libavformat/sierravmd.c

   1 /*
   2  * Sierra VMD Format Demuxer
   3  * Copyright (c) 2004 The ffmpeg Project
   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 /**
  23  * @file sierravmd.c
  24  * Sierra VMD file demuxer
  25  * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
  26  * for more information on the Sierra VMD file format, visit:
  27  *   http://www.pcisys.net/~melanson/codecs/
  28  */
  29
  30 #include "avformat.h"
  31
  32 #define VMD_HEADER_SIZE 0x0330
  33 #define BYTES_PER_FRAME_RECORD 16
  34
  35 typedef struct {
  36   int stream_index;
  37   offset_t frame_offset;
  38   unsigned int frame_size;
  39   int64_t pts;
  40   int keyframe;
  41   unsigned char frame_record[BYTES_PER_FRAME_RECORD];
  42 } vmd_frame_t;
  43
  44 typedef struct VmdDemuxContext {
  45     int video_stream_index;
  46     int audio_stream_index;
  47
  48     unsigned int frame_count;
  49     unsigned int frames_per_block;
  50     vmd_frame_t *frame_table;
  51     unsigned int current_frame;
  52
  53     int sample_rate;
  54     int64_t audio_sample_counter;
  55     int skiphdr;
  56
  57     unsigned char vmd_header[VMD_HEADER_SIZE];
  58 } VmdDemuxContext;
  59
  60 static int vmd_probe(AVProbeData *p)
  61 {
  62     /* check if the first 2 bytes of the file contain the appropriate size
  63      * of a VMD header chunk */
  64     if (AV_RL16(&p->buf[0]) != VMD_HEADER_SIZE - 2)
  65         return 0;
  66
  67     /* only return half certainty since this check is a bit sketchy */
  68     return AVPROBE_SCORE_MAX / 2;
  69 }
  70
  71 static int vmd_read_header(AVFormatContext *s,
  72                            AVFormatParameters *ap)
  73 {
  74     VmdDemuxContext *vmd = s->priv_data;
  75     ByteIOContext *pb = s->pb;
  76     AVStream *st = NULL, *vst;
  77     unsigned int toc_offset;
  78     unsigned char *raw_frame_table;
  79     int raw_frame_table_size;
  80     offset_t current_offset;
  81     int i, j;
  82     unsigned int total_frames;
  83     int64_t pts_inc = 1;
  84     int64_t current_video_pts = 0, current_audio_pts = 0;
  85     unsigned char chunk[BYTES_PER_FRAME_RECORD];
  86     int num, den;
  87     int sound_buffers;
  88
  89     /* fetch the main header, including the 2 header length bytes */
  90     url_fseek(pb, 0, SEEK_SET);
  91     if (get_buffer(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)
  92         return AVERROR(EIO);
  93
  94     /* start up the decoders */
  95     vst = av_new_stream(s, 0);
  96     if (!vst)
  97         return AVERROR(ENOMEM);
  98     av_set_pts_info(vst, 33, 1, 10);
  99     vmd->video_stream_index = vst->index;
 100     vst->codec->codec_type = CODEC_TYPE_VIDEO;
 101     vst->codec->codec_id = CODEC_ID_VMDVIDEO;
 102     vst->codec->codec_tag = 0;  /* no fourcc */
 103     vst->codec->width = AV_RL16(&vmd->vmd_header[12]);
 104     vst->codec->height = AV_RL16(&vmd->vmd_header[14]);
 105     vst->codec->extradata_size = VMD_HEADER_SIZE;
 106     vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
 107     memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
 108
 109     /* if sample rate is 0, assume no audio */
 110     vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);
 111     if (vmd->sample_rate) {
 112         st = av_new_stream(s, 0);
 113         if (!st)
 114             return AVERROR(ENOMEM);
 115         vmd->audio_stream_index = st->index;
 116         st->codec->codec_type = CODEC_TYPE_AUDIO;
 117         st->codec->codec_id = CODEC_ID_VMDAUDIO;
 118         st->codec->codec_tag = 0;  /* no fourcc */
 119         st->codec->channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
 120         st->codec->sample_rate = vmd->sample_rate;
 121         st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);
 122         if (st->codec->block_align & 0x8000) {
 123             st->codec->bits_per_sample = 16;
 124             st->codec->block_align = -(st->codec->block_align - 0x10000);
 125         } else {
 126             st->codec->bits_per_sample = 8;
 127         }
 128         st->codec->bit_rate = st->codec->sample_rate *
 129             st->codec->bits_per_sample * st->codec->channels;
 130
 131         /* calculate pts */
 132         num = st->codec->block_align;
 133         den = st->codec->sample_rate * st->codec->channels;
 134         av_reduce(&den, &num, den, num, (1UL<<31)-1);
 135         av_set_pts_info(vst, 33, num, den);
 136         av_set_pts_info(st, 33, num, den);
 137         pts_inc = num;
 138     }
 139
 140     toc_offset = AV_RL32(&vmd->vmd_header[812]);
 141     vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
 142     vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);
 143     url_fseek(pb, toc_offset, SEEK_SET);
 144
 145     raw_frame_table = NULL;
 146     vmd->frame_table = NULL;
 147     sound_buffers = AV_RL16(&vmd->vmd_header[808]);
 148     raw_frame_table_size = vmd->frame_count * 6;
 149     if(vmd->frame_count * vmd->frames_per_block  >= UINT_MAX / sizeof(vmd_frame_t)){
 150         av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
 151         return -1;
 152     }
 153     raw_frame_table = av_malloc(raw_frame_table_size);
 154     vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame_t));
 155     if (!raw_frame_table || !vmd->frame_table) {
 156         av_free(raw_frame_table);
 157         av_free(vmd->frame_table);
 158         return AVERROR(ENOMEM);
 159     }
 160     if (get_buffer(pb, raw_frame_table, raw_frame_table_size) !=
 161         raw_frame_table_size) {
 162         av_free(raw_frame_table);
 163         av_free(vmd->frame_table);
 164         return AVERROR(EIO);
 165     }
 166
 167     total_frames = 0;
 168     for (i = 0; i < vmd->frame_count; i++) {
 169
 170         current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);
 171
 172         /* handle each entry in index block */
 173         for (j = 0; j < vmd->frames_per_block; j++) {
 174             int type;
 175             uint32_t size;
 176
 177             get_buffer(pb, chunk, BYTES_PER_FRAME_RECORD);
 178             type = chunk[0];
 179             size = AV_RL32(&chunk[2]);
 180             if(!size)
 181                 continue;
 182             switch(type) {
 183             case 1: /* Audio Chunk */
 184                 if (!st) break;
 185                 /* first audio chunk contains several audio buffers */
 186                 if(current_audio_pts){
 187                     vmd->frame_table[total_frames].frame_offset = current_offset;
 188                     vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
 189                     vmd->frame_table[total_frames].frame_size = size;
 190                     memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
 191                     vmd->frame_table[total_frames].pts = current_audio_pts;
 192                     total_frames++;
 193                     current_audio_pts += pts_inc;
 194                 }else{
 195                     uint32_t flags;
 196                     int k;
 197                     int noff;
 198                     int64_t pos;
 199
 200                     pos = url_ftell(pb);
 201                     url_fseek(pb, current_offset, SEEK_SET);
 202                     flags = get_le32(pb);
 203                     noff = 4;
 204                     url_fseek(pb, pos, SEEK_SET);
 205                     av_log(s, AV_LOG_DEBUG, "Sound mapping = %08X (%i bufs)\n", flags, sound_buffers);
 206                     for(k = 0; k < sound_buffers - 1; k++){
 207                         if(flags & 1) { /* silent block */
 208                             vmd->frame_table[total_frames].frame_size = 0;
 209                         }else{
 210                             vmd->frame_table[total_frames].frame_size = st->codec->block_align + (st->codec->block_align & 1);
 211                         }
 212                         noff += vmd->frame_table[total_frames].frame_size;
 213                         vmd->frame_table[total_frames].frame_offset = current_offset + noff;
 214                         vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
 215                         memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
 216                         vmd->frame_table[total_frames].pts = current_audio_pts;
 217                         total_frames++;
 218                         current_audio_pts += pts_inc;
 219                         flags >>= 1;
 220                     }
 221                 }
 222                 break;
 223             case 2: /* Video Chunk */
 224                 vmd->frame_table[total_frames].frame_offset = current_offset;
 225                 vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
 226                 vmd->frame_table[total_frames].frame_size = size;
 227                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
 228                 vmd->frame_table[total_frames].pts = current_video_pts;
 229                 total_frames++;
 230                 break;
 231             }
 232             current_offset += size;
 233         }
 234         current_video_pts += pts_inc;
 235     }
 236
 237     av_free(raw_frame_table);
 238
 239     vmd->current_frame = 0;
 240     vmd->frame_count = total_frames;
 241
 242     return 0;
 243 }
 244
 245 static int vmd_read_packet(AVFormatContext *s,
 246                            AVPacket *pkt)
 247 {
 248     VmdDemuxContext *vmd = s->priv_data;
 249     ByteIOContext *pb = s->pb;
 250     int ret = 0;
 251     vmd_frame_t *frame;
 252
 253     if (vmd->current_frame >= vmd->frame_count)
 254         return AVERROR(EIO);
 255
 256     frame = &vmd->frame_table[vmd->current_frame];
 257     /* position the stream (will probably be there already) */
 258     url_fseek(pb, frame->frame_offset, SEEK_SET);
 259
 260     if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD))
 261         return AVERROR(ENOMEM);
 262     pkt->pos= url_ftell(pb);
 263     memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
 264     ret = get_buffer(pb, pkt->data + BYTES_PER_FRAME_RECORD,
 265         frame->frame_size);
 266
 267     if (ret != frame->frame_size) {
 268         av_free_packet(pkt);
 269         ret = AVERROR(EIO);
 270     }
 271     pkt->stream_index = frame->stream_index;
 272     pkt->pts = frame->pts;
 273     av_log(NULL, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
 274             (frame->frame_record[0] == 0x02) ? "video" : "audio",
 275             frame->frame_size + BYTES_PER_FRAME_RECORD,
 276             pkt->pts);
 277
 278     vmd->current_frame++;
 279
 280     return ret;
 281 }
 282
 283 static int vmd_read_close(AVFormatContext *s)
 284 {
 285     VmdDemuxContext *vmd = s->priv_data;
 286
 287     av_free(vmd->frame_table);
 288
 289     return 0;
 290 }
 291
 292 AVInputFormat vmd_demuxer = {
 293     "vmd",
 294     NULL_IF_CONFIG_SMALL("Sierra VMD format"),
 295     sizeof(VmdDemuxContext),
 296     vmd_probe,
 297     vmd_read_header,
 298     vmd_read_packet,
 299     vmd_read_close,
 300 };