libavformat/thp.c

   1 /*
   2  * THP Demuxer
   3  * Copyright (c) 2007 Marco Gerards
   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/intreadwrite.h"
  23 #include "avformat.h"
  24
  25 typedef struct ThpDemuxContext {
  26     int              version;
  27     int              first_frame;
  28     int              first_framesz;
  29     int              last_frame;
  30     int              compoff;
  31     int              framecnt;
  32     AVRational       fps;
  33     int              frame;
  34     int              next_frame;
  35     int              next_framesz;
  36     int              video_stream_index;
  37     int              audio_stream_index;
  38     int              compcount;
  39     unsigned char    components[16];
  40     AVStream*        vst;
  41     int              has_audio;
  42     int              audiosize;
  43 } ThpDemuxContext;
  44
  45
  46 static int thp_probe(AVProbeData *p)
  47 {
  48     /* check file header */
  49     if (AV_RL32(p->buf) == MKTAG('T', 'H', 'P', '\0'))
  50         return AVPROBE_SCORE_MAX;
  51     else
  52         return 0;
  53 }
  54
  55 static int thp_read_header(AVFormatContext *s,
  56                            AVFormatParameters *ap)
  57 {
  58     ThpDemuxContext *thp = s->priv_data;
  59     AVStream *st;
  60     ByteIOContext *pb = s->pb;
  61     int i;
  62
  63     /* Read the file header.  */
  64                            get_be32(pb); /* Skip Magic.  */
  65     thp->version         = get_be32(pb);
  66
  67                            get_be32(pb); /* Max buf size.  */
  68                            get_be32(pb); /* Max samples.  */
  69
  70     thp->fps             = av_d2q(av_int2flt(get_be32(pb)), INT_MAX);
  71     thp->framecnt        = get_be32(pb);
  72     thp->first_framesz   = get_be32(pb);
  73                            get_be32(pb); /* Data size.  */
  74
  75     thp->compoff         = get_be32(pb);
  76                            get_be32(pb); /* offsetDataOffset.  */
  77     thp->first_frame     = get_be32(pb);
  78     thp->last_frame      = get_be32(pb);
  79
  80     thp->next_framesz    = thp->first_framesz;
  81     thp->next_frame      = thp->first_frame;
  82
  83     /* Read the component structure.  */
  84     url_fseek (pb, thp->compoff, SEEK_SET);
  85     thp->compcount       = get_be32(pb);
  86
  87     /* Read the list of component types.  */
  88     get_buffer(pb, thp->components, 16);
  89
  90     for (i = 0; i < thp->compcount; i++) {
  91         if (thp->components[i] == 0) {
  92             if (thp->vst != 0)
  93                 break;
  94
  95             /* Video component.  */
  96             st = av_new_stream(s, 0);
  97             if (!st)
  98                 return AVERROR(ENOMEM);
  99
 100             /* The denominator and numerator are switched because 1/fps
 101                is required.  */
 102             av_set_pts_info(st, 64, thp->fps.den, thp->fps.num);
 103             st->codec->codec_type = CODEC_TYPE_VIDEO;
 104             st->codec->codec_id = CODEC_ID_THP;
 105             st->codec->codec_tag = 0;  /* no fourcc */
 106             st->codec->width = get_be32(pb);
 107             st->codec->height = get_be32(pb);
 108             st->codec->sample_rate = av_q2d(thp->fps);
 109             thp->vst = st;
 110             thp->video_stream_index = st->index;
 111
 112             if (thp->version == 0x11000)
 113                 get_be32(pb); /* Unknown.  */
 114         } else if (thp->components[i] == 1) {
 115             if (thp->has_audio != 0)
 116                 break;
 117
 118             /* Audio component.  */
 119             st = av_new_stream(s, 0);
 120             if (!st)
 121                 return AVERROR(ENOMEM);
 122
 123             st->codec->codec_type = CODEC_TYPE_AUDIO;
 124             st->codec->codec_id = CODEC_ID_ADPCM_THP;
 125             st->codec->codec_tag = 0;  /* no fourcc */
 126             st->codec->channels    = get_be32(pb); /* numChannels.  */
 127             st->codec->sample_rate = get_be32(pb); /* Frequency.  */
 128
 129             av_set_pts_info(st, 64, 1, st->codec->sample_rate);
 130
 131             thp->audio_stream_index = st->index;
 132             thp->has_audio = 1;
 133         }
 134     }
 135
 136     return 0;
 137 }
 138
 139 static int thp_read_packet(AVFormatContext *s,
 140                             AVPacket *pkt)
 141 {
 142     ThpDemuxContext *thp = s->priv_data;
 143     ByteIOContext *pb = s->pb;
 144     int size;
 145     int ret;
 146
 147     if (thp->audiosize == 0) {
 148         /* Terminate when last frame is reached.  */
 149         if (thp->frame >= thp->framecnt)
 150             return AVERROR(EIO);
 151
 152         url_fseek(pb, thp->next_frame, SEEK_SET);
 153
 154         /* Locate the next frame and read out its size.  */
 155         thp->next_frame += thp->next_framesz;
 156         thp->next_framesz = get_be32(pb);
 157
 158                         get_be32(pb); /* Previous total size.  */
 159         size          = get_be32(pb); /* Total size of this frame.  */
 160
 161         /* Store the audiosize so the next time this function is called,
 162            the audio can be read.  */
 163         if (thp->has_audio)
 164             thp->audiosize = get_be32(pb); /* Audio size.  */
 165         else
 166             thp->frame++;
 167
 168         ret = av_get_packet(pb, pkt, size);
 169         if (ret != size) {
 170             av_free_packet(pkt);
 171             return AVERROR(EIO);
 172         }
 173
 174         pkt->stream_index = thp->video_stream_index;
 175     } else {
 176         ret = av_get_packet(pb, pkt, thp->audiosize);
 177         if (ret != thp->audiosize) {
 178             av_free_packet(pkt);
 179             return AVERROR(EIO);
 180         }
 181
 182         pkt->stream_index = thp->audio_stream_index;
 183         thp->audiosize = 0;
 184         thp->frame++;
 185     }
 186
 187     return 0;
 188 }
 189
 190 AVInputFormat thp_demuxer = {
 191     "thp",
 192     NULL_IF_CONFIG_SMALL("THP"),
 193     sizeof(ThpDemuxContext),
 194     thp_probe,
 195     thp_read_header,
 196     thp_read_packet
 197 };