libavformat/soxdec.c

   1 /*
   2  * SoX native format demuxer
   3  * Copyright (c) 2009 Daniel Verkamp <daniel@drv.nu>
   4  *
   5  * Based on libSoX sox-fmt.c
   6  * Copyright (c) 2008 robs@users.sourceforge.net
   7  *
   8  * This file is part of Libav.
   9  *
  10  * Libav is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * Libav is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public
  21  * License along with Libav; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  23  */
  24
  25 /**
  26  * @file
  27  * SoX native format demuxer
  28  * @author Daniel Verkamp
  29  * @see http://wiki.multimedia.cx/index.php?title=SoX_native_intermediate_format
  30  */
  31
  32 #include "libavutil/intreadwrite.h"
  33 #include "libavutil/intfloat.h"
  34 #include "libavutil/dict.h"
  35 #include "avformat.h"
  36 #include "internal.h"
  37 #include "pcm.h"
  38 #include "sox.h"
  39
  40 static int sox_probe(AVProbeData *p)
  41 {
  42     if (AV_RL32(p->buf) == SOX_TAG || AV_RB32(p->buf) == SOX_TAG)
  43         return AVPROBE_SCORE_MAX;
  44     return 0;
  45 }
  46
  47 static int sox_read_header(AVFormatContext *s)
  48 {
  49     AVIOContext *pb = s->pb;
  50     unsigned header_size, comment_size;
  51     double sample_rate, sample_rate_frac;
  52     AVStream *st;
  53
  54     st = avformat_new_stream(s, NULL);
  55     if (!st)
  56         return AVERROR(ENOMEM);
  57
  58     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
  59
  60     if (avio_rl32(pb) == SOX_TAG) {
  61         st->codec->codec_id = AV_CODEC_ID_PCM_S32LE;
  62         header_size         = avio_rl32(pb);
  63         avio_skip(pb, 8); /* sample count */
  64         sample_rate         = av_int2double(avio_rl64(pb));
  65         st->codec->channels = avio_rl32(pb);
  66         comment_size        = avio_rl32(pb);
  67     } else {
  68         st->codec->codec_id = AV_CODEC_ID_PCM_S32BE;
  69         header_size         = avio_rb32(pb);
  70         avio_skip(pb, 8); /* sample count */
  71         sample_rate         = av_int2double(avio_rb64(pb));
  72         st->codec->channels = avio_rb32(pb);
  73         comment_size        = avio_rb32(pb);
  74     }
  75
  76     if (comment_size > 0xFFFFFFFFU - SOX_FIXED_HDR - 4U) {
  77         av_log(s, AV_LOG_ERROR, "invalid comment size (%u)\n", comment_size);
  78         return -1;
  79     }
  80
  81     if (sample_rate <= 0 || sample_rate > INT_MAX) {
  82         av_log(s, AV_LOG_ERROR, "invalid sample rate (%f)\n", sample_rate);
  83         return -1;
  84     }
  85
  86     sample_rate_frac = sample_rate - floor(sample_rate);
  87     if (sample_rate_frac)
  88         av_log(s, AV_LOG_WARNING,
  89                "truncating fractional part of sample rate (%f)\n",
  90                sample_rate_frac);
  91
  92     if ((header_size + 4) & 7 || header_size < SOX_FIXED_HDR + comment_size
  93         || st->codec->channels > 65535) /* Reserve top 16 bits */ {
  94         av_log(s, AV_LOG_ERROR, "invalid header\n");
  95         return -1;
  96     }
  97
  98     if (comment_size && comment_size < UINT_MAX) {
  99         char *comment = av_malloc(comment_size+1);
 100         if (avio_read(pb, comment, comment_size) != comment_size) {
 101             av_freep(&comment);
 102             return AVERROR(EIO);
 103         }
 104         comment[comment_size] = 0;
 105
 106         av_dict_set(&s->metadata, "comment", comment,
 107                                AV_DICT_DONT_STRDUP_VAL);
 108     }
 109
 110     avio_skip(pb, header_size - SOX_FIXED_HDR - comment_size);
 111
 112     st->codec->sample_rate           = sample_rate;
 113     st->codec->bits_per_coded_sample = 32;
 114     st->codec->bit_rate              = st->codec->sample_rate *
 115                                        st->codec->bits_per_coded_sample *
 116                                        st->codec->channels;
 117     st->codec->block_align           = st->codec->bits_per_coded_sample *
 118                                        st->codec->channels / 8;
 119
 120     avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
 121
 122     return 0;
 123 }
 124
 125 #define SOX_SAMPLES 1024
 126
 127 static int sox_read_packet(AVFormatContext *s,
 128                            AVPacket *pkt)
 129 {
 130     int ret, size;
 131
 132     if (s->pb->eof_reached)
 133         return AVERROR_EOF;
 134
 135     size = SOX_SAMPLES*s->streams[0]->codec->block_align;
 136     ret = av_get_packet(s->pb, pkt, size);
 137     if (ret < 0)
 138         return AVERROR(EIO);
 139     pkt->stream_index = 0;
 140     pkt->size = ret;
 141
 142     return 0;
 143 }
 144
 145 AVInputFormat ff_sox_demuxer = {
 146     .name           = "sox",
 147     .long_name      = NULL_IF_CONFIG_SMALL("SoX native"),
 148     .read_probe     = sox_probe,
 149     .read_header    = sox_read_header,
 150     .read_packet    = sox_read_packet,
 151     .read_seek      = ff_pcm_read_seek,
 152 };