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[libav.git] / libavformat / mpc.c
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1/*
2 * Musepack demuxer
3 * Copyright (c) 2006 Konstantin Shishkov
4 *
2912e87a 5 * This file is part of Libav.
185c7b6b 6 *
2912e87a 7 * Libav is free software; you can redistribute it and/or
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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 *
2912e87a 12 * Libav is distributed in the hope that it will be useful,
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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
2912e87a 18 * License along with Libav; 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"
311f96a8 24#include "apetag.h"
3694ac24 25#include "id3v1.h"
d2d67e42 26#include "libavutil/dict.h"
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27
28#define MPC_FRAMESIZE 1152
aac88b53 29#define DELAY_FRAMES 32
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30
31static const int mpc_rate[4] = { 44100, 48000, 37800, 32000 };
32typedef struct {
33 int64_t pos;
34 int size, skip;
35}MPCFrame;
36
37typedef struct {
38 int ver;
39 uint32_t curframe, lastframe;
40 uint32_t fcount;
41 MPCFrame *frames;
42 int curbits;
43 int frames_noted;
44} MPCContext;
45
46static int mpc_probe(AVProbeData *p)
47{
48 const uint8_t *d = p->buf;
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49 if (d[0] == 'M' && d[1] == 'P' && d[2] == '+' && (d[3] == 0x17 || d[3] == 0x7))
50 return AVPROBE_SCORE_MAX;
51 return 0;
52}
53
54static int mpc_read_header(AVFormatContext *s, AVFormatParameters *ap)
55{
56 MPCContext *c = s->priv_data;
57 AVStream *st;
58
b7effd4e 59 if(avio_rl24(s->pb) != MKTAG('M', 'P', '+', 0)){
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60 av_log(s, AV_LOG_ERROR, "Not a Musepack file\n");
61 return -1;
185c7b6b 62 }
b7effd4e 63 c->ver = avio_r8(s->pb);
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64 if(c->ver != 0x07 && c->ver != 0x17){
65 av_log(s, AV_LOG_ERROR, "Can demux Musepack SV7, got version %02X\n", c->ver);
66 return -1;
67 }
b7effd4e 68 c->fcount = avio_rl32(s->pb);
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69 if((int64_t)c->fcount * sizeof(MPCFrame) >= UINT_MAX){
70 av_log(s, AV_LOG_ERROR, "Too many frames, seeking is not possible\n");
71 return -1;
72 }
73 c->frames = av_malloc(c->fcount * sizeof(MPCFrame));
74 c->curframe = 0;
75 c->lastframe = -1;
76 c->curbits = 8;
e3113632 77 c->frames_noted = 0;
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78
79 st = av_new_stream(s, 0);
80 if (!st)
769e10f0 81 return AVERROR(ENOMEM);
72415b2a 82 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
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83 st->codec->codec_id = CODEC_ID_MUSEPACK7;
84 st->codec->channels = 2;
dd1c8f3e 85 st->codec->bits_per_coded_sample = 16;
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86
87 st->codec->extradata_size = 16;
88 st->codec->extradata = av_mallocz(st->codec->extradata_size+FF_INPUT_BUFFER_PADDING_SIZE);
b7effd4e 89 avio_read(s->pb, st->codec->extradata, 16);
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90 st->codec->sample_rate = mpc_rate[st->codec->extradata[2] & 3];
91 av_set_pts_info(st, 32, MPC_FRAMESIZE, st->codec->sample_rate);
92 /* scan for seekpoints */
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93 st->start_time = 0;
94 st->duration = c->fcount;
185c7b6b 95
311f96a8 96 /* try to read APE tags */
8978feda 97 if (s->pb->seekable) {
a2704c97 98 int64_t pos = avio_tell(s->pb);
311f96a8 99 ff_ape_parse_tag(s);
d2d67e42 100 if (!av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX))
3694ac24 101 ff_id3v1_read(s);
6b4aa5da 102 avio_seek(s->pb, pos, SEEK_SET);
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103 }
104
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105 return 0;
106}
107
108static int mpc_read_packet(AVFormatContext *s, AVPacket *pkt)
109{
110 MPCContext *c = s->priv_data;
111 int ret, size, size2, curbits, cur = c->curframe;
112 int64_t tmp, pos;
113
d1886912 114 if (c->curframe >= c->fcount)
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115 return -1;
116
117 if(c->curframe != c->lastframe + 1){
6b4aa5da 118 avio_seek(s->pb, c->frames[c->curframe].pos, SEEK_SET);
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119 c->curbits = c->frames[c->curframe].skip;
120 }
121 c->lastframe = c->curframe;
122 c->curframe++;
123 curbits = c->curbits;
a2704c97 124 pos = avio_tell(s->pb);
b7effd4e 125 tmp = avio_rl32(s->pb);
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126 if(curbits <= 12){
127 size2 = (tmp >> (12 - curbits)) & 0xFFFFF;
128 }else{
b7effd4e 129 tmp = (tmp << 32) | avio_rl32(s->pb);
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130 size2 = (tmp >> (44 - curbits)) & 0xFFFFF;
131 }
132 curbits += 20;
6b4aa5da 133 avio_seek(s->pb, pos, SEEK_SET);
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134
135 size = ((size2 + curbits + 31) & ~31) >> 3;
136 if(cur == c->frames_noted){
137 c->frames[cur].pos = pos;
138 c->frames[cur].size = size;
139 c->frames[cur].skip = curbits - 20;
140 av_add_index_entry(s->streams[0], cur, cur, size, 0, AVINDEX_KEYFRAME);
141 c->frames_noted++;
142 }
143 c->curbits = (curbits + size2) & 0x1F;
144
145 if (av_new_packet(pkt, size) < 0)
6f3e0b21 146 return AVERROR(EIO);
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147
148 pkt->data[0] = curbits;
149 pkt->data[1] = (c->curframe > c->fcount);
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150 pkt->data[2] = 0;
151 pkt->data[3] = 0;
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152
153 pkt->stream_index = 0;
aac88b53 154 pkt->pts = cur;
b7effd4e 155 ret = avio_read(s->pb, pkt->data + 4, size);
185c7b6b 156 if(c->curbits)
6b4aa5da 157 avio_seek(s->pb, -4, SEEK_CUR);
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158 if(ret < size){
159 av_free_packet(pkt);
6f3e0b21 160 return AVERROR(EIO);
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161 }
162 pkt->size = ret + 4;
163
164 return 0;
165}
166
167static int mpc_read_close(AVFormatContext *s)
168{
169 MPCContext *c = s->priv_data;
170
171 av_freep(&c->frames);
172 return 0;
173}
174
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175/**
176 * Seek to the given position
177 * If position is unknown but is within the limits of file
178 * then packets are skipped unless desired position is reached
179 *
180 * Also this function makes use of the fact that timestamp == frameno
181 */
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182static int mpc_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
183{
184 AVStream *st = s->streams[stream_index];
185 MPCContext *c = s->priv_data;
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186 AVPacket pkt1, *pkt = &pkt1;
187 int ret;
aac88b53 188 int index = av_index_search_timestamp(st, timestamp - DELAY_FRAMES, flags);
e3113632 189 uint32_t lastframe;
185c7b6b 190
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191 /* if found, seek there */
192 if (index >= 0){
193 c->curframe = st->index_entries[index].pos;
194 return 0;
195 }
196 /* if timestamp is out of bounds, return error */
197 if(timestamp < 0 || timestamp >= c->fcount)
198 return -1;
aac88b53 199 timestamp -= DELAY_FRAMES;
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200 /* seek to the furthest known position and read packets until
201 we reach desired position */
202 lastframe = c->curframe;
203 if(c->frames_noted) c->curframe = c->frames_noted - 1;
204 while(c->curframe < timestamp){
205 ret = av_read_frame(s, pkt);
206 if (ret < 0){
207 c->curframe = lastframe;
208 return -1;
209 }
210 av_free_packet(pkt);
211 }
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212 return 0;
213}
214
215
c6610a21 216AVInputFormat ff_mpc_demuxer = {
185c7b6b 217 "mpc",
bde15e74 218 NULL_IF_CONFIG_SMALL("Musepack"),
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219 sizeof(MPCContext),
220 mpc_probe,
221 mpc_read_header,
222 mpc_read_packet,
223 mpc_read_close,
224 mpc_read_seek,
225 .extensions = "mpc",
226};