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* Copyright (c) 2007 Konstantin Shishkov
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* This file is part of FFmpeg.
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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#include "bitstream.h"
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#define MKMPCTAG(a, b) (a | (b << 8))
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#define TAG_MPCK MKTAG('M','P','C','K')
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TAG_STREAMHDR = MKMPCTAG('S','H'),
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TAG_STREAMEND = MKMPCTAG('S','E'),
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TAG_AUDIOPACKET = MKMPCTAG('A','P'),
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TAG_SEEKTBLOFF = MKMPCTAG('S','O'),
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TAG_SEEKTABLE = MKMPCTAG('S','T'),
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TAG_REPLAYGAIN = MKMPCTAG('R','G'),
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TAG_ENCINFO = MKMPCTAG('E','I'),
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static const int mpc8_rate[8] = { 44100, 48000, 37800, 32000, -1, -1, -1, -1 };
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static int mpc8_probe(AVProbeData *p)
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if (AV_RL32(p->buf) == TAG_MPCK)
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return AVPROBE_SCORE_MAX;
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static inline int64_t gb_get_v(GetBitContext *gb)
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while(get_bits1(gb) && bits < 64-7){
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static void mpc8_get_chunk_header(ByteIOContext *pb, int *tag, int64_t *size)
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*size -= url_ftell(pb) - pos;
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static void mpc8_parse_seektable(AVFormatContext *s, int64_t off)
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MPCContext *c = s->priv_data;
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int64_t size, pos, ppos[2];
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url_fseek(s->pb, off, SEEK_SET);
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mpc8_get_chunk_header(s->pb, &tag, &size);
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if(tag != TAG_SEEKTABLE){
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av_log(s, AV_LOG_ERROR, "No seek table at given position\n");
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if(!(buf = av_malloc(size)))
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get_buffer(s->pb, buf, size);
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init_get_bits(&gb, buf, size * 8);
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size = gb_get_v(&gb);
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if(size > UINT_MAX/4 || size > c->samples/1152){
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av_log(s, AV_LOG_ERROR, "Seek table is too big\n");
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seekd = get_bits(&gb, 4);
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for(i = 0; i < 2; i++){
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pos = gb_get_v(&gb) + c->header_pos;
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av_add_index_entry(s->streams[0], pos, i, 0, 0, AVINDEX_KEYFRAME);
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for(; i < size; i++){
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t = get_unary(&gb, 1, 33) << 12;
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t += get_bits(&gb, 12);
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pos = (t >> 1) + ppos[0]*2 - ppos[1];
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av_add_index_entry(s->streams[0], pos, i << seekd, 0, 0, AVINDEX_KEYFRAME);
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static void mpc8_handle_chunk(AVFormatContext *s, int tag, int64_t chunk_pos, int64_t size)
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ByteIOContext *pb = s->pb;
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pos = url_ftell(pb) + size;
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mpc8_parse_seektable(s, chunk_pos + off);
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url_fseek(pb, pos, SEEK_SET);
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static int mpc8_read_header(AVFormatContext *s, AVFormatParameters *ap)
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MPCContext *c = s->priv_data;
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ByteIOContext *pb = s->pb;
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c->header_pos = url_ftell(pb);
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if(get_le32(pb) != TAG_MPCK){
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av_log(s, AV_LOG_ERROR, "Not a Musepack8 file\n");
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while(!url_feof(pb)){
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mpc8_get_chunk_header(pb, &tag, &size);
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if(tag == TAG_STREAMHDR)
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mpc8_handle_chunk(s, tag, pos, size);
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if(tag != TAG_STREAMHDR){
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av_log(s, AV_LOG_ERROR, "Stream header not found\n");
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url_fskip(pb, 4); //CRC
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c->ver = get_byte(pb);
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av_log(s, AV_LOG_ERROR, "Unknown stream version %d\n", c->ver);
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c->samples = ff_get_v(pb);
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ff_get_v(pb); //silence samples at the beginning
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st = av_new_stream(s, 0);
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return AVERROR(ENOMEM);
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st->codec->codec_type = CODEC_TYPE_AUDIO;
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st->codec->codec_id = CODEC_ID_MUSEPACK8;
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st->codec->bits_per_sample = 16;
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st->codec->extradata_size = 2;
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st->codec->extradata = av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
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get_buffer(pb, st->codec->extradata, st->codec->extradata_size);
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st->codec->channels = (st->codec->extradata[1] >> 4) + 1;
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st->codec->sample_rate = mpc8_rate[st->codec->extradata[0] >> 5];
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av_set_pts_info(st, 32, 1152 << (st->codec->extradata[1]&3)*2, st->codec->sample_rate);
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st->duration = c->samples / (1152 << (st->codec->extradata[1]&3)*2);
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size -= url_ftell(pb) - pos;
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static int mpc8_read_packet(AVFormatContext *s, AVPacket *pkt)
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MPCContext *c = s->priv_data;
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while(!url_feof(s->pb)){
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pos = url_ftell(s->pb);
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mpc8_get_chunk_header(s->pb, &tag, &size);
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if(tag == TAG_AUDIOPACKET){
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if(av_get_packet(s->pb, pkt, size) < 0)
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return AVERROR(ENOMEM);
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pkt->stream_index = 0;
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if(tag == TAG_STREAMEND)
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mpc8_handle_chunk(s, tag, pos, size);
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static int mpc8_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
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AVStream *st = s->streams[stream_index];
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MPCContext *c = s->priv_data;
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int index = av_index_search_timestamp(st, timestamp, flags);
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if(index < 0) return -1;
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url_fseek(s->pb, st->index_entries[index].pos, SEEK_SET);
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c->frame = st->index_entries[index].timestamp;
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AVInputFormat mpc8_demuxer = {