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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
30 #include "libavutil/intreadwrite.h"
31 #include "avformat.h"
32 #include "internal.h"
33 
34 #define VMD_HEADER_SIZE 0x0330
35 #define BYTES_PER_FRAME_RECORD 16
36 
37 typedef struct {
39  int64_t frame_offset;
40  unsigned int frame_size;
41  int64_t pts;
42  int keyframe;
43  unsigned char frame_record[BYTES_PER_FRAME_RECORD];
44 } vmd_frame;
45 
46 typedef struct VmdDemuxContext {
49 
50  unsigned int frame_count;
51  unsigned int frames_per_block;
53  unsigned int current_frame;
54  int is_indeo3;
55 
58  int skiphdr;
59 
60  unsigned char vmd_header[VMD_HEADER_SIZE];
62 
63 static int vmd_probe(AVProbeData *p)
64 {
65  int w, h;
66  if (p->buf_size < 16)
67  return 0;
68  /* check if the first 2 bytes of the file contain the appropriate size
69  * of a VMD header chunk */
70  if (AV_RL16(&p->buf[0]) != VMD_HEADER_SIZE - 2)
71  return 0;
72  w = AV_RL16(&p->buf[12]);
73  h = AV_RL16(&p->buf[14]);
74  if (!w || w > 2048 || !h || h > 2048)
75  return 0;
76 
77  /* only return half certainty since this check is a bit sketchy */
78  return AVPROBE_SCORE_MAX / 2;
79 }
80 
83 {
84  VmdDemuxContext *vmd = s->priv_data;
85  AVIOContext *pb = s->pb;
86  AVStream *st = NULL, *vst;
87  unsigned int toc_offset;
88  unsigned char *raw_frame_table;
89  int raw_frame_table_size;
90  int64_t current_offset;
91  int i, j;
92  unsigned int total_frames;
93  int64_t current_audio_pts = 0;
94  unsigned char chunk[BYTES_PER_FRAME_RECORD];
95  int num, den;
96  int sound_buffers;
97 
98  /* fetch the main header, including the 2 header length bytes */
99  avio_seek(pb, 0, SEEK_SET);
101  return AVERROR(EIO);
102 
103  if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3')
104  vmd->is_indeo3 = 1;
105  else
106  vmd->is_indeo3 = 0;
107  /* start up the decoders */
108  vst = avformat_new_stream(s, NULL);
109  if (!vst)
110  return AVERROR(ENOMEM);
111  avpriv_set_pts_info(vst, 33, 1, 10);
112  vmd->video_stream_index = vst->index;
113  vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
114  vst->codec->codec_id = vmd->is_indeo3 ? CODEC_ID_INDEO3 : CODEC_ID_VMDVIDEO;
115  vst->codec->codec_tag = 0; /* no fourcc */
116  vst->codec->width = AV_RL16(&vmd->vmd_header[12]);
117  vst->codec->height = AV_RL16(&vmd->vmd_header[14]);
118  if(vmd->is_indeo3 && vst->codec->width > 320){
119  vst->codec->width >>= 1;
120  vst->codec->height >>= 1;
121  }
122  vst->codec->extradata_size = VMD_HEADER_SIZE;
123  vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
124  memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
125 
126  /* if sample rate is 0, assume no audio */
127  vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);
128  if (vmd->sample_rate) {
129  st = avformat_new_stream(s, NULL);
130  if (!st)
131  return AVERROR(ENOMEM);
132  vmd->audio_stream_index = st->index;
135  st->codec->codec_tag = 0; /* no fourcc */
136  st->codec->channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
137  st->codec->sample_rate = vmd->sample_rate;
138  st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);
139  if (st->codec->block_align & 0x8000) {
140  st->codec->bits_per_coded_sample = 16;
141  st->codec->block_align = -(st->codec->block_align - 0x10000);
142  } else {
143  st->codec->bits_per_coded_sample = 8;
144  }
145  st->codec->bit_rate = st->codec->sample_rate *
147 
148  /* calculate pts */
149  num = st->codec->block_align;
150  den = st->codec->sample_rate * st->codec->channels;
151  av_reduce(&den, &num, den, num, (1UL<<31)-1);
152  avpriv_set_pts_info(vst, 33, num, den);
153  avpriv_set_pts_info(st, 33, num, den);
154  }
155 
156  toc_offset = AV_RL32(&vmd->vmd_header[812]);
157  vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
158  vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);
159  avio_seek(pb, toc_offset, SEEK_SET);
160 
161  raw_frame_table = NULL;
162  vmd->frame_table = NULL;
163  sound_buffers = AV_RL16(&vmd->vmd_header[808]);
164  raw_frame_table_size = vmd->frame_count * 6;
165  if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){
166  av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
167  return -1;
168  }
169  raw_frame_table = av_malloc(raw_frame_table_size);
170  vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame));
171  if (!raw_frame_table || !vmd->frame_table) {
172  av_free(raw_frame_table);
173  av_free(vmd->frame_table);
174  return AVERROR(ENOMEM);
175  }
176  if (avio_read(pb, raw_frame_table, raw_frame_table_size) !=
177  raw_frame_table_size) {
178  av_free(raw_frame_table);
179  av_free(vmd->frame_table);
180  return AVERROR(EIO);
181  }
182 
183  total_frames = 0;
184  for (i = 0; i < vmd->frame_count; i++) {
185 
186  current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);
187 
188  /* handle each entry in index block */
189  for (j = 0; j < vmd->frames_per_block; j++) {
190  int type;
191  uint32_t size;
192 
193  avio_read(pb, chunk, BYTES_PER_FRAME_RECORD);
194  type = chunk[0];
195  size = AV_RL32(&chunk[2]);
196  if(!size && type != 1)
197  continue;
198  switch(type) {
199  case 1: /* Audio Chunk */
200  if (!st) break;
201  /* first audio chunk contains several audio buffers */
202  vmd->frame_table[total_frames].frame_offset = current_offset;
203  vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
204  vmd->frame_table[total_frames].frame_size = size;
205  memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
206  vmd->frame_table[total_frames].pts = current_audio_pts;
207  total_frames++;
208  if(!current_audio_pts)
209  current_audio_pts += sound_buffers - 1;
210  else
211  current_audio_pts++;
212  break;
213  case 2: /* Video Chunk */
214  vmd->frame_table[total_frames].frame_offset = current_offset;
215  vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
216  vmd->frame_table[total_frames].frame_size = size;
217  memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
218  vmd->frame_table[total_frames].pts = i;
219  total_frames++;
220  break;
221  }
222  current_offset += size;
223  }
224  }
225 
226  av_free(raw_frame_table);
227 
228  vmd->current_frame = 0;
229  vmd->frame_count = total_frames;
230 
231  return 0;
232 }
233 
235  AVPacket *pkt)
236 {
237  VmdDemuxContext *vmd = s->priv_data;
238  AVIOContext *pb = s->pb;
239  int ret = 0;
240  vmd_frame *frame;
241 
242  if (vmd->current_frame >= vmd->frame_count)
243  return AVERROR(EIO);
244 
245  frame = &vmd->frame_table[vmd->current_frame];
246  /* position the stream (will probably be there already) */
247  avio_seek(pb, frame->frame_offset, SEEK_SET);
248 
250  return AVERROR(ENOMEM);
251  pkt->pos= avio_tell(pb);
252  memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
253  if(vmd->is_indeo3 && frame->frame_record[0] == 0x02)
254  ret = avio_read(pb, pkt->data, frame->frame_size);
255  else
256  ret = avio_read(pb, pkt->data + BYTES_PER_FRAME_RECORD,
257  frame->frame_size);
258 
259  if (ret != frame->frame_size) {
260  av_free_packet(pkt);
261  ret = AVERROR(EIO);
262  }
263  pkt->stream_index = frame->stream_index;
264  pkt->pts = frame->pts;
265  av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
266  (frame->frame_record[0] == 0x02) ? "video" : "audio",
268  pkt->pts);
269 
270  vmd->current_frame++;
271 
272  return ret;
273 }
274 
276 {
277  VmdDemuxContext *vmd = s->priv_data;
278 
279  av_free(vmd->frame_table);
280 
281  return 0;
282 }
283 
285  .name = "vmd",
286  .long_name = NULL_IF_CONFIG_SMALL("Sierra VMD format"),
287  .priv_data_size = sizeof(VmdDemuxContext),
292 };