3 * Copyright (c) 2007 Konstantin Shishkov
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "libavcodec/get_bits.h"
23 #include "libavcodec/unary.h"
27 #include "avio_internal.h"
30 #define MKMPCTAG(a, b) (a | (b << 8))
32 #define TAG_MPCK MKTAG('M','P','C','K')
36 TAG_STREAMHDR
= MKMPCTAG('S','H'),
37 TAG_STREAMEND
= MKMPCTAG('S','E'),
39 TAG_AUDIOPACKET
= MKMPCTAG('A','P'),
41 TAG_SEEKTBLOFF
= MKMPCTAG('S','O'),
42 TAG_SEEKTABLE
= MKMPCTAG('S','T'),
44 TAG_REPLAYGAIN
= MKMPCTAG('R','G'),
45 TAG_ENCINFO
= MKMPCTAG('E','I'),
48 static const int mpc8_rate
[8] = { 44100, 48000, 37800, 32000, -1, -1, -1, -1 };
58 static inline int64_t bs_get_v(const uint8_t **bs
)
76 static int mpc8_probe(AVProbeData
*p
)
78 const uint8_t *bs
= p
->buf
+ 4;
79 const uint8_t *bs_end
= bs
+ p
->buf_size
;
84 if (AV_RL32(p
->buf
) != TAG_MPCK
)
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')
94 if (bs
+ size
- 2 >= bs_end
)
95 return AVPROBE_SCORE_EXTENSION
- 1; // seems to be valid MPC but no header yet
97 if (size
< 11 || size
> 28)
99 if (!AV_RL32(bs
)) //zero CRC is invalid
101 return AVPROBE_SCORE_MAX
;
109 static inline int64_t gb_get_v(GetBitContext
*gb
)
113 while(get_bits1(gb
) && bits
< 64-7){
115 v
|= get_bits(gb
, 7);
119 v
|= get_bits(gb
, 7);
124 static void mpc8_get_chunk_header(AVIOContext
*pb
, int *tag
, int64_t *size
)
128 *tag
= avio_rl16(pb
);
129 *size
= ffio_read_varlen(pb
);
130 *size
-= avio_tell(pb
) - pos
;
133 static void mpc8_parse_seektable(AVFormatContext
*s
, int64_t off
)
135 MPCContext
*c
= s
->priv_data
;
137 int64_t size
, pos
, ppos
[2];
139 int i
, t
, seekd
, ret
;
142 if (s
->nb_streams
== 0) {
143 av_log(s
, AV_LOG_ERROR
, "No stream added before parsing seek table\n");
147 avio_seek(s
->pb
, off
, SEEK_SET
);
148 mpc8_get_chunk_header(s
->pb
, &tag
, &size
);
149 if(tag
!= TAG_SEEKTABLE
){
150 av_log(s
, AV_LOG_ERROR
, "No seek table at given position\n");
153 if (size
> INT_MAX
/10 || size
<=0) {
154 av_log(s
, AV_LOG_ERROR
, "Bad seek table size\n");
157 if(!(buf
= av_malloc(size
+ FF_INPUT_BUFFER_PADDING_SIZE
)))
159 ret
= avio_read(s
->pb
, buf
, size
);
161 av_log(s
, AV_LOG_ERROR
, "seek table truncated\n");
165 memset(buf
+size
, 0, FF_INPUT_BUFFER_PADDING_SIZE
);
167 init_get_bits(&gb
, buf
, size
* 8);
168 size
= gb_get_v(&gb
);
169 if(size
> UINT_MAX
/4 || size
> c
->samples
/1152){
170 av_log(s
, AV_LOG_ERROR
, "Seek table is too big\n");
173 seekd
= get_bits(&gb
, 4);
174 for(i
= 0; i
< 2; i
++){
175 pos
= gb_get_v(&gb
) + c
->header_pos
;
177 av_add_index_entry(s
->streams
[0], pos
, i
, 0, 0, AVINDEX_KEYFRAME
);
179 for(; i
< size
; i
++){
180 t
= get_unary(&gb
, 1, 33) << 12;
181 t
+= get_bits(&gb
, 12);
184 pos
= (t
>> 1) + ppos
[0]*2 - ppos
[1];
185 av_add_index_entry(s
->streams
[0], pos
, i
<< seekd
, 0, 0, AVINDEX_KEYFRAME
);
192 static void mpc8_handle_chunk(AVFormatContext
*s
, int tag
, int64_t chunk_pos
, int64_t size
)
194 AVIOContext
*pb
= s
->pb
;
199 pos
= avio_tell(pb
) + size
;
200 off
= ffio_read_varlen(pb
);
201 mpc8_parse_seektable(s
, chunk_pos
+ off
);
202 avio_seek(pb
, pos
, SEEK_SET
);
209 static int mpc8_read_header(AVFormatContext
*s
)
211 MPCContext
*c
= s
->priv_data
;
212 AVIOContext
*pb
= s
->pb
;
217 c
->header_pos
= avio_tell(pb
);
218 if(avio_rl32(pb
) != TAG_MPCK
){
219 av_log(s
, AV_LOG_ERROR
, "Not a Musepack8 file\n");
220 return AVERROR_INVALIDDATA
;
223 while(!avio_feof(pb
)){
225 mpc8_get_chunk_header(pb
, &tag
, &size
);
226 if(tag
== TAG_STREAMHDR
)
228 mpc8_handle_chunk(s
, tag
, pos
, size
);
230 if(tag
!= TAG_STREAMHDR
){
231 av_log(s
, AV_LOG_ERROR
, "Stream header not found\n");
232 return AVERROR_INVALIDDATA
;
235 avio_skip(pb
, 4); //CRC
236 c
->ver
= avio_r8(pb
);
238 av_log(s
, AV_LOG_ERROR
, "Unknown stream version %d\n", c
->ver
);
239 return AVERROR_PATCHWELCOME
;
241 c
->samples
= ffio_read_varlen(pb
);
242 ffio_read_varlen(pb
); //silence samples at the beginning
244 st
= avformat_new_stream(s
, NULL
);
246 return AVERROR(ENOMEM
);
247 st
->codec
->codec_type
= AVMEDIA_TYPE_AUDIO
;
248 st
->codec
->codec_id
= AV_CODEC_ID_MUSEPACK8
;
249 st
->codec
->bits_per_coded_sample
= 16;
251 if (ff_get_extradata(st
->codec
, pb
, 2) < 0)
252 return AVERROR(ENOMEM
);
254 st
->codec
->channels
= (st
->codec
->extradata
[1] >> 4) + 1;
255 st
->codec
->sample_rate
= mpc8_rate
[st
->codec
->extradata
[0] >> 5];
256 avpriv_set_pts_info(st
, 32, 1152 << (st
->codec
->extradata
[1]&3)*2, st
->codec
->sample_rate
);
258 st
->duration
= c
->samples
/ (1152 << (st
->codec
->extradata
[1]&3)*2);
259 size
-= avio_tell(pb
) - pos
;
264 int64_t pos
= avio_tell(s
->pb
);
265 c
->apetag_start
= ff_ape_parse_tag(s
);
266 avio_seek(s
->pb
, pos
, SEEK_SET
);
272 static int mpc8_read_packet(AVFormatContext
*s
, AVPacket
*pkt
)
274 MPCContext
*c
= s
->priv_data
;
278 while(!avio_feof(s
->pb
)){
279 pos
= avio_tell(s
->pb
);
281 /* don't return bogus packets with the ape tag data */
282 if (c
->apetag_start
&& pos
>= c
->apetag_start
)
285 mpc8_get_chunk_header(s
->pb
, &tag
, &size
);
288 if(tag
== TAG_AUDIOPACKET
){
289 if(av_get_packet(s
->pb
, pkt
, size
) < 0)
290 return AVERROR(ENOMEM
);
291 pkt
->stream_index
= 0;
295 if(tag
== TAG_STREAMEND
)
297 mpc8_handle_chunk(s
, tag
, pos
, size
);
302 static int mpc8_read_seek(AVFormatContext
*s
, int stream_index
, int64_t timestamp
, int flags
)
304 AVStream
*st
= s
->streams
[stream_index
];
305 int index
= av_index_search_timestamp(st
, timestamp
, flags
);
307 if(index
< 0) return -1;
308 if (avio_seek(s
->pb
, st
->index_entries
[index
].pos
, SEEK_SET
) < 0)
310 ff_update_cur_dts(s
, st
, st
->index_entries
[index
].timestamp
);
315 AVInputFormat ff_mpc8_demuxer
= {
317 .long_name
= NULL_IF_CONFIG_SMALL("Musepack SV8"),
318 .priv_data_size
= sizeof(MPCContext
),
319 .read_probe
= mpc8_probe
,
320 .read_header
= mpc8_read_header
,
321 .read_packet
= mpc8_read_packet
,
322 .read_seek
= mpc8_read_seek
,