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mpc.c
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1 /*
2  * Musepack demuxer
3  * Copyright (c) 2006 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 
23 #include "libavcodec/get_bits.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "apetag.h"
27 #include "id3v1.h"
28 #include "libavutil/dict.h"
29 
30 #define MPC_FRAMESIZE 1152
31 #define DELAY_FRAMES 32
32 
33 static const int mpc_rate[4] = { 44100, 48000, 37800, 32000 };
34 typedef struct MPCFrame {
35  int64_t pos;
36  int size, skip;
37 }MPCFrame;
38 
39 typedef struct MPCContext {
40  int ver;
41  uint32_t curframe, lastframe;
42  uint32_t fcount;
44  int curbits;
46 } MPCContext;
47 
48 static int mpc_probe(AVProbeData *p)
49 {
50  const uint8_t *d = p->buf;
51  if (d[0] == 'M' && d[1] == 'P' && d[2] == '+' && (d[3] == 0x17 || d[3] == 0x7))
52  return AVPROBE_SCORE_MAX;
53  return 0;
54 }
55 
57 {
58  MPCContext *c = s->priv_data;
59  AVStream *st;
60 
61  if(avio_rl24(s->pb) != MKTAG('M', 'P', '+', 0)){
62  av_log(s, AV_LOG_ERROR, "Not a Musepack file\n");
63  return AVERROR_INVALIDDATA;
64  }
65  c->ver = avio_r8(s->pb);
66  if(c->ver != 0x07 && c->ver != 0x17){
67  av_log(s, AV_LOG_ERROR, "Can demux Musepack SV7, got version %02X\n", c->ver);
68  return AVERROR_INVALIDDATA;
69  }
70  c->fcount = avio_rl32(s->pb);
71  if((int64_t)c->fcount * sizeof(MPCFrame) >= UINT_MAX){
72  av_log(s, AV_LOG_ERROR, "Too many frames, seeking is not possible\n");
73  return AVERROR_INVALIDDATA;
74  }
75  if(c->fcount){
76  c->frames = av_malloc(c->fcount * sizeof(MPCFrame));
77  if(!c->frames){
78  av_log(s, AV_LOG_ERROR, "Cannot allocate seektable\n");
79  return AVERROR(ENOMEM);
80  }
81  }else{
82  av_log(s, AV_LOG_WARNING, "Container reports no frames\n");
83  }
84  c->curframe = 0;
85  c->lastframe = -1;
86  c->curbits = 8;
87  c->frames_noted = 0;
88 
89  st = avformat_new_stream(s, NULL);
90  if (!st)
91  return AVERROR(ENOMEM);
94  st->codec->channels = 2;
96  st->codec->bits_per_coded_sample = 16;
97 
98  if (ff_get_extradata(st->codec, s->pb, 16) < 0)
99  return AVERROR(ENOMEM);
100  st->codec->sample_rate = mpc_rate[st->codec->extradata[2] & 3];
102  /* scan for seekpoints */
103  st->start_time = 0;
104  st->duration = c->fcount;
105 
106  /* try to read APE tags */
107  if (s->pb->seekable) {
108  int64_t pos = avio_tell(s->pb);
109  ff_ape_parse_tag(s);
111  ff_id3v1_read(s);
112  avio_seek(s->pb, pos, SEEK_SET);
113  }
114 
115  return 0;
116 }
117 
119 {
120  MPCContext *c = s->priv_data;
121  int ret, size, size2, curbits, cur = c->curframe;
122  unsigned tmp;
123  int64_t pos;
124 
125  if (c->curframe >= c->fcount && c->fcount)
126  return AVERROR_EOF;
127 
128  if(c->curframe != c->lastframe + 1){
129  avio_seek(s->pb, c->frames[c->curframe].pos, SEEK_SET);
130  c->curbits = c->frames[c->curframe].skip;
131  }
132  c->lastframe = c->curframe;
133  c->curframe++;
134  curbits = c->curbits;
135  pos = avio_tell(s->pb);
136  tmp = avio_rl32(s->pb);
137  if(curbits <= 12){
138  size2 = (tmp >> (12 - curbits)) & 0xFFFFF;
139  }else{
140  size2 = (tmp << (curbits - 12) | avio_rl32(s->pb) >> (44 - curbits)) & 0xFFFFF;
141  }
142  curbits += 20;
143  avio_seek(s->pb, pos, SEEK_SET);
144 
145  size = ((size2 + curbits + 31) & ~31) >> 3;
146  if(cur == c->frames_noted && c->fcount){
147  c->frames[cur].pos = pos;
148  c->frames[cur].size = size;
149  c->frames[cur].skip = curbits - 20;
150  av_add_index_entry(s->streams[0], cur, cur, size, 0, AVINDEX_KEYFRAME);
151  c->frames_noted++;
152  }
153  c->curbits = (curbits + size2) & 0x1F;
154 
155  if ((ret = av_new_packet(pkt, size + 4)) < 0)
156  return ret;
157 
158  pkt->data[0] = curbits;
159  pkt->data[1] = (c->curframe > c->fcount) && c->fcount;
160  pkt->data[2] = 0;
161  pkt->data[3] = 0;
162 
163  pkt->stream_index = 0;
164  pkt->pts = cur;
165  ret = avio_read(s->pb, pkt->data + 4, size);
166  if(c->curbits)
167  avio_seek(s->pb, -4, SEEK_CUR);
168  if(ret < size){
169  av_packet_unref(pkt);
170  return ret < 0 ? ret : AVERROR(EIO);
171  }
172  pkt->size = ret + 4;
173 
174  return 0;
175 }
176 
178 {
179  MPCContext *c = s->priv_data;
180 
181  av_freep(&c->frames);
182  return 0;
183 }
184 
185 /**
186  * Seek to the given position
187  * If position is unknown but is within the limits of file
188  * then packets are skipped unless desired position is reached
189  *
190  * Also this function makes use of the fact that timestamp == frameno
191  */
192 static int mpc_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
193 {
194  AVStream *st = s->streams[stream_index];
195  MPCContext *c = s->priv_data;
196  AVPacket pkt1, *pkt = &pkt1;
197  int ret;
198  int index = av_index_search_timestamp(st, FFMAX(timestamp - DELAY_FRAMES, 0), flags);
199  uint32_t lastframe;
200 
201  /* if found, seek there */
202  if (index >= 0 && st->index_entries[st->nb_index_entries-1].timestamp >= timestamp - DELAY_FRAMES){
203  c->curframe = st->index_entries[index].pos;
204  return 0;
205  }
206  /* if timestamp is out of bounds, return error */
207  if(timestamp < 0 || timestamp >= c->fcount)
208  return -1;
209  timestamp -= DELAY_FRAMES;
210  /* seek to the furthest known position and read packets until
211  we reach desired position */
212  lastframe = c->curframe;
213  if(c->frames_noted) c->curframe = c->frames_noted - 1;
214  while(c->curframe < timestamp){
215  ret = av_read_frame(s, pkt);
216  if (ret < 0){
217  c->curframe = lastframe;
218  return ret;
219  }
220  av_packet_unref(pkt);
221  }
222  return 0;
223 }
224 
225 
227  .name = "mpc",
228  .long_name = NULL_IF_CONFIG_SMALL("Musepack"),
229  .priv_data_size = sizeof(MPCContext),
235  .extensions = "mpc",
236 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
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:1776
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
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:4147
int64_t pos
Definition: avformat.h:817
int ff_get_extradata(AVCodecContext *avctx, 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:2998
uint32_t fcount
Definition: mpc.c:42
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:235
int size
Definition: avcodec.h:1468
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:208
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1080
static AVPacket pkt
#define AV_CH_LAYOUT_STEREO
Format I/O context.
Definition: avformat.h:1314
Public dictionary API.
static int mpc_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mpc.c:118
uint8_t
#define av_malloc(s)
static int mpc_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Seek to the given position If position is unknown but is within the limits of file then packets are s...
Definition: mpc.c:192
static int mpc_read_close(AVFormatContext *s)
Definition: mpc.c:177
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1647
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3803
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1382
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:39
uint8_t * data
Definition: avcodec.h:1467
#define AVERROR_EOF
End of file.
Definition: error.h:55
bitstream reader API header.
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:442
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2917
uint32_t lastframe
Definition: mpc.c:41
static const int mpc_rate[4]
Definition: mpc.c:33
MPCFrame * frames
Definition: mpc.c:43
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:545
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
#define AVINDEX_KEYFRAME
Definition: avformat.h:824
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1528
int frames_noted
Definition: mpc.c:45
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:1875
int size
Definition: mpc.c:36
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:667
#define AVERROR(e)
Definition: error.h:43
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:818
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
#define DELAY_FRAMES
Definition: mpc.c:31
#define FFMAX(a, b)
Definition: common.h:94
int64_t ff_ape_parse_tag(AVFormatContext *s)
Read and parse an APE tag.
Definition: apetag.c:118
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2338
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:536
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:896
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:462
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:207
audio channel layout utility functions
uint32_t curframe
Definition: mpc.c:41
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
int skip
Definition: mpc.c:36
AVInputFormat ff_mpc_demuxer
Definition: mpc.c:226
#define MPC_FRAMESIZE
Definition: mpc.c:30
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:638
Stream structure.
Definition: avformat.h:877
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
int64_t pos
Definition: mpc.c:35
enum AVMediaType codec_type
Definition: avcodec.h:1540
enum AVCodecID codec_id
Definition: avcodec.h:1549
int sample_rate
samples per second
Definition: avcodec.h:2287
AVIOContext * pb
I/O context.
Definition: avformat.h:1356
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:545
int nb_index_entries
Definition: avformat.h:1082
int index
Definition: gxfenc.c:89
Definition: mpc.c:34
This structure contains the data a format has to probe a file.
Definition: avformat.h:460
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1507
static int flags
Definition: cpu.c:47
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:936
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:472
Main libavformat public API header.
static int mpc_read_header(AVFormatContext *s)
Definition: mpc.c:56
int curbits
Definition: mpc.c:44
static int mpc_probe(AVProbeData *p)
Definition: mpc.c:48
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:929
static double c[64]
int channels
number of audio channels
Definition: avcodec.h:2288
int frames
Definition: mpc.h:63
void * priv_data
Format private data.
Definition: avformat.h:1342
#define av_freep(p)
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key, ignoring the suffix of the found key string.
Definition: dict.h:72
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:659
int stream_index
Definition: avcodec.h:1469
#define MKTAG(a, b, c, d)
Definition: common.h:342
This structure stores compressed data.
Definition: avcodec.h:1444
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1460
Definition: mpc.h:52
int ver
Definition: mpc.c:40