libavformat/wady.c

   1 /*
   2  * WADY demuxer
   3  * Copyright (c) 2023 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 "libavutil/intreadwrite.h"
  24 #include "avformat.h"
  25 #include "demux.h"
  26 #include "internal.h"
  27 #include "pcm.h"
  28
  29 static int wady_probe(const AVProbeData *p)
  30 {
  31     if (AV_RL32(p->buf) != MKTAG('W','A','D','Y'))
  32         return 0;
  33     if (p->buf[4] != 0 || p->buf[5] == 0 ||
  34         AV_RL16(p->buf+6) == 0 ||
  35         AV_RL16(p->buf+6) > 2 ||
  36         (int32_t)AV_RL32(p->buf+8) <= 0)
  37         return 0;
  38
  39     return AVPROBE_SCORE_MAX / 3 * 2;
  40 }
  41
  42 static int wady_read_header(AVFormatContext *s)
  43 {
  44     AVIOContext *pb = s->pb;
  45     AVCodecParameters *par;
  46     int channels, ret;
  47     AVStream *st;
  48
  49     avio_skip(pb, 4 + 1);
  50
  51     st = avformat_new_stream(s, NULL);
  52     if (!st)
  53         return AVERROR(ENOMEM);
  54
  55     par              = st->codecpar;
  56     par->codec_type  = AVMEDIA_TYPE_AUDIO;
  57     par->codec_id    = AV_CODEC_ID_WADY_DPCM;
  58     par->format      = AV_SAMPLE_FMT_S16;
  59     if ((ret = ff_get_extradata(s, par, pb, 1)) < 0)
  60         return ret;
  61     channels         = avio_rl16(pb);
  62     if (channels == 0)
  63         return AVERROR_INVALIDDATA;
  64     av_channel_layout_default(&par->ch_layout, channels);
  65     par->sample_rate = avio_rl32(pb);
  66     if (par->sample_rate <= 0)
  67         return AVERROR_INVALIDDATA;
  68     avio_skip(pb, 4);
  69     st->duration = avio_rl32(pb);
  70     par->block_align = channels;
  71     avpriv_set_pts_info(st, 64, 1, par->sample_rate);
  72
  73     avio_seek(pb, 0x30, SEEK_SET);
  74
  75     return 0;
  76 }
  77
  78 const FFInputFormat ff_wady_demuxer = {
  79     .p.name         = "wady",
  80     .p.long_name    = NULL_IF_CONFIG_SMALL("Marble WADY"),
  81     .p.flags        = AVFMT_GENERIC_INDEX,
  82     .p.extensions   = "way",
  83     .read_probe     = wady_probe,
  84     .read_header    = wady_read_header,
  85     .read_packet    = ff_pcm_read_packet,
  86     .read_seek      = ff_pcm_read_seek,
  87 };