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 #define MKMPCTAG(a, b) (a | (b << 8))
29 #define TAG_MPCK MKTAG('M','P','C','K')
33 TAG_STREAMHDR
= MKMPCTAG('S','H'),
34 TAG_STREAMEND
= MKMPCTAG('S','E'),
36 TAG_AUDIOPACKET
= MKMPCTAG('A','P'),
38 TAG_SEEKTBLOFF
= MKMPCTAG('S','O'),
39 TAG_SEEKTABLE
= MKMPCTAG('S','T'),
41 TAG_REPLAYGAIN
= MKMPCTAG('R','G'),
42 TAG_ENCINFO
= MKMPCTAG('E','I'),
45 static const int mpc8_rate
[8] = { 44100, 48000, 37800, 32000, -1, -1, -1, -1 };
54 static inline int64_t bs_get_v(uint8_t **bs
)
72 static int mpc8_probe(AVProbeData
*p
)
74 uint8_t *bs
= p
->buf
+ 4;
75 uint8_t *bs_end
= bs
+ p
->buf_size
;
80 if (AV_RL32(p
->buf
) != TAG_MPCK
)
82 while (bs
< bs_end
+ 3) {
83 int header_found
= (bs
[0] == 'S' && bs
[1] == 'H');
84 if (bs
[0] < 'A' || bs
[0] > 'Z' || bs
[1] < 'A' || bs
[1] > 'Z')
90 if (bs
+ size
- 2 >= bs_end
)
91 return AVPROBE_SCORE_MAX
/ 4 - 1; //seems to be valid MPC but no header yet
93 if (size
< 11 || size
> 28)
95 if (!AV_RL32(bs
)) //zero CRC is invalid
97 return AVPROBE_SCORE_MAX
;
105 static inline int64_t gb_get_v(GetBitContext
*gb
)
109 while(get_bits1(gb
) && bits
< 64-7){
111 v
|= get_bits(gb
, 7);
115 v
|= get_bits(gb
, 7);
120 static void mpc8_get_chunk_header(ByteIOContext
*pb
, int *tag
, int64_t *size
)
125 *size
= ff_get_v(pb
);
126 *size
-= url_ftell(pb
) - pos
;
129 static void mpc8_parse_seektable(AVFormatContext
*s
, int64_t off
)
131 MPCContext
*c
= s
->priv_data
;
133 int64_t size
, pos
, ppos
[2];
138 url_fseek(s
->pb
, off
, SEEK_SET
);
139 mpc8_get_chunk_header(s
->pb
, &tag
, &size
);
140 if(tag
!= TAG_SEEKTABLE
){
141 av_log(s
, AV_LOG_ERROR
, "No seek table at given position\n");
144 if(!(buf
= av_malloc(size
+ FF_INPUT_BUFFER_PADDING_SIZE
)))
146 get_buffer(s
->pb
, buf
, size
);
147 init_get_bits(&gb
, buf
, size
* 8);
148 size
= gb_get_v(&gb
);
149 if(size
> UINT_MAX
/4 || size
> c
->samples
/1152){
150 av_log(s
, AV_LOG_ERROR
, "Seek table is too big\n");
153 seekd
= get_bits(&gb
, 4);
154 for(i
= 0; i
< 2; i
++){
155 pos
= gb_get_v(&gb
) + c
->header_pos
;
157 av_add_index_entry(s
->streams
[0], pos
, i
, 0, 0, AVINDEX_KEYFRAME
);
159 for(; i
< size
; i
++){
160 t
= get_unary(&gb
, 1, 33) << 12;
161 t
+= get_bits(&gb
, 12);
164 pos
= (t
>> 1) + ppos
[0]*2 - ppos
[1];
165 av_add_index_entry(s
->streams
[0], pos
, i
<< seekd
, 0, 0, AVINDEX_KEYFRAME
);
172 static void mpc8_handle_chunk(AVFormatContext
*s
, int tag
, int64_t chunk_pos
, int64_t size
)
174 ByteIOContext
*pb
= s
->pb
;
179 pos
= url_ftell(pb
) + size
;
181 mpc8_parse_seektable(s
, chunk_pos
+ off
);
182 url_fseek(pb
, pos
, SEEK_SET
);
189 static int mpc8_read_header(AVFormatContext
*s
, AVFormatParameters
*ap
)
191 MPCContext
*c
= s
->priv_data
;
192 ByteIOContext
*pb
= s
->pb
;
197 c
->header_pos
= url_ftell(pb
);
198 if(get_le32(pb
) != TAG_MPCK
){
199 av_log(s
, AV_LOG_ERROR
, "Not a Musepack8 file\n");
203 while(!url_feof(pb
)){
205 mpc8_get_chunk_header(pb
, &tag
, &size
);
206 if(tag
== TAG_STREAMHDR
)
208 mpc8_handle_chunk(s
, tag
, pos
, size
);
210 if(tag
!= TAG_STREAMHDR
){
211 av_log(s
, AV_LOG_ERROR
, "Stream header not found\n");
215 url_fskip(pb
, 4); //CRC
216 c
->ver
= get_byte(pb
);
218 av_log(s
, AV_LOG_ERROR
, "Unknown stream version %d\n", c
->ver
);
221 c
->samples
= ff_get_v(pb
);
222 ff_get_v(pb
); //silence samples at the beginning
224 st
= av_new_stream(s
, 0);
226 return AVERROR(ENOMEM
);
227 st
->codec
->codec_type
= CODEC_TYPE_AUDIO
;
228 st
->codec
->codec_id
= CODEC_ID_MUSEPACK8
;
229 st
->codec
->bits_per_coded_sample
= 16;
231 st
->codec
->extradata_size
= 2;
232 st
->codec
->extradata
= av_mallocz(st
->codec
->extradata_size
+ FF_INPUT_BUFFER_PADDING_SIZE
);
233 get_buffer(pb
, st
->codec
->extradata
, st
->codec
->extradata_size
);
235 st
->codec
->channels
= (st
->codec
->extradata
[1] >> 4) + 1;
236 st
->codec
->sample_rate
= mpc8_rate
[st
->codec
->extradata
[0] >> 5];
237 av_set_pts_info(st
, 32, 1152 << (st
->codec
->extradata
[1]&3)*2, st
->codec
->sample_rate
);
238 st
->duration
= c
->samples
/ (1152 << (st
->codec
->extradata
[1]&3)*2);
239 size
-= url_ftell(pb
) - pos
;
244 static int mpc8_read_packet(AVFormatContext
*s
, AVPacket
*pkt
)
246 MPCContext
*c
= s
->priv_data
;
250 while(!url_feof(s
->pb
)){
251 pos
= url_ftell(s
->pb
);
252 mpc8_get_chunk_header(s
->pb
, &tag
, &size
);
255 if(tag
== TAG_AUDIOPACKET
){
256 if(av_get_packet(s
->pb
, pkt
, size
) < 0)
257 return AVERROR(ENOMEM
);
258 pkt
->stream_index
= 0;
262 if(tag
== TAG_STREAMEND
)
264 mpc8_handle_chunk(s
, tag
, pos
, size
);
269 static int mpc8_read_seek(AVFormatContext
*s
, int stream_index
, int64_t timestamp
, int flags
)
271 AVStream
*st
= s
->streams
[stream_index
];
272 MPCContext
*c
= s
->priv_data
;
273 int index
= av_index_search_timestamp(st
, timestamp
, flags
);
275 if(index
< 0) return -1;
276 url_fseek(s
->pb
, st
->index_entries
[index
].pos
, SEEK_SET
);
277 c
->frame
= st
->index_entries
[index
].timestamp
;
282 AVInputFormat mpc8_demuxer
= {
284 NULL_IF_CONFIG_SMALL("Musepack SV8"),