libavformat/nistspheredec.c

   1 /*
   2  * NIST Sphere 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/avstring.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 nist_probe(const AVProbeData *p)
  30 {
  31     if (AV_RL64(p->buf) == AV_RL64("NIST_1A\x0a"))
  32         return AVPROBE_SCORE_MAX;
  33     return 0;
  34 }
  35
  36 static int nist_read_header(AVFormatContext *s)
  37 {
  38     char buffer[256]= {0}, coding[32] = "pcm", format[32] = "01";
  39     int bps = 0, be = 0;
  40     int32_t header_size = -1;
  41     AVStream *st;
  42
  43     st = avformat_new_stream(s, NULL);
  44     if (!st)
  45         return AVERROR(ENOMEM);
  46
  47     st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
  48
  49     ff_get_line(s->pb, buffer, sizeof(buffer));
  50     ff_get_line(s->pb, buffer, sizeof(buffer));
  51     sscanf(buffer, "%"SCNd32, &header_size);
  52     if (header_size <= 0)
  53         return AVERROR_INVALIDDATA;
  54
  55     while (!avio_feof(s->pb)) {
  56         ff_get_line(s->pb, buffer, sizeof(buffer));
  57
  58         if (avio_tell(s->pb) >= header_size)
  59             return AVERROR_INVALIDDATA;
  60
  61         if (!memcmp(buffer, "end_head", 8)) {
  62             if (!st->codecpar->bits_per_coded_sample)
  63                 st->codecpar->bits_per_coded_sample = bps << 3;
  64
  65             if (!av_strcasecmp(coding, "pcm")) {
  66                 if (st->codecpar->codec_id == AV_CODEC_ID_NONE)
  67                     st->codecpar->codec_id = ff_get_pcm_codec_id(st->codecpar->bits_per_coded_sample,
  68                                                               0, be, 0xFFFF);
  69             } else if (!av_strcasecmp(coding, "alaw")) {
  70                 st->codecpar->codec_id = AV_CODEC_ID_PCM_ALAW;
  71             } else if (!av_strcasecmp(coding, "ulaw") ||
  72                        !av_strcasecmp(coding, "mu-law")) {
  73                 st->codecpar->codec_id = AV_CODEC_ID_PCM_MULAW;
  74             } else if (!av_strncasecmp(coding, "pcm,embedded-shorten", 20)) {
  75                 st->codecpar->codec_id = AV_CODEC_ID_SHORTEN;
  76                 if (ff_alloc_extradata(st->codecpar, 1))
  77                     st->codecpar->extradata[0] = 1;
  78             } else {
  79                 avpriv_request_sample(s, "coding %s", coding);
  80             }
  81
  82             avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
  83
  84             st->codecpar->block_align = st->codecpar->bits_per_coded_sample *
  85                                         st->codecpar->ch_layout.nb_channels / 8;
  86
  87             if (avio_tell(s->pb) > header_size)
  88                 return AVERROR_INVALIDDATA;
  89
  90             avio_skip(s->pb, header_size - avio_tell(s->pb));
  91
  92             return 0;
  93         } else if (!memcmp(buffer, "channel_count", 13)) {
  94             sscanf(buffer, "%*s %*s %u", &st->codecpar->ch_layout.nb_channels);
  95             if (st->codecpar->ch_layout.nb_channels <= 0 || st->codecpar->ch_layout.nb_channels > INT16_MAX)
  96                 return AVERROR_INVALIDDATA;
  97         } else if (!memcmp(buffer, "sample_byte_format", 18)) {
  98             sscanf(buffer, "%*s %*s %31s", format);
  99
 100             if (!av_strcasecmp(format, "01")) {
 101                 be = 0;
 102             } else if (!av_strcasecmp(format, "10")) {
 103                 be = 1;
 104             } else if (!av_strcasecmp(format, "mu-law")) {
 105                 st->codecpar->codec_id = AV_CODEC_ID_PCM_MULAW;
 106             } else if (av_strcasecmp(format, "1")) {
 107                 avpriv_request_sample(s, "sample byte format %s", format);
 108                 return AVERROR_PATCHWELCOME;
 109             }
 110         } else if (!memcmp(buffer, "sample_coding", 13)) {
 111             sscanf(buffer, "%*s %*s %31s", coding);
 112         } else if (!memcmp(buffer, "sample_count", 12)) {
 113             sscanf(buffer, "%*s %*s %"SCNd64, &st->duration);
 114         } else if (!memcmp(buffer, "sample_n_bytes", 14)) {
 115             sscanf(buffer, "%*s %*s %d", &bps);
 116             if (bps > INT16_MAX/8U)
 117                 return AVERROR_INVALIDDATA;
 118         } else if (!memcmp(buffer, "sample_rate", 11)) {
 119             sscanf(buffer, "%*s %*s %d", &st->codecpar->sample_rate);
 120         } else if (!memcmp(buffer, "sample_sig_bits", 15)) {
 121             sscanf(buffer, "%*s %*s %d", &st->codecpar->bits_per_coded_sample);
 122             if (st->codecpar->bits_per_coded_sample <= 0 || st->codecpar->bits_per_coded_sample > INT16_MAX)
 123                 return AVERROR_INVALIDDATA;
 124         } else {
 125             char key[32], value[32];
 126             if (sscanf(buffer, "%31s %*s %31s", key, value) == 2) {
 127                 av_dict_set(&s->metadata, key, value, AV_DICT_APPEND);
 128             } else {
 129                 av_log(s, AV_LOG_ERROR, "Failed to parse '%s' as metadata\n", buffer);
 130             }
 131         }
 132     }
 133
 134     return AVERROR_EOF;
 135 }
 136
 137 const FFInputFormat ff_nistsphere_demuxer = {
 138     .p.name         = "nistsphere",
 139     .p.long_name    = NULL_IF_CONFIG_SMALL("NIST SPeech HEader REsources"),
 140     .p.extensions   = "nist,sph",
 141     .p.flags        = AVFMT_GENERIC_INDEX,
 142     .read_probe     = nist_probe,
 143     .read_header    = nist_read_header,
 144     .read_packet    = ff_pcm_read_packet,
 145     .read_seek      = ff_pcm_read_seek,
 146 };