File size: 10,206 Bytes
8ead80b |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 |
/*
* Musepack SV8 demuxer
* Copyright (c) 2007 Konstantin Shishkov
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavcodec/get_bits.h"
#include "libavcodec/unary.h"
#include "apetag.h"
#include "avformat.h"
#include "demux.h"
#include "internal.h"
#include "avio_internal.h"
/// Two-byte MPC tag
#define MKMPCTAG(a, b) ((a) | ((b) << 8))
#define TAG_MPCK MKTAG('M','P','C','K')
/// Reserved MPC tags
enum MPCPacketTags{
TAG_STREAMHDR = MKMPCTAG('S','H'),
TAG_STREAMEND = MKMPCTAG('S','E'),
TAG_AUDIOPACKET = MKMPCTAG('A','P'),
TAG_SEEKTBLOFF = MKMPCTAG('S','O'),
TAG_SEEKTABLE = MKMPCTAG('S','T'),
TAG_REPLAYGAIN = MKMPCTAG('R','G'),
TAG_ENCINFO = MKMPCTAG('E','I'),
};
static const int mpc8_rate[8] = { 44100, 48000, 37800, 32000, -1, -1, -1, -1 };
typedef struct MPCContext {
int ver;
int64_t header_pos;
int64_t samples;
int64_t apetag_start;
} MPCContext;
static inline int64_t bs_get_v(const uint8_t **bs)
{
uint64_t v = 0;
int br = 0;
int c;
do {
c = **bs; (*bs)++;
v <<= 7;
v |= c & 0x7F;
br++;
if (br > 10)
return -1;
} while (c & 0x80);
return v - br;
}
static int mpc8_probe(const AVProbeData *p)
{
const uint8_t *bs = p->buf + 4;
const uint8_t *bs_end = bs + p->buf_size;
int64_t size;
if (p->buf_size < 16)
return 0;
if (AV_RL32(p->buf) != TAG_MPCK)
return 0;
while (bs < bs_end + 3) {
int header_found = (bs[0] == 'S' && bs[1] == 'H');
if (bs[0] < 'A' || bs[0] > 'Z' || bs[1] < 'A' || bs[1] > 'Z')
return 0;
bs += 2;
size = bs_get_v(&bs);
if (size < 2)
return 0;
if (size >= bs_end - bs + 2)
return AVPROBE_SCORE_EXTENSION - 1; // seems to be valid MPC but no header yet
if (header_found) {
if (size < 11 || size > 28)
return 0;
if (!AV_RL32(bs)) //zero CRC is invalid
return 0;
return AVPROBE_SCORE_MAX;
} else {
bs += size - 2;
}
}
return 0;
}
static inline int64_t gb_get_v(GetBitContext *gb)
{
uint64_t v = 0;
int bits = 0;
while(get_bits1(gb) && bits < 64-7){
v <<= 7;
v |= get_bits(gb, 7);
bits += 7;
}
v <<= 7;
v |= get_bits(gb, 7);
return v;
}
static void mpc8_get_chunk_header(AVIOContext *pb, int *tag, int64_t *size)
{
int64_t pos;
pos = avio_tell(pb);
*tag = avio_rl16(pb);
*size = ffio_read_varlen(pb);
pos -= avio_tell(pb);
if (av_sat_add64(*size, pos) != (uint64_t)*size + pos) {
*size = -1;
} else
*size += pos;
}
static int mpc8_parse_seektable(AVFormatContext *s, int64_t off)
{
MPCContext *c = s->priv_data;
int tag;
int64_t size, pos, ppos[2];
uint8_t *buf;
int i, t, seekd, ret;
int64_t ret64;
GetBitContext gb;
if (s->nb_streams == 0) {
av_log(s, AV_LOG_ERROR, "No stream added before parsing seek table\n");
return AVERROR_INVALIDDATA;
}
ret64 = avio_seek(s->pb, off, SEEK_SET);
if (ret64 < 0)
return AVERROR_INVALIDDATA;
mpc8_get_chunk_header(s->pb, &tag, &size);
if(tag != TAG_SEEKTABLE || avio_feof(s->pb)){
av_log(s, AV_LOG_ERROR, "No seek table at given position\n");
return AVERROR_INVALIDDATA;
}
if (size > INT_MAX/10 || size<=0) {
av_log(s, AV_LOG_ERROR, "Bad seek table size\n");
return AVERROR_INVALIDDATA;
}
if(!(buf = av_malloc(size + AV_INPUT_BUFFER_PADDING_SIZE)))
return AVERROR(ENOMEM);
ret = avio_read(s->pb, buf, size);
if (ret != size) {
av_log(s, AV_LOG_ERROR, "seek table truncated\n");
av_free(buf);
return AVERROR_INVALIDDATA;
}
memset(buf+size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
init_get_bits(&gb, buf, size * 8);
size = gb_get_v(&gb);
if(size > UINT_MAX/4 || size > c->samples/1152){
av_log(s, AV_LOG_ERROR, "Seek table is too big\n");
av_free(buf);
return AVERROR_INVALIDDATA;
}
seekd = get_bits(&gb, 4);
for(i = 0; i < 2; i++){
pos = gb_get_v(&gb);
if (av_sat_add64(pos, c->header_pos) != pos + (uint64_t)c->header_pos) {
av_free(buf);
return AVERROR_INVALIDDATA;
}
pos += c->header_pos;
ppos[1 - i] = pos;
av_add_index_entry(s->streams[0], pos, i, 0, 0, AVINDEX_KEYFRAME);
}
for(; i < size; i++){
if (get_bits_left(&gb) < 13) {
av_free(buf);
return AVERROR_INVALIDDATA;
}
t = get_unary(&gb, 1, 33) << 12;
t += get_bits(&gb, 12);
if(t & 1)
t = -(t & ~1);
pos = (t >> 1) + (uint64_t)ppos[0]*2 - ppos[1];
av_add_index_entry(s->streams[0], pos, (int64_t)i << seekd, 0, 0, AVINDEX_KEYFRAME);
ppos[1] = ppos[0];
ppos[0] = pos;
}
av_free(buf);
return 0;
}
static int mpc8_handle_chunk(AVFormatContext *s, int tag, int64_t chunk_pos, int64_t size)
{
AVIOContext *pb = s->pb;
int64_t pos, off;
int ret;
switch(tag){
case TAG_SEEKTBLOFF:
pos = avio_tell(pb);
off = ffio_read_varlen(pb);
if (pos > INT64_MAX - size || off < 0 || off > INT64_MAX - chunk_pos)
return AVERROR_INVALIDDATA;
pos += size;
ret = mpc8_parse_seektable(s, chunk_pos + off);
if (ret < 0)
return AVERROR_INVALIDDATA;
avio_seek(pb, pos, SEEK_SET);
break;
default:
avio_skip(pb, size);
}
return 0;
}
static int mpc8_read_header(AVFormatContext *s)
{
MPCContext *c = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *st;
int tag = 0, ret;
int channels;
int64_t size, pos;
c->header_pos = avio_tell(pb);
if(avio_rl32(pb) != TAG_MPCK){
av_log(s, AV_LOG_ERROR, "Not a Musepack8 file\n");
return AVERROR_INVALIDDATA;
}
while(!avio_feof(pb)){
pos = avio_tell(pb);
mpc8_get_chunk_header(pb, &tag, &size);
if (size < 0) {
av_log(s, AV_LOG_ERROR, "Invalid chunk length\n");
return AVERROR_INVALIDDATA;
}
if(tag == TAG_STREAMHDR)
break;
ret = mpc8_handle_chunk(s, tag, pos, size);
if (ret < 0)
return ret;
}
if(tag != TAG_STREAMHDR){
av_log(s, AV_LOG_ERROR, "Stream header not found\n");
return AVERROR_INVALIDDATA;
}
pos = avio_tell(pb);
avio_skip(pb, 4); //CRC
c->ver = avio_r8(pb);
if(c->ver != 8){
avpriv_report_missing_feature(s, "Stream version %d", c->ver);
return AVERROR_PATCHWELCOME;
}
c->samples = ffio_read_varlen(pb);
ffio_read_varlen(pb); //silence samples at the beginning
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->codec_id = AV_CODEC_ID_MUSEPACK8;
st->codecpar->bits_per_coded_sample = 16;
if ((ret = ff_get_extradata(s, st->codecpar, pb, 2)) < 0)
return ret;
channels = (st->codecpar->extradata[1] >> 4) + 1;
st->codecpar->ch_layout.nb_channels = channels;
st->codecpar->sample_rate = mpc8_rate[st->codecpar->extradata[0] >> 5];
avpriv_set_pts_info(st, 64, 1152 << (st->codecpar->extradata[1]&3)*2, st->codecpar->sample_rate);
st->start_time = 0;
st->duration = c->samples / (1152 << (st->codecpar->extradata[1]&3)*2);
size -= avio_tell(pb) - pos;
if (size > 0)
avio_skip(pb, size);
if (pb->seekable & AVIO_SEEKABLE_NORMAL) {
int64_t pos = avio_tell(s->pb);
c->apetag_start = ff_ape_parse_tag(s);
avio_seek(s->pb, pos, SEEK_SET);
}
return 0;
}
static int mpc8_read_packet(AVFormatContext *s, AVPacket *pkt)
{
MPCContext *c = s->priv_data;
int tag, ret;
int64_t pos, size;
while(!avio_feof(s->pb)){
pos = avio_tell(s->pb);
/* don't return bogus packets with the ape tag data */
if (c->apetag_start && pos >= c->apetag_start)
return AVERROR_EOF;
mpc8_get_chunk_header(s->pb, &tag, &size);
if (size < 0 || size > INT_MAX)
return -1;
if(tag == TAG_AUDIOPACKET){
if ((ret = av_get_packet(s->pb, pkt, size)) < 0)
return ret;
pkt->stream_index = 0;
pkt->duration = 1;
return 0;
}
if(tag == TAG_STREAMEND)
return AVERROR_EOF;
mpc8_handle_chunk(s, tag, pos, size);
}
return AVERROR_EOF;
}
static int mpc8_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
{
AVStream *st = s->streams[stream_index];
FFStream *const sti = ffstream(st);
int index = av_index_search_timestamp(st, timestamp, flags);
if(index < 0) return -1;
if (avio_seek(s->pb, sti->index_entries[index].pos, SEEK_SET) < 0)
return -1;
avpriv_update_cur_dts(s, st, sti->index_entries[index].timestamp);
return 0;
}
const AVInputFormat ff_mpc8_demuxer = {
.name = "mpc8",
.long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
.priv_data_size = sizeof(MPCContext),
.read_probe = mpc8_probe,
.read_header = mpc8_read_header,
.read_packet = mpc8_read_packet,
.read_seek = mpc8_read_seek,
};
|