Parse ID3 tags in Musepack SV7 files
[libav.git] / libavformat / mpc.c
CommitLineData
185c7b6b
KS
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
e5a389a1 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
185c7b6b 20 */
245976da 21
9106a698 22#include "libavcodec/get_bits.h"
185c7b6b 23#include "avformat.h"
ac3ef4a4 24#include "id3v2.h"
311f96a8 25#include "apetag.h"
185c7b6b
KS
26
27#define MPC_FRAMESIZE 1152
aac88b53 28#define DELAY_FRAMES 32
185c7b6b
KS
29
30static const int mpc_rate[4] = { 44100, 48000, 37800, 32000 };
31typedef struct {
32 int64_t pos;
33 int size, skip;
34}MPCFrame;
35
36typedef struct {
37 int ver;
38 uint32_t curframe, lastframe;
39 uint32_t fcount;
40 MPCFrame *frames;
41 int curbits;
42 int frames_noted;
43} MPCContext;
44
45static int mpc_probe(AVProbeData *p)
46{
47 const uint8_t *d = p->buf;
ac3ef4a4
AC
48 if (ff_id3v2_match(d)) {
49 d += ff_id3v2_tag_len(d);
50 }
51 if (d+3 < p->buf+p->buf_size)
185c7b6b
KS
52 if (d[0] == 'M' && d[1] == 'P' && d[2] == '+' && (d[3] == 0x17 || d[3] == 0x7))
53 return AVPROBE_SCORE_MAX;
54 return 0;
55}
56
57static int mpc_read_header(AVFormatContext *s, AVFormatParameters *ap)
58{
59 MPCContext *c = s->priv_data;
60 AVStream *st;
5f71844e
MH
61 int t, ret;
62 int64_t pos = url_ftell(s->pb);
185c7b6b 63
899681cd 64 t = get_le24(s->pb);
0587b0ca 65 if(t != MKTAG('M', 'P', '+', 0)){
5f71844e
MH
66 uint8_t buf[ID3v2_HEADER_SIZE];
67 if (url_fseek(s->pb, pos, SEEK_SET) < 0)
68 return -1;
69 ret = get_buffer(s->pb, buf, ID3v2_HEADER_SIZE);
70 if (ret != ID3v2_HEADER_SIZE || !ff_id3v2_match(buf)) {
0587b0ca
KS
71 av_log(s, AV_LOG_ERROR, "Not a Musepack file\n");
72 return -1;
73 }
74 /* skip ID3 tags and try again */
5f71844e 75 t = ff_id3v2_tag_len(buf) - ID3v2_HEADER_SIZE;
0587b0ca 76 av_log(s, AV_LOG_DEBUG, "Skipping %d(%X) bytes of ID3 data\n", t, t);
899681cd
BA
77 url_fskip(s->pb, t);
78 if(get_le24(s->pb) != MKTAG('M', 'P', '+', 0)){
0587b0ca
KS
79 av_log(s, AV_LOG_ERROR, "Not a Musepack file\n");
80 return -1;
81 }
5f71844e
MH
82 /* read ID3 tags */
83 if (url_fseek(s->pb, pos, SEEK_SET) < 0)
84 return -1;
85 ff_id3v2_read(s);
86 get_le24(s->pb);
185c7b6b 87 }
899681cd 88 c->ver = get_byte(s->pb);
185c7b6b
KS
89 if(c->ver != 0x07 && c->ver != 0x17){
90 av_log(s, AV_LOG_ERROR, "Can demux Musepack SV7, got version %02X\n", c->ver);
91 return -1;
92 }
899681cd 93 c->fcount = get_le32(s->pb);
185c7b6b
KS
94 if((int64_t)c->fcount * sizeof(MPCFrame) >= UINT_MAX){
95 av_log(s, AV_LOG_ERROR, "Too many frames, seeking is not possible\n");
96 return -1;
97 }
98 c->frames = av_malloc(c->fcount * sizeof(MPCFrame));
99 c->curframe = 0;
100 c->lastframe = -1;
101 c->curbits = 8;
e3113632 102 c->frames_noted = 0;
185c7b6b
KS
103
104 st = av_new_stream(s, 0);
105 if (!st)
769e10f0 106 return AVERROR(ENOMEM);
185c7b6b
KS
107 st->codec->codec_type = CODEC_TYPE_AUDIO;
108 st->codec->codec_id = CODEC_ID_MUSEPACK7;
109 st->codec->channels = 2;
dd1c8f3e 110 st->codec->bits_per_coded_sample = 16;
185c7b6b
KS
111
112 st->codec->extradata_size = 16;
113 st->codec->extradata = av_mallocz(st->codec->extradata_size+FF_INPUT_BUFFER_PADDING_SIZE);
899681cd 114 get_buffer(s->pb, st->codec->extradata, 16);
185c7b6b
KS
115 st->codec->sample_rate = mpc_rate[st->codec->extradata[2] & 3];
116 av_set_pts_info(st, 32, MPC_FRAMESIZE, st->codec->sample_rate);
117 /* scan for seekpoints */
118 s->start_time = 0;
119 s->duration = (int64_t)c->fcount * MPC_FRAMESIZE * AV_TIME_BASE / st->codec->sample_rate;
120
311f96a8
MH
121 /* try to read APE tags */
122 if (!url_is_streamed(s->pb)) {
123 int64_t pos = url_ftell(s->pb);
124 ff_ape_parse_tag(s);
125 url_fseek(s->pb, pos, SEEK_SET);
126 }
127
185c7b6b
KS
128 return 0;
129}
130
131static int mpc_read_packet(AVFormatContext *s, AVPacket *pkt)
132{
133 MPCContext *c = s->priv_data;
134 int ret, size, size2, curbits, cur = c->curframe;
135 int64_t tmp, pos;
136
d1886912 137 if (c->curframe >= c->fcount)
185c7b6b
KS
138 return -1;
139
140 if(c->curframe != c->lastframe + 1){
899681cd 141 url_fseek(s->pb, c->frames[c->curframe].pos, SEEK_SET);
185c7b6b
KS
142 c->curbits = c->frames[c->curframe].skip;
143 }
144 c->lastframe = c->curframe;
145 c->curframe++;
146 curbits = c->curbits;
899681cd
BA
147 pos = url_ftell(s->pb);
148 tmp = get_le32(s->pb);
185c7b6b
KS
149 if(curbits <= 12){
150 size2 = (tmp >> (12 - curbits)) & 0xFFFFF;
151 }else{
899681cd 152 tmp = (tmp << 32) | get_le32(s->pb);
185c7b6b
KS
153 size2 = (tmp >> (44 - curbits)) & 0xFFFFF;
154 }
155 curbits += 20;
899681cd 156 url_fseek(s->pb, pos, SEEK_SET);
185c7b6b
KS
157
158 size = ((size2 + curbits + 31) & ~31) >> 3;
159 if(cur == c->frames_noted){
160 c->frames[cur].pos = pos;
161 c->frames[cur].size = size;
162 c->frames[cur].skip = curbits - 20;
163 av_add_index_entry(s->streams[0], cur, cur, size, 0, AVINDEX_KEYFRAME);
164 c->frames_noted++;
165 }
166 c->curbits = (curbits + size2) & 0x1F;
167
168 if (av_new_packet(pkt, size) < 0)
6f3e0b21 169 return AVERROR(EIO);
185c7b6b
KS
170
171 pkt->data[0] = curbits;
172 pkt->data[1] = (c->curframe > c->fcount);
173
174 pkt->stream_index = 0;
aac88b53 175 pkt->pts = cur;
899681cd 176 ret = get_buffer(s->pb, pkt->data + 4, size);
185c7b6b 177 if(c->curbits)
899681cd 178 url_fseek(s->pb, -4, SEEK_CUR);
185c7b6b
KS
179 if(ret < size){
180 av_free_packet(pkt);
6f3e0b21 181 return AVERROR(EIO);
185c7b6b
KS
182 }
183 pkt->size = ret + 4;
184
185 return 0;
186}
187
188static int mpc_read_close(AVFormatContext *s)
189{
190 MPCContext *c = s->priv_data;
191
192 av_freep(&c->frames);
193 return 0;
194}
195
e3113632
KS
196/**
197 * Seek to the given position
198 * If position is unknown but is within the limits of file
199 * then packets are skipped unless desired position is reached
200 *
201 * Also this function makes use of the fact that timestamp == frameno
202 */
185c7b6b
KS
203static int mpc_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
204{
205 AVStream *st = s->streams[stream_index];
206 MPCContext *c = s->priv_data;
e3113632
KS
207 AVPacket pkt1, *pkt = &pkt1;
208 int ret;
aac88b53 209 int index = av_index_search_timestamp(st, timestamp - DELAY_FRAMES, flags);
e3113632 210 uint32_t lastframe;
185c7b6b 211
e3113632
KS
212 /* if found, seek there */
213 if (index >= 0){
214 c->curframe = st->index_entries[index].pos;
215 return 0;
216 }
217 /* if timestamp is out of bounds, return error */
218 if(timestamp < 0 || timestamp >= c->fcount)
219 return -1;
aac88b53 220 timestamp -= DELAY_FRAMES;
e3113632
KS
221 /* seek to the furthest known position and read packets until
222 we reach desired position */
223 lastframe = c->curframe;
224 if(c->frames_noted) c->curframe = c->frames_noted - 1;
225 while(c->curframe < timestamp){
226 ret = av_read_frame(s, pkt);
227 if (ret < 0){
228 c->curframe = lastframe;
229 return -1;
230 }
231 av_free_packet(pkt);
232 }
185c7b6b
KS
233 return 0;
234}
235
236
237AVInputFormat mpc_demuxer = {
238 "mpc",
bde15e74 239 NULL_IF_CONFIG_SMALL("Musepack"),
185c7b6b
KS
240 sizeof(MPCContext),
241 mpc_probe,
242 mpc_read_header,
243 mpc_read_packet,
244 mpc_read_close,
245 mpc_read_seek,
246 .extensions = "mpc",
247};