libavformat/ads.c

   1 /*
   2  * ADS/SS2 demuxer
   3  * Copyright (c) 2015 Paul B Mahol
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg 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.
  11  *
  12  * FFmpeg 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.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "libavutil/channel_layout.h"
  23 #include "avformat.h"
  24 #include "demux.h"
  25 #include "internal.h"
  26
  27 static int ads_probe(const AVProbeData *p)
  28 {
  29     if (memcmp(p->buf, "SShd", 4) ||
  30         memcmp(p->buf+32, "SSbd", 4))
  31         return 0;
  32
  33     return AVPROBE_SCORE_MAX / 3 * 2;
  34 }
  35
  36 static int ads_read_header(AVFormatContext *s)
  37 {
  38     int align, codec;
  39     AVStream *st;
  40     int64_t size;
  41
  42     st = avformat_new_stream(s, NULL);
  43     if (!st)
  44         return AVERROR(ENOMEM);
  45
  46     avio_skip(s->pb, 8);
  47     st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
  48     codec                  = avio_rl32(s->pb);
  49     st->codecpar->sample_rate = avio_rl32(s->pb);
  50     if (st->codecpar->sample_rate <= 0)
  51         return AVERROR_INVALIDDATA;
  52     st->codecpar->ch_layout.nb_channels = avio_rl32(s->pb);
  53     if (st->codecpar->ch_layout.nb_channels <= 0)
  54         return AVERROR_INVALIDDATA;
  55     align                  = avio_rl32(s->pb);
  56     if (align <= 0 || align > INT_MAX / st->codecpar->ch_layout.nb_channels)
  57         return AVERROR_INVALIDDATA;
  58
  59     if (codec == 1)
  60         st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE_PLANAR;
  61     else
  62         st->codecpar->codec_id = AV_CODEC_ID_ADPCM_PSX;
  63
  64     st->codecpar->block_align = st->codecpar->ch_layout.nb_channels * align;
  65     avio_skip(s->pb, 12);
  66     size = avio_rl32(s->pb);
  67     if (st->codecpar->codec_id == AV_CODEC_ID_ADPCM_PSX && size >= 0x40)
  68         st->duration = (size - 0x40) / 16 / st->codecpar->ch_layout.nb_channels * 28;
  69     avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
  70
  71     return 0;
  72 }
  73
  74 static int ads_read_packet(AVFormatContext *s, AVPacket *pkt)
  75 {
  76     AVCodecParameters *par = s->streams[0]->codecpar;
  77     int ret;
  78
  79     ret = av_get_packet(s->pb, pkt, par->block_align);
  80     pkt->stream_index = 0;
  81     return ret;
  82 }
  83
  84 const FFInputFormat ff_ads_demuxer = {
  85     .p.name         = "ads",
  86     .p.long_name    = NULL_IF_CONFIG_SMALL("Sony PS2 ADS"),
  87     .p.extensions   = "ads,ss2",
  88     .read_probe     = ads_probe,
  89     .read_header    = ads_read_header,
  90     .read_packet    = ads_read_packet,
  91 };