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| -rw-r--r-- | libavformat/aea.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/libavformat/aea.c b/libavformat/aea.c new file mode 100644 index 0000000000..f0e200d3fe --- /dev/null +++ b/libavformat/aea.c @@ -0,0 +1,110 @@ +/* + * MD STUDIO audio demuxer + * + * Copyright (c) 2009 Benjamin Larsson + * + * 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 + */ + +/** + * @file libavformat/aea.c + */ + +#include "avformat.h" +#include "raw.h" +#include "libavutil/intreadwrite.h" + +#define AT1_SU_SIZE 212 + +static int aea_read_probe(AVProbeData *p) +{ + if (p->buf_size <= 2048+212) + return 0; + + /* Magic is '00 08 00 00' in Little Endian*/ + if(AV_RL32(p->buf)==0x800) { + int bsm_s, bsm_e, inb_s, inb_e; + bsm_s = p->buf[2048]; + inb_s = p->buf[2048+1]; + inb_e = p->buf[2048+210]; + bsm_e = p->buf[2048+211]; + + + /* Check so that the redundant bsm bytes and info bytes are valid + * the block size mode bytes have to be the same + * the info bytes have to be the same + * the block size mode and info byte can't be the same + */ + if (bsm_s == bsm_e && inb_s == inb_e && bsm_s != inb_s) + return AVPROBE_SCORE_MAX/2; + } + return 0; +} + +static int aea_read_header(AVFormatContext *s, + AVFormatParameters *ap) +{ + AVStream *st = av_new_stream(s, 0); + if (!st) + return AVERROR(ENOMEM); + + /* Parse the amount of channels and skip to pos 2048(0x800) */ + url_fskip(s->pb, 264); + st->codec->channels = get_byte(s->pb); + url_fskip(s->pb, 1783); + + + st->codec->codec_type = CODEC_TYPE_AUDIO; + st->codec->codec_id = CODEC_ID_ATRAC1; + st->codec->sample_rate = 44100; + st->codec->bit_rate = 292000; + + if (st->codec->channels != 1 && st->codec->channels != 2) { + av_log(s,AV_LOG_ERROR,"Channels %d not supported!\n",st->codec->channels); + return -1; + } + + st->codec->channel_layout = (st->codec->channels==1) ? CH_LAYOUT_MONO : CH_LAYOUT_STEREO; + + st->codec->block_align = AT1_SU_SIZE * st->codec->channels; + return 0; +} + +static int aea_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + int ret = av_get_packet(s->pb, pkt, s->streams[0]->codec->block_align); + + pkt->stream_index = 0; + if (ret <= 0) + return AVERROR(EIO); + + return ret; +} + +AVInputFormat aea_demuxer = { + "aea", + NULL_IF_CONFIG_SMALL("MD STUDIO audio"), + 0, + aea_read_probe, + aea_read_header, + aea_read_packet, + 0, + pcm_read_seek, + .flags= AVFMT_GENERIC_INDEX, + .extensions = "aea", +}; + |