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 FFmpeg.
   9  *
  10  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  23  */
  24
  25 /**
  26  * SoX native format demuxer
  27  * @file libavformat/soxdec.c
  28  * @author Daniel Verkamp
  29  * @sa http://wiki.multimedia.cx/index.php?title=SoX_native_intermediate_format
  30  */
  31
  32 #include "libavutil/intreadwrite.h"
  33 #include "avformat.h"
  34 #include "raw.h"
  35 #include "sox.h"
  36
  37 static int sox_probe(AVProbeData *p)
  38 {
  39     if (AV_RL32(p->buf) == SOX_TAG || AV_RB32(p->buf) == SOX_TAG)
  40         return AVPROBE_SCORE_MAX;
  41     return 0;
  42 }
  43
  44 static int sox_read_header(AVFormatContext *s,
  45                            AVFormatParameters *ap)
  46 {
  47     ByteIOContext *pb = s->pb;
  48     unsigned header_size, comment_size;
  49     double sample_rate, sample_rate_frac;
  50     AVStream *st;
  51
  52     st = av_new_stream(s, 0);
  53     if (!st)
  54         return AVERROR(ENOMEM);
  55
  56     st->codec->codec_type = CODEC_TYPE_AUDIO;
  57
  58     if (get_le32(pb) == SOX_TAG) {
  59         st->codec->codec_id = CODEC_ID_PCM_S32LE;
  60         header_size         = get_le32(pb);
  61         url_fskip(pb, 8); /* sample count */
  62         sample_rate         = av_int2dbl(get_le64(pb));
  63         st->codec->channels = get_le32(pb);
  64         comment_size        = get_le32(pb);
  65     } else {
  66         st->codec->codec_id = CODEC_ID_PCM_S32BE;
  67         header_size         = get_be32(pb);
  68         url_fskip(pb, 8); /* sample count */
  69         sample_rate         = av_int2dbl(get_be64(pb));
  70         st->codec->channels = get_be32(pb);
  71         comment_size        = get_be32(pb);
  72     }
  73
  74     if (comment_size > 0xFFFFFFFFU - SOX_FIXED_HDR - 4U) {
  75         av_log(s, AV_LOG_ERROR, "invalid comment size (%u)\n", comment_size);
  76         return -1;
  77     }
  78
  79     if (sample_rate <= 0 || sample_rate > INT_MAX) {
  80         av_log(s, AV_LOG_ERROR, "invalid sample rate (%f)\n", sample_rate);
  81         return -1;
  82     }
  83
  84     sample_rate_frac = sample_rate - floor(sample_rate);
  85     if (sample_rate_frac)
  86         av_log(s, AV_LOG_WARNING,
  87                "truncating fractional part of sample rate (%f)\n",
  88                sample_rate_frac);
  89
  90     if ((header_size + 4) & 7 || header_size < SOX_FIXED_HDR + comment_size
  91         || st->codec->channels > 65535) /* Reserve top 16 bits */ {
  92         av_log(s, AV_LOG_ERROR, "invalid header\n");
  93         return -1;
  94     }
  95
  96     if (comment_size &&
  97         comment_size + FF_INPUT_BUFFER_PADDING_SIZE >= comment_size) {
  98         char *comment = av_mallocz(comment_size + FF_INPUT_BUFFER_PADDING_SIZE);
  99         if (get_buffer(pb, comment, comment_size) != comment_size) {
 100             av_freep(&comment);
 101             return AVERROR_IO;
 102         }
 103         av_metadata_set(&s->metadata, "comment", comment);
 104         av_freep(&comment);
 105     }
 106
 107     url_fskip(pb, header_size - SOX_FIXED_HDR - comment_size);
 108
 109     st->codec->sample_rate           = sample_rate;
 110     st->codec->sample_fmt            = SAMPLE_FMT_S32;
 111     st->codec->bits_per_coded_sample = 32;
 112     st->codec->bit_rate              = st->codec->sample_rate *
 113                                        st->codec->bits_per_coded_sample *
 114                                        st->codec->channels;
 115     st->codec->block_align           = st->codec->bits_per_coded_sample *
 116                                        st->codec->channels / 8;
 117
 118     av_set_pts_info(st, 64, 1, st->codec->sample_rate);
 119
 120     return 0;
 121 }
 122
 123 #define SOX_SAMPLES 1024
 124
 125 static int sox_read_packet(AVFormatContext *s,
 126                            AVPacket *pkt)
 127 {
 128     int ret, size;
 129
 130     if (url_feof(s->pb))
 131         return AVERROR_EOF;
 132
 133     size = SOX_SAMPLES*s->streams[0]->codec->block_align;
 134     ret = av_get_packet(s->pb, pkt, size);
 135     if (ret < 0)
 136         return AVERROR(EIO);
 137     pkt->stream_index = 0;
 138     pkt->size = ret;
 139
 140     return 0;
 141 }
 142
 143 AVInputFormat sox_demuxer = {
 144     "sox",
 145     NULL_IF_CONFIG_SMALL("SoX native format"),
 146     0,
 147     sox_probe,
 148     sox_read_header,
 149     sox_read_packet,
 150     NULL,
 151     pcm_read_seek,
 152 };