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vmdvideo.c
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1 /*
2  * Sierra VMD video decoder
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 video decoder
25  * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
26  * for more information on the Sierra VMD format, visit:
27  * http://www.pcisys.net/~melanson/codecs/
28  *
29  * The video decoder outputs PAL8 colorspace data. The decoder expects
30  * a 0x330-byte VMD file header to be transmitted via extradata during
31  * codec initialization. Each encoded frame that is sent to this decoder
32  * is expected to be prepended with the appropriate 16-byte frame
33  * information record from the VMD file.
34  */
35 
36 #include <string.h>
37 
38 #include "libavutil/common.h"
39 #include "libavutil/intreadwrite.h"
40 
41 #include "avcodec.h"
42 #include "internal.h"
43 #include "bytestream.h"
44 
45 #define VMD_HEADER_SIZE 0x330
46 #define PALETTE_COUNT 256
47 
48 typedef struct VmdVideoContext {
49 
52 
53  const unsigned char *buf;
54  int size;
55 
56  unsigned char palette[PALETTE_COUNT * 4];
57  unsigned char *unpack_buffer;
59 
60  int x_off, y_off;
62 
63 #define QUEUE_SIZE 0x1000
64 #define QUEUE_MASK 0x0FFF
65 
66 static int lz_unpack(const unsigned char *src, int src_len,
67  unsigned char *dest, int dest_len)
68 {
69  unsigned char *d;
70  unsigned char *d_end;
71  unsigned char queue[QUEUE_SIZE];
72  unsigned int qpos;
73  unsigned int dataleft;
74  unsigned int chainofs;
75  unsigned int chainlen;
76  unsigned int speclen;
77  unsigned char tag;
78  unsigned int i, j;
79  GetByteContext gb;
80 
81  bytestream2_init(&gb, src, src_len);
82  d = dest;
83  d_end = d + dest_len;
84  dataleft = bytestream2_get_le32(&gb);
85  memset(queue, 0x20, QUEUE_SIZE);
86  if (bytestream2_get_bytes_left(&gb) < 4)
87  return AVERROR_INVALIDDATA;
88  if (bytestream2_peek_le32(&gb) == 0x56781234) {
89  bytestream2_skipu(&gb, 4);
90  qpos = 0x111;
91  speclen = 0xF + 3;
92  } else {
93  qpos = 0xFEE;
94  speclen = 100; /* no speclen */
95  }
96 
97  while (dataleft > 0 && bytestream2_get_bytes_left(&gb) > 0) {
98  tag = bytestream2_get_byteu(&gb);
99  if ((tag == 0xFF) && (dataleft > 8)) {
100  if (d_end - d < 8 || bytestream2_get_bytes_left(&gb) < 8)
101  return AVERROR_INVALIDDATA;
102  for (i = 0; i < 8; i++) {
103  queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
104  qpos &= QUEUE_MASK;
105  }
106  dataleft -= 8;
107  } else {
108  for (i = 0; i < 8; i++) {
109  if (dataleft == 0)
110  break;
111  if (tag & 0x01) {
112  if (d_end - d < 1 || bytestream2_get_bytes_left(&gb) < 1)
113  return AVERROR_INVALIDDATA;
114  queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
115  qpos &= QUEUE_MASK;
116  dataleft--;
117  } else {
118  chainofs = bytestream2_get_byte(&gb);
119  chainofs |= ((bytestream2_peek_byte(&gb) & 0xF0) << 4);
120  chainlen = (bytestream2_get_byte(&gb) & 0x0F) + 3;
121  if (chainlen == speclen) {
122  chainlen = bytestream2_get_byte(&gb) + 0xF + 3;
123  }
124  if (d_end - d < chainlen)
125  return AVERROR_INVALIDDATA;
126  for (j = 0; j < chainlen; j++) {
127  *d = queue[chainofs++ & QUEUE_MASK];
128  queue[qpos++] = *d++;
129  qpos &= QUEUE_MASK;
130  }
131  dataleft -= chainlen;
132  }
133  tag >>= 1;
134  }
135  }
136  }
137  return d - dest;
138 }
139 static int rle_unpack(const unsigned char *src, unsigned char *dest,
140  int src_count, int src_size, int dest_len)
141 {
142  unsigned char *pd;
143  int i, l, used = 0;
144  unsigned char *dest_end = dest + dest_len;
145  GetByteContext gb;
146  uint16_t run_val;
147 
148  bytestream2_init(&gb, src, src_size);
149  pd = dest;
150  if (src_count & 1) {
151  if (bytestream2_get_bytes_left(&gb) < 1)
152  return 0;
153  *pd++ = bytestream2_get_byteu(&gb);
154  used++;
155  }
156 
157  do {
158  if (bytestream2_get_bytes_left(&gb) < 1)
159  break;
160  l = bytestream2_get_byteu(&gb);
161  if (l & 0x80) {
162  l = (l & 0x7F) * 2;
163  if (dest_end - pd < l || bytestream2_get_bytes_left(&gb) < l)
164  return bytestream2_tell(&gb);
165  bytestream2_get_bufferu(&gb, pd, l);
166  pd += l;
167  } else {
168  if (dest_end - pd < 2*l || bytestream2_get_bytes_left(&gb) < 2)
169  return bytestream2_tell(&gb);
170  run_val = bytestream2_get_ne16(&gb);
171  for (i = 0; i < l; i++) {
172  AV_WN16(pd, run_val);
173  pd += 2;
174  }
175  l *= 2;
176  }
177  used += l;
178  } while (used < src_count);
179 
180  return bytestream2_tell(&gb);
181 }
182 
184 {
185  int i;
186  unsigned int *palette32;
187  unsigned char r, g, b;
188 
189  GetByteContext gb;
190 
191  unsigned char meth;
192  unsigned char *dp; /* pointer to current frame */
193  unsigned char *pp; /* pointer to previous frame */
194  unsigned char len;
195  int ofs;
196 
197  int frame_x, frame_y;
198  int frame_width, frame_height;
199 
200  frame_x = AV_RL16(&s->buf[6]);
201  frame_y = AV_RL16(&s->buf[8]);
202  frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
203  frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
204 
205  if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
206  (frame_x || frame_y)) {
207 
208  s->x_off = frame_x;
209  s->y_off = frame_y;
210  }
211  frame_x -= s->x_off;
212  frame_y -= s->y_off;
213 
214  if (frame_x < 0 || frame_width < 0 ||
215  frame_x >= s->avctx->width ||
216  frame_width > s->avctx->width ||
217  frame_x + frame_width > s->avctx->width) {
219  "Invalid horizontal range %d-%d\n",
220  frame_x, frame_width);
221  return AVERROR_INVALIDDATA;
222  }
223  if (frame_y < 0 || frame_height < 0 ||
224  frame_y >= s->avctx->height ||
225  frame_height > s->avctx->height ||
226  frame_y + frame_height > s->avctx->height) {
228  "Invalid vertical range %d-%d\n",
229  frame_x, frame_width);
230  return AVERROR_INVALIDDATA;
231  }
232 
233  /* if only a certain region will be updated, copy the entire previous
234  * frame before the decode */
235  if (s->prev_frame->data[0] &&
236  (frame_x || frame_y || (frame_width != s->avctx->width) ||
237  (frame_height != s->avctx->height))) {
238 
239  memcpy(frame->data[0], s->prev_frame->data[0],
240  s->avctx->height * frame->linesize[0]);
241  }
242 
243  /* check if there is a new palette */
244  bytestream2_init(&gb, s->buf + 16, s->size - 16);
245  if (s->buf[15] & 0x02) {
246  bytestream2_skip(&gb, 2);
247  palette32 = (unsigned int *)s->palette;
249  for (i = 0; i < PALETTE_COUNT; i++) {
250  r = bytestream2_get_byteu(&gb) * 4;
251  g = bytestream2_get_byteu(&gb) * 4;
252  b = bytestream2_get_byteu(&gb) * 4;
253  palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
254  palette32[i] |= palette32[i] >> 6 & 0x30303;
255  }
256  } else {
257  av_log(s->avctx, AV_LOG_ERROR, "Incomplete palette\n");
258  return AVERROR_INVALIDDATA;
259  }
260  }
261 
262  if (!s->size)
263  return 0;
264 
265  /* originally UnpackFrame in VAG's code */
266  if (bytestream2_get_bytes_left(&gb) < 1)
267  return AVERROR_INVALIDDATA;
268  meth = bytestream2_get_byteu(&gb);
269  if (meth & 0x80) {
270  int size;
271  if (!s->unpack_buffer_size) {
273  "Trying to unpack LZ-compressed frame with no LZ buffer\n");
274  return AVERROR_INVALIDDATA;
275  }
278  if (size < 0)
279  return size;
280  meth &= 0x7F;
281  bytestream2_init(&gb, s->unpack_buffer, size);
282  }
283 
284  dp = &frame->data[0][frame_y * frame->linesize[0] + frame_x];
285  pp = &s->prev_frame->data[0][frame_y * s->prev_frame->linesize[0] + frame_x];
286  switch (meth) {
287  case 1:
288  for (i = 0; i < frame_height; i++) {
289  ofs = 0;
290  do {
291  len = bytestream2_get_byte(&gb);
292  if (len & 0x80) {
293  len = (len & 0x7F) + 1;
294  if (ofs + len > frame_width ||
296  return AVERROR_INVALIDDATA;
297  bytestream2_get_bufferu(&gb, &dp[ofs], len);
298  ofs += len;
299  } else {
300  /* interframe pixel copy */
301  if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
302  return AVERROR_INVALIDDATA;
303  memcpy(&dp[ofs], &pp[ofs], len + 1);
304  ofs += len + 1;
305  }
306  } while (ofs < frame_width);
307  if (ofs > frame_width) {
309  "offset > width (%d > %d)\n",
310  ofs, frame_width);
311  return AVERROR_INVALIDDATA;
312  }
313  dp += frame->linesize[0];
314  pp += s->prev_frame->linesize[0];
315  }
316  break;
317 
318  case 2:
319  for (i = 0; i < frame_height; i++) {
320  bytestream2_get_buffer(&gb, dp, frame_width);
321  dp += frame->linesize[0];
322  pp += s->prev_frame->linesize[0];
323  }
324  break;
325 
326  case 3:
327  for (i = 0; i < frame_height; i++) {
328  ofs = 0;
329  do {
330  len = bytestream2_get_byte(&gb);
331  if (len & 0x80) {
332  len = (len & 0x7F) + 1;
333  if (bytestream2_peek_byte(&gb) == 0xFF) {
334  int slen = len;
335  bytestream2_get_byte(&gb);
336  len = rle_unpack(gb.buffer, &dp[ofs],
337  len, bytestream2_get_bytes_left(&gb),
338  frame_width - ofs);
339  ofs += slen;
340  bytestream2_skip(&gb, len);
341  } else {
342  bytestream2_get_buffer(&gb, &dp[ofs], len);
343  ofs += len;
344  }
345  } else {
346  /* interframe pixel copy */
347  if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
348  return AVERROR_INVALIDDATA;
349  memcpy(&dp[ofs], &pp[ofs], len + 1);
350  ofs += len + 1;
351  }
352  } while (ofs < frame_width);
353  if (ofs > frame_width) {
355  "offset > width (%d > %d)\n",
356  ofs, frame_width);
357  return AVERROR_INVALIDDATA;
358  }
359  dp += frame->linesize[0];
360  pp += s->prev_frame->linesize[0];
361  }
362  break;
363  }
364  return 0;
365 }
366 
368 {
369  VmdVideoContext *s = avctx->priv_data;
370 
372  av_freep(&s->unpack_buffer);
373  s->unpack_buffer_size = 0;
374 
375  return 0;
376 }
377 
379 {
380  VmdVideoContext *s = avctx->priv_data;
381  int i;
382  unsigned int *palette32;
383  int palette_index = 0;
384  unsigned char r, g, b;
385  unsigned char *vmd_header;
386  unsigned char *raw_palette;
387 
388  s->avctx = avctx;
389  avctx->pix_fmt = AV_PIX_FMT_PAL8;
390 
391  /* make sure the VMD header made it */
392  if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
393  av_log(s->avctx, AV_LOG_ERROR, "expected extradata size of %d\n",
395  return AVERROR_INVALIDDATA;
396  }
397  vmd_header = (unsigned char *)avctx->extradata;
398 
399  s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
400  if (s->unpack_buffer_size) {
402  if (!s->unpack_buffer)
403  return AVERROR(ENOMEM);
404  }
405 
406  /* load up the initial palette */
407  raw_palette = &vmd_header[28];
408  palette32 = (unsigned int *)s->palette;
409  for (i = 0; i < PALETTE_COUNT; i++) {
410  r = raw_palette[palette_index++] * 4;
411  g = raw_palette[palette_index++] * 4;
412  b = raw_palette[palette_index++] * 4;
413  palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
414  palette32[i] |= palette32[i] >> 6 & 0x30303;
415  }
416 
417  s->prev_frame = av_frame_alloc();
418  if (!s->prev_frame) {
419  vmdvideo_decode_end(avctx);
420  return AVERROR(ENOMEM);
421  }
422 
423  return 0;
424 }
425 
427  void *data, int *got_frame,
428  AVPacket *avpkt)
429 {
430  const uint8_t *buf = avpkt->data;
431  int buf_size = avpkt->size;
432  VmdVideoContext *s = avctx->priv_data;
433  AVFrame *frame = data;
434  int ret;
435 
436  s->buf = buf;
437  s->size = buf_size;
438 
439  if (buf_size < 16)
440  return AVERROR_INVALIDDATA;
441 
442  if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
443  return ret;
444 
445  if ((ret = vmd_decode(s, frame)) < 0)
446  return ret;
447 
448  /* make the palette available on the way out */
449  memcpy(frame->data[1], s->palette, PALETTE_COUNT * 4);
450 
451  /* shuffle frames */
453  if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
454  return ret;
455 
456  *got_frame = 1;
457 
458  /* report that the buffer was completely consumed */
459  return buf_size;
460 }
461 
463  .name = "vmdvideo",
464  .long_name = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
465  .type = AVMEDIA_TYPE_VIDEO,
466  .id = AV_CODEC_ID_VMDVIDEO,
467  .priv_data_size = sizeof(VmdVideoContext),
471  .capabilities = CODEC_CAP_DR1,
472 };