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sierravmd.c
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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
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 
31 #include "libavutil/intreadwrite.h"
32 #include "avformat.h"
33 #include "internal.h"
34 #include "avio_internal.h"
35 
36 #define VMD_HEADER_SIZE 0x0330
37 #define BYTES_PER_FRAME_RECORD 16
38 
39 typedef struct {
41  int64_t frame_offset;
42  unsigned int frame_size;
43  int64_t pts;
44  int keyframe;
45  unsigned char frame_record[BYTES_PER_FRAME_RECORD];
46 } vmd_frame;
47 
48 typedef struct VmdDemuxContext {
51 
52  unsigned int frame_count;
53  unsigned int frames_per_block;
55  unsigned int current_frame;
56  int is_indeo3;
57 
60  int skiphdr;
61 
62  unsigned char vmd_header[VMD_HEADER_SIZE];
64 
65 static int vmd_probe(AVProbeData *p)
66 {
67  int w, h;
68  if (p->buf_size < 16)
69  return 0;
70  /* check if the first 2 bytes of the file contain the appropriate size
71  * of a VMD header chunk */
72  if (AV_RL16(&p->buf[0]) != VMD_HEADER_SIZE - 2)
73  return 0;
74  w = AV_RL16(&p->buf[12]);
75  h = AV_RL16(&p->buf[14]);
76  if (!w || w > 2048 || !h || h > 2048)
77  return 0;
78 
79  /* only return half certainty since this check is a bit sketchy */
80  return AVPROBE_SCORE_MAX / 2;
81 }
82 
84 {
85  VmdDemuxContext *vmd = s->priv_data;
86  AVIOContext *pb = s->pb;
87  AVStream *st = NULL, *vst;
88  unsigned int toc_offset;
89  unsigned char *raw_frame_table;
90  int raw_frame_table_size;
91  int64_t current_offset;
92  int i, j;
93  unsigned int total_frames;
94  int64_t current_audio_pts = 0;
95  unsigned char chunk[BYTES_PER_FRAME_RECORD];
96  int num, den;
97  int sound_buffers;
98 
99  /* fetch the main header, including the 2 header length bytes */
100  avio_seek(pb, 0, SEEK_SET);
102  return AVERROR(EIO);
103 
104  if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3')
105  vmd->is_indeo3 = 1;
106  else
107  vmd->is_indeo3 = 0;
108  /* start up the decoders */
109  vst = avformat_new_stream(s, NULL);
110  if (!vst)
111  return AVERROR(ENOMEM);
112  avpriv_set_pts_info(vst, 33, 1, 10);
113  vmd->video_stream_index = vst->index;
114  vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
115  vst->codec->codec_id = vmd->is_indeo3 ? AV_CODEC_ID_INDEO3 : AV_CODEC_ID_VMDVIDEO;
116  vst->codec->codec_tag = 0; /* no fourcc */
117  vst->codec->width = AV_RL16(&vmd->vmd_header[12]);
118  vst->codec->height = AV_RL16(&vmd->vmd_header[14]);
119  if(vmd->is_indeo3 && vst->codec->width > 320){
120  vst->codec->width >>= 1;
121  vst->codec->height >>= 1;
122  }
123  vst->codec->extradata_size = VMD_HEADER_SIZE;
124  vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
125  memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
126 
127  /* if sample rate is 0, assume no audio */
128  vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);
129  if (vmd->sample_rate) {
130  st = avformat_new_stream(s, NULL);
131  if (!st)
132  return AVERROR(ENOMEM);
133  vmd->audio_stream_index = st->index;
136  st->codec->codec_tag = 0; /* no fourcc */
137  if (vmd->vmd_header[811] & 0x80) {
138  st->codec->channels = 2;
140  } else {
141  st->codec->channels = 1;
143  }
144  st->codec->sample_rate = vmd->sample_rate;
145  st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);
146  if (st->codec->block_align & 0x8000) {
147  st->codec->bits_per_coded_sample = 16;
148  st->codec->block_align = -(st->codec->block_align - 0x10000);
149  } else {
150  st->codec->bits_per_coded_sample = 8;
151  }
152  st->codec->bit_rate = st->codec->sample_rate *
154 
155  /* calculate pts */
156  num = st->codec->block_align;
157  den = st->codec->sample_rate * st->codec->channels;
158  av_reduce(&num, &den, num, den, (1UL<<31)-1);
159  avpriv_set_pts_info(vst, 33, num, den);
160  avpriv_set_pts_info(st, 33, num, den);
161  }
162 
163  toc_offset = AV_RL32(&vmd->vmd_header[812]);
164  vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
165  vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);
166  avio_seek(pb, toc_offset, SEEK_SET);
167 
168  raw_frame_table = NULL;
169  vmd->frame_table = NULL;
170  sound_buffers = AV_RL16(&vmd->vmd_header[808]);
171  raw_frame_table_size = vmd->frame_count * 6;
172  if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){
173  av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
174  return -1;
175  }
176  raw_frame_table = av_malloc(raw_frame_table_size);
177  vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame));
178  if (!raw_frame_table || !vmd->frame_table) {
179  av_free(raw_frame_table);
180  av_free(vmd->frame_table);
181  return AVERROR(ENOMEM);
182  }
183  if (avio_read(pb, raw_frame_table, raw_frame_table_size) !=
184  raw_frame_table_size) {
185  av_free(raw_frame_table);
186  av_free(vmd->frame_table);
187  return AVERROR(EIO);
188  }
189 
190  total_frames = 0;
191  for (i = 0; i < vmd->frame_count; i++) {
192 
193  current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);
194 
195  /* handle each entry in index block */
196  for (j = 0; j < vmd->frames_per_block; j++) {
197  int type;
198  uint32_t size;
199 
200  avio_read(pb, chunk, BYTES_PER_FRAME_RECORD);
201  type = chunk[0];
202  size = AV_RL32(&chunk[2]);
203  if(!size && type != 1)
204  continue;
205  switch(type) {
206  case 1: /* Audio Chunk */
207  if (!st) break;
208  /* first audio chunk contains several audio buffers */
209  vmd->frame_table[total_frames].frame_offset = current_offset;
210  vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
211  vmd->frame_table[total_frames].frame_size = size;
212  memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
213  vmd->frame_table[total_frames].pts = current_audio_pts;
214  total_frames++;
215  if(!current_audio_pts)
216  current_audio_pts += sound_buffers - 1;
217  else
218  current_audio_pts++;
219  break;
220  case 2: /* Video Chunk */
221  vmd->frame_table[total_frames].frame_offset = current_offset;
222  vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
223  vmd->frame_table[total_frames].frame_size = size;
224  memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
225  vmd->frame_table[total_frames].pts = i;
226  total_frames++;
227  break;
228  }
229  current_offset += size;
230  }
231  }
232 
233  av_free(raw_frame_table);
234 
235  vmd->current_frame = 0;
236  vmd->frame_count = total_frames;
237 
238  return 0;
239 }
240 
242  AVPacket *pkt)
243 {
244  VmdDemuxContext *vmd = s->priv_data;
245  AVIOContext *pb = s->pb;
246  int ret = 0;
247  vmd_frame *frame;
248 
249  if (vmd->current_frame >= vmd->frame_count)
250  return AVERROR_EOF;
251 
252  frame = &vmd->frame_table[vmd->current_frame];
253  /* position the stream (will probably be there already) */
254  avio_seek(pb, frame->frame_offset, SEEK_SET);
255 
256  if(ffio_limit(pb, frame->frame_size) != frame->frame_size)
257  return AVERROR(EIO);
259  return AVERROR(ENOMEM);
260  pkt->pos= avio_tell(pb);
261  memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
262  if(vmd->is_indeo3 && frame->frame_record[0] == 0x02)
263  ret = avio_read(pb, pkt->data, frame->frame_size);
264  else
265  ret = avio_read(pb, pkt->data + BYTES_PER_FRAME_RECORD,
266  frame->frame_size);
267 
268  if (ret != frame->frame_size) {
269  av_free_packet(pkt);
270  ret = AVERROR(EIO);
271  }
272  pkt->stream_index = frame->stream_index;
273  pkt->pts = frame->pts;
274  av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
275  (frame->frame_record[0] == 0x02) ? "video" : "audio",
277  pkt->pts);
278 
279  vmd->current_frame++;
280 
281  return ret;
282 }
283 
285 {
286  VmdDemuxContext *vmd = s->priv_data;
287 
288  av_free(vmd->frame_table);
289 
290  return 0;
291 }
292 
294  .name = "vmd",
295  .long_name = NULL_IF_CONFIG_SMALL("Sierra VMD"),
296  .priv_data_size = sizeof(VmdDemuxContext),
301 };