/* * 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(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",};