| /* |
| * 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 |
| */ |
| |
| #include "libavutil/channel_layout.h" |
| #include "libavutil/intreadwrite.h" |
| #include "avformat.h" |
| #include "pcm.h" |
| |
| #define AT1_SU_SIZE 212 |
| |
| static int aea_read_probe(const 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 ch, i; |
| ch = p->buf[264]; |
| |
| if (ch != 1 && ch != 2) |
| return 0; |
| |
| /* 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 |
| */ |
| for (i = 2048; i + 211 < p->buf_size; i+= 212) { |
| int bsm_s, bsm_e, inb_s, inb_e; |
| bsm_s = p->buf[0]; |
| inb_s = p->buf[1]; |
| inb_e = p->buf[210]; |
| bsm_e = p->buf[211]; |
| |
| if (bsm_s != bsm_e || inb_s != inb_e) |
| return 0; |
| } |
| return AVPROBE_SCORE_MAX / 4 + 1; |
| } |
| return 0; |
| } |
| |
| static int aea_read_header(AVFormatContext *s) |
| { |
| AVStream *st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| |
| /* Parse the amount of channels and skip to pos 2048(0x800) */ |
| avio_skip(s->pb, 264); |
| st->codecpar->channels = avio_r8(s->pb); |
| avio_skip(s->pb, 1783); |
| |
| |
| st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; |
| st->codecpar->codec_id = AV_CODEC_ID_ATRAC1; |
| st->codecpar->sample_rate = 44100; |
| st->codecpar->bit_rate = 292000; |
| |
| if (st->codecpar->channels != 1 && st->codecpar->channels != 2) { |
| av_log(s, AV_LOG_ERROR, "Channels %d not supported!\n", st->codecpar->channels); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| st->codecpar->channel_layout = (st->codecpar->channels == 1) ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO; |
| |
| st->codecpar->block_align = AT1_SU_SIZE * st->codecpar->channels; |
| return 0; |
| } |
| |
| static int aea_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| int ret = av_get_packet(s->pb, pkt, s->streams[0]->codecpar->block_align); |
| |
| pkt->stream_index = 0; |
| if (ret <= 0) |
| return AVERROR(EIO); |
| |
| return ret; |
| } |
| |
| AVInputFormat ff_aea_demuxer = { |
| .name = "aea", |
| .long_name = NULL_IF_CONFIG_SMALL("MD STUDIO audio"), |
| .read_probe = aea_read_probe, |
| .read_header = aea_read_header, |
| .read_packet = aea_read_packet, |
| .read_seek = ff_pcm_read_seek, |
| .flags = AVFMT_GENERIC_INDEX, |
| .extensions = "aea", |
| }; |