPCTAG(a, b) ((a) | ((b) << 8))
31 
32 #define TAG_MPCK MKTAG('M','P','C','K')
33 
34 /// Reserved MPC tags
36  TAG_STREAMHDR = MKMPCTAG('S','H'),
37  TAG_STREAMEND = MKMPCTAG('S','E'),
38 
40 
42  TAG_SEEKTABLE = MKMPCTAG('S','T'),
43 
45  TAG_ENCINFO = MKMPCTAG('E','I'),
46 };
47 
48 static const int mpc8_rate[8] = { 44100, 48000, 37800, 32000, -1, -1, -1, -1 };
49 
50 typedef struct MPCContext {
51  int ver;
52  int64_t header_pos;
53  int64_t samples;
54 
55  int64_t apetag_start;
56 } MPCContext;
57 
58 static inline int64_t bs_get_v(const uint8_t **bs)
59 {
60  uint64_t v = 0;
61  int br = 0;
62  int c;
63 
64  do {
65  c = **bs; (*bs)++;
66  v <<= 7;
67  v |= c & 0x7F;
68  br++;
69  if (br > 10)
70  return -1;
71  } while (c & 0x80);
72 
73  return v - br;
74 }
75 
76 static int mpc8_probe(const AVProbeData *p)
77 {
78  const uint8_t *bs = p->buf + 4;
79  const uint8_t *bs_end = bs + p->buf_size;
80  int64_t size;
81 
82  if (p->buf_size < 16)
83  return 0;
84  if (AV_RL32(p->buf) != TAG_MPCK)
85  return 0;
86  while (bs < bs_end + 3) {
87  int header_found = (bs[0] == 'S' && bs[1] == 'H');
88  if (bs[0] < 'A' || bs[0] > 'Z' || bs[1] < 'A' || bs[1] > 'Z')
89  return 0;
90  bs += 2;
91  size = bs_get_v(&bs);
92  if (size < 2)
93  return 0;
94  if (size >= bs_end - bs + 2)
95  return AVPROBE_SCORE_EXTENSION - 1; // seems to be valid MPC but no header yet
96  if (header_found) {
97  if (size < 11 || size > 28)
98  return 0;
99  if (!AV_RL32(bs)) //zero CRC is invalid
100  return 0;
101  return AVPROBE_SCORE_MAX;
102  } else {
103  bs += size - 2;
104  }
105  }
106  return 0;
107 }
108 
109 static inline int64_t gb_get_v(GetBitContext *gb)
110 {
111  uint64_t v = 0;
112  int bits = 0;
113  while(get_bits1(gb) && bits < 64-7){
114  v <<= 7;
115  v |= get_bits(gb, 7);
116  bits += 7;
117  }
118  v <<= 7;
119  v |= get_bits(gb, 7);
120 
121  return v;
122 }
123 
124 static void mpc8_get_chunk_header(AVIOContext *pb, int *tag, int64_t *size)
125 {
126  int64_t pos;
127  pos = avio_tell(pb);
128  *tag = avio_rl16(pb);
129  *size = ffio_read_varlen(pb);
130  pos -= avio_tell(pb);
131  if (av_sat_add64(*size, pos) != (uint64_t)*size + pos) {
132  *size = -1;
133  } else
134  *size += pos;
135 }
136 
137 static void mpc8_parse_seektable(AVFormatContext *s, int64_t off)
138 {
139  MPCContext *c = s->priv_data;
140  int tag;
141  int64_t size, pos, ppos[2];
142  uint8_t *buf;
143  int i, t, seekd, ret;
144  GetBitContext gb;
145 
146  if (s->nb_streams == 0) {
147  av_log(s, AV_LOG_ERROR, "No stream added before parsing seek table\n");
148  return;
149  }
150 
151  avio_seek(s->pb, off, SEEK_SET);
152  mpc8_get_chunk_header(s->pb, &tag, &size);
153  if(tag != TAG_SEEKTABLE){
154  av_log(s, AV_LOG_ERROR, "No seek table at given position\n");
155  return;
156  }
157  if (size > INT_MAX/10 || size<=0) {
158  av_log(s, AV_LOG_ERROR, "Bad seek table size\n");
159  return;
160  }
162  return;
163  ret = avio_read(s->pb, buf, size);
164  if (ret != size) {
165  av_log(s, AV_LOG_ERROR, "seek table truncated\n");
166  av_free(buf);
167  return;
168  }
169  memset(buf+size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
170 
171  init_get_bits(&gb, buf, size * 8);
172  size = gb_get_v(&gb);
173  if(size > UINT_MAX/4 || size > c->samples/1152){
174  av_log(s, AV_LOG_ERROR, "Seek table is too big\n");
175  av_free(buf);
176  return;
177  }
178  seekd = get_bits(&gb, 4);
179  for(i = 0; i < 2; i++){
180  pos = gb_get_v(&gb) + c->header_pos;
181  ppos[1 - i] = pos;
182  av_add_index_entry(s->streams[0], pos, i, 0, 0, AVINDEX_KEYFRAME);
183  }
184  for(; i < size; i++){
185  if (get_bits_left(&gb) < 13) {
186  av_free(buf);
187  return;
188  }
189  t = get_unary(&gb, 1, 33) << 12;
190  t += get_bits(&gb, 12);
191  if(t & 1)
192  t = -(t & ~1);
193  pos = (t >> 1) + (uint64_t)ppos[0]*2 - ppos[1];
194  av_add_index_entry(s->streams[0], pos, (int64_t)i << seekd, 0, 0, AVINDEX_KEYFRAME);
195  ppos[1] = ppos[0];
196  ppos[0] = pos;
197  }
198  av_free(buf);
199 }
200 
201 static void mpc8_handle_chunk(AVFormatContext *s, int tag, int64_t chunk_pos, int64_t size)
202 {
203  AVIOContext *pb = s->pb;
204  int64_t pos, off;
205 
206  switch(tag){
207  case TAG_SEEKTBLOFF:
208  pos = avio_tell(pb) + size;
209  off = ffio_read_varlen(pb);
210  mpc8_parse_seektable(s, chunk_pos + off);
211  avio_seek(pb, pos, SEEK_SET);
212  break;
213  default:
214  avio_skip(pb, size);
215  }
216 }
217 
219 {
220  MPCContext *c = s->priv_data;
221  AVIOContext *pb = s->pb;
222  AVStream *st;
223  int tag = 0, ret;
224  int64_t size, pos;
225 
226  c->header_pos = avio_tell(pb);
227  if(avio_rl32(pb) != TAG_MPCK){
228  av_log(s, AV_LOG_ERROR, "Not a Musepack8 file\n");
229  return AVERROR_INVALIDDATA;
230  }
231 
232  while(!avio_feof(pb)){
233  pos = avio_tell(pb);
235  if (size < 0) {
236  av_log(s, AV_LOG_ERROR, "Invalid chunk length\n");
237  return AVERROR_INVALIDDATA;
238  }
239  if(tag == TAG_STREAMHDR)
240  break;
242  }
243  if(tag != TAG_STREAMHDR){
244  av_log(s, AV_LOG_ERROR, "Stream header not found\n");
245  return AVERROR_INVALIDDATA;
246  }
247  pos = avio_tell(pb);
248  avio_skip(pb, 4); //CRC
249  c->ver = avio_r8(pb);
250  if(c->ver != 8){
251  avpriv_report_missing_feature(s, "Stream version %d", c->ver);
252  return AVERROR_PATCHWELCOME;
253  }
254  c->samples = ffio_read_varlen(pb);
255  ffio_read_varlen(pb); //silence samples at the beginning
256 
257  st = avformat_new_stream(s, NULL);
258  if (!st)
259  return AVERROR(ENOMEM);
263 
264  if ((ret = ff_get_extradata(s, st->codecpar, pb, 2)) < 0)
265  return ret;
266 
267  st->codecpar->channels = (st->codecpar->extradata[1] >> 4) + 1;
268  st->codecpar->sample_rate = mpc8_rate[st->codecpar->extradata[0] >> 5];
269  avpriv_set_pts_info(st, 64, 1152 << (st->codecpar->extradata[1]&3)*2, st->codecpar->sample_rate);
270  st->start_time = 0;
271  st->duration = c->samples / (1152 << (st->codecpar->extradata[1]&3)*2);
272  size -= avio_tell(pb) - pos;
273  if (size > 0)
274  avio_skip(pb, size);
275 
276  if (pb->seekable & AVIO_SEEKABLE_NORMAL) {
277  int64_t pos = avio_tell(s->pb);
278  c->apetag_start = ff_ape_parse_tag(s);
279  avio_seek(s->pb, pos, SEEK_SET);
280  }
281 
282  return 0;
283 }
284 
286 {
287  MPCContext *c = s->priv_data;
288  int tag, ret;
289  int64_t pos, size;
290 
291  while(!avio_feof(s->pb)){
292  pos = avio_tell(s->pb);
293 
294  /* don't return bogus packets with the ape tag data */
295  if (c->apetag_start && pos >= c->apetag_start)
296  return AVERROR_EOF;
297 
298  mpc8_get_chunk_header(s->pb, &tag, &size);
299  if (size < 0 || size > INT_MAX)
300  return -1;
301  if(tag == TAG_AUDIOPACKET){
302  if ((ret = av_get_packet(s->pb, pkt, size)) < 0)
303  return ret;
304  pkt->stream_index = 0;
305  pkt->duration = 1;
306  return 0;
307  }
308  if(tag == TAG_STREAMEND)
309  return AVERROR_EOF;
311  }
312  return AVERROR_EOF;
313 }
314 
315 static int mpc8_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
316 {
317  AVStream *st = s->streams[stream_index];
318  int index = av_index_search_timestamp(st, timestamp, flags);
319 
320  if(index < 0) return -1;
321  if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
322  return -1;
324  return 0;
325 }
326 
327 
329  .name = "mpc8",
330  .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
331  .priv_data_size = sizeof(MPCContext),
336 };
int64_t ff_ape_parse_tag(AVFormatContext *s)
Read and parse an APE tag.
Definition: apetag.c:118
uint8_t
Main libavformat public API header.
#define AVINDEX_KEYFRAME
Definition: avformat.h:811
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:451
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
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
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
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:734
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:750
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
uint64_t ffio_read_varlen(AVIOContext *bc)
Definition: aviobuf.c:910
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
#define AV_RL32
Definition: intreadwrite.h:146
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#define s(width, name)
Definition: cbs_vp9.c:257
#define av_sat_add64
Definition: common.h:164
#define NULL
Definition: coverity.c:32
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
bitstream reader API header.
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:849
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:659
@ AV_CODEC_ID_MUSEPACK8
Definition: codec_id.h:458
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding.
Definition: avcodec.h:215
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4505
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:2011
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2128
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
#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_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
int index
Definition: gxfenc.c:89
int i
Definition: input.c:407
void ff_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp)
Update cur_dts of all streams based on the given timestamp and AVStream.
Definition: utils.c:1925
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:4941
int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, AVIOContext *pb, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: utils.c:3330
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
static void mpc8_parse_seektable(AVFormatContext *s, int64_t off)
Definition: mpc8.c:137
static int mpc8_probe(const AVProbeData *p)
Definition: mpc8.c:76
static int mpc8_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mpc8.c:285
AVInputFormat ff_mpc8_demuxer
Definition: mpc8.c:328
static int64_t bs_get_v(const uint8_t **bs)
Definition: mpc8.c:58
#define MKMPCTAG(a, b)
Two-byte MPC tag.
Definition: mpc8.c:30
static int mpc8_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: mpc8.c:315
#define TAG_MPCK
Definition: mpc8.c:32
static const int mpc8_rate[8]
Definition: mpc8.c:48
static void mpc8_get_chunk_header(AVIOContext *pb, int *tag, int64_t *size)
Definition: mpc8.c:124
static void mpc8_handle_chunk(AVFormatContext *s, int tag, int64_t chunk_pos, int64_t size)
Definition: mpc8.c:201
MPCPacketTags
Reserved MPC tags.
Definition: mpc8.c:35
@ TAG_REPLAYGAIN
Definition: mpc8.c:44
@ TAG_AUDIOPACKET
Definition: mpc8.c:39
@ TAG_SEEKTABLE
Definition: mpc8.c:42
@ TAG_SEEKTBLOFF
Definition: mpc8.c:41
@ TAG_STREAMEND
Definition: mpc8.c:37
@ TAG_ENCINFO
Definition: mpc8.c:45
@ TAG_STREAMHDR
Definition: mpc8.c:36
static int64_t gb_get_v(GetBitContext *gb)
Definition: mpc8.c:109
static int mpc8_read_header(AVFormatContext *s)
Definition: mpc8.c:218
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
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
uint32_t tag
Definition: movenc.c:1600
unsigned int pos
Definition: spdifenc.c:412
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
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
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 seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:260
int64_t pos
Definition: avformat.h:804
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:805
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
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:387
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
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
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:912
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1090
Definition: mpc.h:53
int64_t header_pos
Definition: mpc8.c:52
int64_t samples
Definition: mpc8.c:53
int ver
Definition: mpc.c:40
int64_t apetag_start
Definition: mpc8.c:55
#define av_free(p)
#define av_malloc(s)
#define av_log(a,...)
AVPacket * pkt
Definition: movenc.c:59
int size
static int get_unary(GetBitContext *gb, int stop, int len)
Get unary code of limited length.
Definition: unary.h:46
uint8_t bits
Definition: vp3data.h:141
static double c[64]