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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 vmd_frame {
41  int64_t frame_offset;
42  unsigned int frame_size;
43  int64_t pts;
44  int keyframe;
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, sample_rate;
68  if (p->buf_size < 806)
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  sample_rate = AV_RL16(&p->buf[804]);
77  if ((!w || w > 2048 || !h || h > 2048) &&
78  sample_rate != 22050)
79  return 0;
80 
81  /* only return half certainty since this check is a bit sketchy */
83 }
84 
86 {
87  VmdDemuxContext *vmd = s->priv_data;
88  AVIOContext *pb = s->pb;
89  AVStream *st = NULL, *vst = NULL;
90  unsigned int toc_offset;
91  unsigned char *raw_frame_table;
92  int raw_frame_table_size;
93  int64_t current_offset;
94  int i, j, ret;
95  int width, height;
96  unsigned int total_frames;
97  int64_t current_audio_pts = 0;
98  unsigned char chunk[BYTES_PER_FRAME_RECORD];
99  int num, den;
100  int sound_buffers;
101 
102  /* fetch the main header, including the 2 header length bytes */
103  avio_seek(pb, 0, SEEK_SET);
105  return AVERROR(EIO);
106 
107  width = AV_RL16(&vmd->vmd_header[12]);
108  height = AV_RL16(&vmd->vmd_header[14]);
109  if (width && height) {
110  if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3') {
111  vmd->is_indeo3 = 1;
112  } else {
113  vmd->is_indeo3 = 0;
114  }
115  /* start up the decoders */
116  vst = avformat_new_stream(s, NULL);
117  if (!vst)
118  return AVERROR(ENOMEM);
119  avpriv_set_pts_info(vst, 33, 1, 10);
120  vmd->video_stream_index = vst->index;
121  vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
122  vst->codec->codec_id = vmd->is_indeo3 ? AV_CODEC_ID_INDEO3 : AV_CODEC_ID_VMDVIDEO;
123  vst->codec->codec_tag = 0; /* no fourcc */
124  vst->codec->width = width;
125  vst->codec->height = height;
126  if(vmd->is_indeo3 && vst->codec->width > 320){
127  vst->codec->width >>= 1;
128  vst->codec->height >>= 1;
129  }
130  if (ff_alloc_extradata(vst->codec, VMD_HEADER_SIZE))
131  return AVERROR(ENOMEM);
132  memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
133  }
134 
135  /* if sample rate is 0, assume no audio */
136  vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);
137  if (vmd->sample_rate) {
138  st = avformat_new_stream(s, NULL);
139  if (!st)
140  return AVERROR(ENOMEM);
141  vmd->audio_stream_index = st->index;
144  st->codec->codec_tag = 0; /* no fourcc */
145  if (vmd->vmd_header[811] & 0x80) {
146  st->codec->channels = 2;
148  } else {
149  st->codec->channels = 1;
151  }
152  st->codec->sample_rate = vmd->sample_rate;
153  st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);
154  if (st->codec->block_align & 0x8000) {
155  st->codec->bits_per_coded_sample = 16;
156  st->codec->block_align = -(st->codec->block_align - 0x10000);
157  } else {
158  st->codec->bits_per_coded_sample = 8;
159  }
160  st->codec->bit_rate = st->codec->sample_rate *
162 
163  /* calculate pts */
164  num = st->codec->block_align;
165  den = st->codec->sample_rate * st->codec->channels;
166  av_reduce(&num, &den, num, den, (1UL<<31)-1);
167  if (vst)
168  avpriv_set_pts_info(vst, 33, num, den);
169  avpriv_set_pts_info(st, 33, num, den);
170  }
171 
172  toc_offset = AV_RL32(&vmd->vmd_header[812]);
173  vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
174  vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);
175  avio_seek(pb, toc_offset, SEEK_SET);
176 
177  raw_frame_table = NULL;
178  vmd->frame_table = NULL;
179  sound_buffers = AV_RL16(&vmd->vmd_header[808]);
180  raw_frame_table_size = vmd->frame_count * 6;
181  if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){
182  av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
183  return -1;
184  }
185  raw_frame_table = av_malloc(raw_frame_table_size);
186  vmd->frame_table = av_malloc_array(vmd->frame_count * vmd->frames_per_block + sound_buffers, sizeof(vmd_frame));
187  if (!raw_frame_table || !vmd->frame_table) {
188  ret = AVERROR(ENOMEM);
189  goto error;
190  }
191  if (avio_read(pb, raw_frame_table, raw_frame_table_size) !=
192  raw_frame_table_size) {
193  ret = AVERROR(EIO);
194  goto error;
195  }
196 
197  total_frames = 0;
198  for (i = 0; i < vmd->frame_count; i++) {
199 
200  current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);
201 
202  /* handle each entry in index block */
203  for (j = 0; j < vmd->frames_per_block; j++) {
204  int type;
205  uint32_t size;
206 
207  if ((ret = avio_read(pb, chunk, BYTES_PER_FRAME_RECORD)) != BYTES_PER_FRAME_RECORD) {
208  av_log(s, AV_LOG_ERROR, "Failed to read frame record\n");
209  if (ret >= 0)
210  ret = AVERROR_INVALIDDATA;
211  goto error;
212  }
213  type = chunk[0];
214  size = AV_RL32(&chunk[2]);
215  if (size > INT_MAX / 2) {
216  av_log(s, AV_LOG_ERROR, "Invalid frame size\n");
217  ret = AVERROR_INVALIDDATA;
218  goto error;
219  }
220  if(!size && type != 1)
221  continue;
222  switch(type) {
223  case 1: /* Audio Chunk */
224  if (!st) break;
225  /* first audio chunk contains several audio buffers */
226  vmd->frame_table[total_frames].frame_offset = current_offset;
227  vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
228  vmd->frame_table[total_frames].frame_size = size;
229  memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
230  vmd->frame_table[total_frames].pts = current_audio_pts;
231  total_frames++;
232  if(!current_audio_pts)
233  current_audio_pts += sound_buffers - 1;
234  else
235  current_audio_pts++;
236  break;
237  case 2: /* Video Chunk */
238  vmd->frame_table[total_frames].frame_offset = current_offset;
239  vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
240  vmd->frame_table[total_frames].frame_size = size;
241  memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
242  vmd->frame_table[total_frames].pts = i;
243  total_frames++;
244  break;
245  }
246  current_offset += size;
247  }
248  }
249 
250  av_free(raw_frame_table);
251 
252  vmd->current_frame = 0;
253  vmd->frame_count = total_frames;
254 
255  return 0;
256 
257 error:
258  av_freep(&raw_frame_table);
259  av_freep(&vmd->frame_table);
260  return ret;
261 }
262 
264  AVPacket *pkt)
265 {
266  VmdDemuxContext *vmd = s->priv_data;
267  AVIOContext *pb = s->pb;
268  int ret = 0;
269  vmd_frame *frame;
270 
271  if (vmd->current_frame >= vmd->frame_count)
272  return AVERROR_EOF;
273 
274  frame = &vmd->frame_table[vmd->current_frame];
275  /* position the stream (will probably be there already) */
276  avio_seek(pb, frame->frame_offset, SEEK_SET);
277 
278  if(ffio_limit(pb, frame->frame_size) != frame->frame_size)
279  return AVERROR(EIO);
281  return AVERROR(ENOMEM);
282  pkt->pos= avio_tell(pb);
283  memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
284  if(vmd->is_indeo3 && frame->frame_record[0] == 0x02)
285  ret = avio_read(pb, pkt->data, frame->frame_size);
286  else
287  ret = avio_read(pb, pkt->data + BYTES_PER_FRAME_RECORD,
288  frame->frame_size);
289 
290  if (ret != frame->frame_size) {
291  av_free_packet(pkt);
292  ret = AVERROR(EIO);
293  }
294  pkt->stream_index = frame->stream_index;
295  pkt->pts = frame->pts;
296  av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
297  (frame->frame_record[0] == 0x02) ? "video" : "audio",
299  pkt->pts);
300 
301  vmd->current_frame++;
302 
303  return ret;
304 }
305 
307 {
308  VmdDemuxContext *vmd = s->priv_data;
309 
310  av_freep(&vmd->frame_table);
311 
312  return 0;
313 }
314 
316  .name = "vmd",
317  .long_name = NULL_IF_CONFIG_SMALL("Sierra VMD"),
318  .priv_data_size = sizeof(VmdDemuxContext),
323 };