3 * Copyright (c) 2007 Konstantin Shishkov
5 * This file is part of Libav.
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavcodec/bitstream.h"
23 #include "libavcodec/unary.h"
28 #include "avio_internal.h"
31 #define MKMPCTAG(a, b) (a | (b << 8))
33 #define TAG_MPCK MKTAG('M','P','C','K')
37 TAG_STREAMHDR = MKMPCTAG('S','H'),
38 TAG_STREAMEND = MKMPCTAG('S','E'),
40 TAG_AUDIOPACKET = MKMPCTAG('A','P'),
42 TAG_SEEKTBLOFF = MKMPCTAG('S','O'),
43 TAG_SEEKTABLE = MKMPCTAG('S','T'),
45 TAG_REPLAYGAIN = MKMPCTAG('R','G'),
46 TAG_ENCINFO = MKMPCTAG('E','I'),
49 static const int mpc8_rate[8] = { 44100, 48000, 37800, 32000, -1, -1, -1, -1 };
51 typedef struct MPCContext {
59 static inline int64_t bs_get_v(uint8_t **bs)
77 static int mpc8_probe(AVProbeData *p)
79 uint8_t *bs = p->buf + 4;
80 uint8_t *bs_end = bs + p->buf_size;
85 if (AV_RL32(p->buf) != TAG_MPCK)
87 while (bs < bs_end + 3) {
88 int header_found = (bs[0] == 'S' && bs[1] == 'H');
89 if (bs[0] < 'A' || bs[0] > 'Z' || bs[1] < 'A' || bs[1] > 'Z')
95 if (bs + size - 2 >= bs_end)
96 return AVPROBE_SCORE_EXTENSION - 1; // seems to be valid MPC but no header yet
98 if (size < 11 || size > 28)
100 if (!AV_RL32(bs)) //zero CRC is invalid
102 return AVPROBE_SCORE_MAX;
110 static inline int64_t gb_get_v(BitstreamContext *bc)
114 while (bitstream_read_bit(bc) && bits < 64 - 7) {
116 v |= bitstream_read(bc, 7);
120 v |= bitstream_read(bc, 7);
125 static void mpc8_get_chunk_header(AVIOContext *pb, int *tag, int64_t *size)
129 *tag = avio_rl16(pb);
130 *size = ffio_read_varlen(pb);
131 *size -= avio_tell(pb) - pos;
134 static void mpc8_parse_seektable(AVFormatContext *s, int64_t off)
136 MPCContext *c = s->priv_data;
138 int64_t size, pos, ppos[2];
143 if (s->nb_streams == 0) {
144 av_log(s, AV_LOG_ERROR, "No stream added before parsing seek table\n");
148 avio_seek(s->pb, off, SEEK_SET);
149 mpc8_get_chunk_header(s->pb, &tag, &size);
150 if(tag != TAG_SEEKTABLE){
151 av_log(s, AV_LOG_ERROR, "No seek table at given position\n");
154 if (size < 0 || size >= INT_MAX / 2) {
155 av_log(s, AV_LOG_ERROR, "Bad seek table size\n");
158 if(!(buf = av_malloc(size + AV_INPUT_BUFFER_PADDING_SIZE)))
160 avio_read(s->pb, buf, size);
161 bitstream_init8(&bc, buf, size);
162 size = gb_get_v(&bc);
163 if(size > UINT_MAX/4 || size > c->samples/1152){
164 av_log(s, AV_LOG_ERROR, "Seek table is too big\n");
167 seekd = bitstream_read(&bc, 4);
168 for(i = 0; i < 2; i++){
169 pos = gb_get_v(&bc) + c->header_pos;
171 av_add_index_entry(s->streams[0], pos, i, 0, 0, AVINDEX_KEYFRAME);
173 for(; i < size; i++){
174 t = get_unary(&bc, 1, 33) << 12;
175 t += bitstream_read(&bc, 12);
178 pos = (t >> 1) + ppos[0]*2 - ppos[1];
179 av_add_index_entry(s->streams[0], pos, i << seekd, 0, 0, AVINDEX_KEYFRAME);
186 static void mpc8_handle_chunk(AVFormatContext *s, int tag, int64_t chunk_pos, int64_t size)
188 AVIOContext *pb = s->pb;
193 pos = avio_tell(pb) + size;
194 off = ffio_read_varlen(pb);
195 mpc8_parse_seektable(s, chunk_pos + off);
196 avio_seek(pb, pos, SEEK_SET);
203 static int mpc8_read_header(AVFormatContext *s)
205 MPCContext *c = s->priv_data;
206 AVIOContext *pb = s->pb;
211 c->header_pos = avio_tell(pb);
212 if(avio_rl32(pb) != TAG_MPCK){
213 av_log(s, AV_LOG_ERROR, "Not a Musepack8 file\n");
214 return AVERROR_INVALIDDATA;
217 while(!pb->eof_reached){
219 mpc8_get_chunk_header(pb, &tag, &size);
220 if(tag == TAG_STREAMHDR)
222 mpc8_handle_chunk(s, tag, pos, size);
224 if(tag != TAG_STREAMHDR){
225 av_log(s, AV_LOG_ERROR, "Stream header not found\n");
226 return AVERROR_INVALIDDATA;
229 avio_skip(pb, 4); //CRC
230 c->ver = avio_r8(pb);
232 avpriv_report_missing_feature(s, "Stream version %d", c->ver);
233 return AVERROR_PATCHWELCOME;
235 c->samples = ffio_read_varlen(pb);
236 ffio_read_varlen(pb); //silence samples at the beginning
238 st = avformat_new_stream(s, NULL);
240 return AVERROR(ENOMEM);
241 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
242 st->codecpar->codec_id = AV_CODEC_ID_MUSEPACK8;
243 st->codecpar->bits_per_coded_sample = 16;
245 st->codecpar->extradata_size = 2;
246 st->codecpar->extradata = av_mallocz(st->codecpar->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
247 avio_read(pb, st->codecpar->extradata, st->codecpar->extradata_size);
249 st->codecpar->channels = (st->codecpar->extradata[1] >> 4) + 1;
250 st->codecpar->sample_rate = mpc8_rate[st->codecpar->extradata[0] >> 5];
251 avpriv_set_pts_info(st, 32, 1152 << (st->codecpar->extradata[1]&3)*2, st->codecpar->sample_rate);
253 st->duration = c->samples / (1152 << (st->codecpar->extradata[1]&3)*2);
254 size -= avio_tell(pb) - pos;
256 if (pb->seekable & AVIO_SEEKABLE_NORMAL) {
257 int64_t pos = avio_tell(s->pb);
258 c->apetag_start = ff_ape_parse_tag(s);
259 avio_seek(s->pb, pos, SEEK_SET);
265 static int mpc8_read_packet(AVFormatContext *s, AVPacket *pkt)
267 MPCContext *c = s->priv_data;
271 while(!s->pb->eof_reached){
272 pos = avio_tell(s->pb);
274 /* don't return bogus packets with the ape tag data */
275 if (c->apetag_start && pos >= c->apetag_start)
278 mpc8_get_chunk_header(s->pb, &tag, &size);
281 if(tag == TAG_AUDIOPACKET){
282 if(av_get_packet(s->pb, pkt, size) < 0)
283 return AVERROR(ENOMEM);
284 pkt->stream_index = 0;
288 if(tag == TAG_STREAMEND)
290 mpc8_handle_chunk(s, tag, pos, size);
295 static int mpc8_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
297 AVStream *st = s->streams[stream_index];
298 int index = av_index_search_timestamp(st, timestamp, flags);
300 if(index < 0) return -1;
301 if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
303 ff_update_cur_dts(s, st, st->index_entries[index].timestamp);
308 AVInputFormat ff_mpc8_demuxer = {
310 .long_name = NULL_IF_CONFIG_SMALL("Musepack SV8"),
311 .priv_data_size = sizeof(MPCContext),
312 .read_probe = mpc8_probe,
313 .read_header = mpc8_read_header,
314 .read_packet = mpc8_read_packet,
315 .read_seek = mpc8_read_seek,