libavformat/wsddec.c

   1 /*
   2  * Wideband Single-bit Data (WSD) demuxer
   3  * Copyright (c) 2014 Peter Ross
   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/channel_layout.h"
  23 #include "libavutil/intreadwrite.h"
  24 #include "libavutil/mem.h"
  25 #include "libavutil/timecode.h"
  26 #include "avformat.h"
  27 #include "avio_internal.h"
  28 #include "demux.h"
  29 #include "rawdec.h"
  30
  31 static int wsd_probe(const AVProbeData *p)
  32 {
  33     if (p->buf_size < 45 || memcmp(p->buf, "1bit", 4) ||
  34         !AV_RB32(p->buf + 36) || !p->buf[44] ||
  35         (p->buf[0] >= 0x10 && (AV_RB32(p->buf + 20) < 0x80 || AV_RB32(p->buf + 24) < 0x80)))
  36        return 0;
  37     return AVPROBE_SCORE_MAX;
  38 }
  39
  40 static int empty_string(const char *buf, unsigned size)
  41 {
  42     while (size--) {
  43        if (*buf++ != ' ')
  44            return 0;
  45     }
  46     return 1;
  47 }
  48
  49 static int wsd_to_av_channel_layoyt(AVFormatContext *s, int bit)
  50 {
  51     switch (bit) {
  52     case 2: return AV_CH_BACK_RIGHT;
  53     case 3:
  54         avpriv_request_sample(s, "Rr-middle");
  55         break;
  56     case 4: return AV_CH_BACK_CENTER;
  57     case 5:
  58         avpriv_request_sample(s, "Lr-middle");
  59         break;
  60     case 6: return AV_CH_BACK_LEFT;
  61     case 24: return AV_CH_LOW_FREQUENCY;
  62     case 26: return AV_CH_FRONT_RIGHT;
  63     case 27: return AV_CH_FRONT_RIGHT_OF_CENTER;
  64     case 28: return AV_CH_FRONT_CENTER;
  65     case 29: return AV_CH_FRONT_LEFT_OF_CENTER;
  66     case 30: return AV_CH_FRONT_LEFT;
  67     default:
  68         av_log(s, AV_LOG_WARNING, "reserved channel assignment\n");
  69         break;
  70     }
  71     return 0;
  72 }
  73
  74 static int get_metadata(AVFormatContext *s, const char *const tag, const unsigned size)
  75 {
  76     uint8_t *buf;
  77     int ret;
  78     if (!(size + 1))
  79         return AVERROR(ENOMEM);
  80
  81     buf = av_malloc(size + 1);
  82     if (!buf)
  83         return AVERROR(ENOMEM);
  84
  85     if ((ret = avio_read(s->pb, buf, size)) < 0) {
  86         av_free(buf);
  87         return ret;
  88     }
  89
  90     if (empty_string(buf, size)) {
  91         av_free(buf);
  92         return 0;
  93     }
  94
  95     buf[size] = 0;
  96     av_dict_set(&s->metadata, tag, buf, AV_DICT_DONT_STRDUP_VAL);
  97     return 0;
  98 }
  99
 100 static int wsd_read_header(AVFormatContext *s)
 101 {
 102     AVIOContext *pb = s->pb;
 103     AVStream *st;
 104     int version;
 105     uint32_t text_offset, data_offset, channel_assign;
 106     char playback_time[AV_TIMECODE_STR_SIZE];
 107
 108     st = avformat_new_stream(s, NULL);
 109     if (!st)
 110         return AVERROR(ENOMEM);
 111
 112     avio_skip(pb, 8);
 113     version = avio_r8(pb);
 114     av_log(s, AV_LOG_DEBUG, "version: %i.%i\n", version >> 4, version & 0xF);
 115     avio_skip(pb, 11);
 116
 117     if (version < 0x10) {
 118         text_offset = 0x80;
 119         data_offset = 0x800;
 120         avio_skip(pb, 8);
 121     } else {
 122         text_offset = avio_rb32(pb);
 123         data_offset = avio_rb32(pb);
 124     }
 125
 126     avio_skip(pb, 4);
 127     av_timecode_make_smpte_tc_string2(playback_time, (AVRational){1,1}, avio_rb32(pb) & 0x00ffffffU, 1, 1);
 128     av_dict_set(&s->metadata, "playback_time", playback_time, 0);
 129
 130     st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
 131     st->codecpar->codec_id    = AV_CODEC_ID_DSD_MSBF;
 132     st->codecpar->sample_rate = avio_rb32(pb) / 8;
 133     avio_skip(pb, 4);
 134     st->codecpar->ch_layout.nb_channels = avio_r8(pb) & 0xF;
 135     st->codecpar->bit_rate    = (int64_t)st->codecpar->ch_layout.nb_channels *
 136                                 st->codecpar->sample_rate * 8LL;
 137     if (!st->codecpar->ch_layout.nb_channels)
 138         return AVERROR_INVALIDDATA;
 139
 140     avio_skip(pb, 3);
 141     channel_assign         = avio_rb32(pb);
 142     if (!(channel_assign & 1)) {
 143         uint64_t ch_mask = 0;
 144         int i;
 145         for (i = 1; i < 32; i++)
 146             if ((channel_assign >> i) & 1)
 147                 ch_mask |= wsd_to_av_channel_layoyt(s, i);
 148         av_channel_layout_from_mask(&st->codecpar->ch_layout, ch_mask);
 149     }
 150
 151     avio_skip(pb, 16);
 152     if (avio_rb32(pb))
 153        avpriv_request_sample(s, "emphasis");
 154
 155     if (avio_seek(pb, text_offset, SEEK_SET) >= 0) {
 156         get_metadata(s, "title",       128);
 157         get_metadata(s, "composer",    128);
 158         get_metadata(s, "song_writer", 128);
 159         get_metadata(s, "artist",      128);
 160         get_metadata(s, "album",       128);
 161         get_metadata(s, "genre",        32);
 162         get_metadata(s, "date",         32);
 163         get_metadata(s, "location",     32);
 164         get_metadata(s, "comment",     512);
 165         get_metadata(s, "user",        512);
 166     }
 167
 168     return avio_seek(pb, data_offset, SEEK_SET);
 169 }
 170
 171 const FFInputFormat ff_wsd_demuxer = {
 172     .p.name         = "wsd",
 173     .p.long_name    = NULL_IF_CONFIG_SMALL("Wideband Single-bit Data (WSD)"),
 174     .p.extensions   = "wsd",
 175     .p.flags        = AVFMT_GENERIC_INDEX | AVFMT_NO_BYTE_SEEK,
 176     .p.priv_class   = &ff_raw_demuxer_class,
 177     .read_probe   = wsd_probe,
 178     .read_header  = wsd_read_header,
 179     .read_packet  = ff_raw_read_partial_packet,
 180     .raw_codec_id = AV_CODEC_ID_DSD_MSBF,
 181     .priv_data_size = sizeof(FFRawDemuxerContext),
 182 };