libavformat/wvedec.c

   1 /*
   2  * Copyright (c) 2015 Paul B Mahol
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include "avformat.h"
  22 #include "demux.h"
  23 #include "internal.h"
  24 #include "pcm.h"
  25
  26 static int wve_probe(const AVProbeData *p)
  27 {
  28     if (memcmp(p->buf, "ALawSoundFile**\0\017\020", 18) ||
  29         memcmp(p->buf + 22, "\0\0\0\1\0\0\0\0\0\0", 10))
  30         return 0;
  31     return AVPROBE_SCORE_MAX;
  32 }
  33
  34 static int wve_read_header(AVFormatContext *s)
  35 {
  36     AVStream *st;
  37
  38     st = avformat_new_stream(s, NULL);
  39     if (!st)
  40         return AVERROR(ENOMEM);
  41
  42     avio_skip(s->pb, 18);
  43     st->duration           = avio_rb32(s->pb);
  44     st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
  45     st->codecpar->codec_id    = AV_CODEC_ID_PCM_ALAW;
  46     st->codecpar->sample_rate = 8000;
  47     st->codecpar->ch_layout.nb_channels = 1;
  48     st->codecpar->bits_per_coded_sample = 8;
  49     st->codecpar->block_align = st->codecpar->bits_per_coded_sample *
  50                                 st->codecpar->ch_layout.nb_channels / 8;
  51     avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
  52     avio_skip(s->pb, 10);
  53
  54     return 0;
  55 }
  56
  57 const FFInputFormat ff_wve_demuxer = {
  58     .p.name         = "wve",
  59     .p.long_name    = NULL_IF_CONFIG_SMALL("Psion 3 audio"),
  60     .read_probe     = wve_probe,
  61     .read_header    = wve_read_header,
  62     .read_packet    = ff_pcm_read_packet,
  63     .read_seek      = ff_pcm_read_seek,
  64 };