libavformat/ircamdec.c

   1 /*
   2  * IRCAM demuxer
   3  * Copyright (c) 2012 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/intfloat.h"
  23 #include "libavutil/intreadwrite.h"
  24 #include "libavcodec/internal.h"
  25 #include "avformat.h"
  26 #include "demux.h"
  27 #include "internal.h"
  28 #include "pcm.h"
  29 #include "ircam.h"
  30
  31 static int ircam_probe(const AVProbeData *p)
  32 {
  33     if ((p->buf[0] == 0x64 && p->buf[1] == 0xA3 && p->buf[3] == 0x00 &&
  34          p->buf[2] >=    1 && p->buf[2] <= 4) ||
  35         (p->buf[3] == 0x64 && p->buf[2] == 0xA3 && p->buf[0] == 0x00 &&
  36          p->buf[1] >=    1 && p->buf[1] <= 3) &&
  37         AV_RN32(p->buf + 4) && AV_RN32(p->buf + 8))
  38         return AVPROBE_SCORE_MAX / 4 * 3;
  39     return 0;
  40 }
  41
  42 static const struct endianness {
  43     uint32_t magic;
  44     int      is_le;
  45 } table[] = {
  46   { 0x64A30100, 0 },
  47   { 0x64A30200, 1 },
  48   { 0x64A30300, 0 },
  49   { 0x64A30400, 1 },
  50   { 0x0001A364, 1 },
  51   { 0x0002A364, 0 },
  52   { 0x0003A364, 1 },
  53 };
  54
  55 static int ircam_read_header(AVFormatContext *s)
  56 {
  57     uint32_t magic, sample_rate, channels, tag;
  58     const AVCodecTag *tags;
  59     int le = -1, i;
  60     AVStream *st;
  61
  62     magic = avio_rl32(s->pb);
  63     for (i = 0; i < 7; i++) {
  64         if (magic == table[i].magic) {
  65             le = table[i].is_le;
  66             break;
  67         }
  68     }
  69
  70     if (le == 1) {
  71         sample_rate = lrintf(av_int2float(avio_rl32(s->pb)));
  72         channels    = avio_rl32(s->pb);
  73         tag         = avio_rl32(s->pb);
  74         tags        = ff_codec_ircam_le_tags;
  75     } else if (le == 0) {
  76         sample_rate = lrintf(av_int2float(avio_rb32(s->pb)));
  77         channels    = avio_rb32(s->pb);
  78         tag         = avio_rb32(s->pb);
  79         tags        = ff_codec_ircam_be_tags;
  80     } else {
  81         return AVERROR_INVALIDDATA;
  82     }
  83
  84     if (!channels || !sample_rate)
  85         return AVERROR_INVALIDDATA;
  86
  87     st = avformat_new_stream(s, NULL);
  88     if (!st)
  89         return AVERROR(ENOMEM);
  90
  91     st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
  92     st->codecpar->ch_layout.nb_channels = channels;
  93     if (st->codecpar->ch_layout.nb_channels > FF_SANE_NB_CHANNELS)
  94         return AVERROR(ENOSYS);
  95     st->codecpar->sample_rate = sample_rate;
  96
  97     st->codecpar->codec_id = ff_codec_get_id(tags, tag);
  98     if (st->codecpar->codec_id == AV_CODEC_ID_NONE) {
  99         av_log(s, AV_LOG_ERROR, "unknown tag %"PRIx32"\n", tag);
 100         return AVERROR_INVALIDDATA;
 101     }
 102
 103     st->codecpar->bits_per_coded_sample = av_get_bits_per_sample(st->codecpar->codec_id);
 104     st->codecpar->block_align = st->codecpar->bits_per_coded_sample *
 105                                 st->codecpar->ch_layout.nb_channels / 8;
 106     avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
 107     avio_skip(s->pb, 1008);
 108
 109     return 0;
 110 }
 111
 112 const FFInputFormat ff_ircam_demuxer = {
 113     .p.name         = "ircam",
 114     .p.long_name    = NULL_IF_CONFIG_SMALL("Berkeley/IRCAM/CARL Sound Format"),
 115     .p.extensions   = "sf,ircam",
 116     .p.flags        = AVFMT_GENERIC_INDEX,
 117     .read_probe     = ircam_probe,
 118     .read_header    = ircam_read_header,
 119     .read_packet    = ff_pcm_read_packet,
 120     .read_seek      = ff_pcm_read_seek,
 121 };