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svq1dec.c
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1 /*
2  * SVQ1 decoder
3  * ported to MPlayer by Arpi <arpi@thot.banki.hu>
4  * ported to libavcodec by Nick Kurshev <nickols_k@mail.ru>
5  *
6  * Copyright (c) 2002 The Xine Project
7  * Copyright (c) 2002 The FFmpeg Project
8  *
9  * SVQ1 Encoder (c) 2004 Mike Melanson <melanson@pcisys.net>
10  *
11  * This file is part of FFmpeg.
12  *
13  * FFmpeg is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU Lesser General Public
15  * License as published by the Free Software Foundation; either
16  * version 2.1 of the License, or (at your option) any later version.
17  *
18  * FFmpeg is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21  * Lesser General Public License for more details.
22  *
23  * You should have received a copy of the GNU Lesser General Public
24  * License along with FFmpeg; if not, write to the Free Software
25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26  */
27 
28 /**
29  * @file
30  * Sorenson Vector Quantizer #1 (SVQ1) video codec.
31  * For more information of the SVQ1 algorithm, visit:
32  * http://www.pcisys.net/~melanson/codecs/
33  */
34 
35 #include "avcodec.h"
36 #include "get_bits.h"
37 #include "h263.h"
38 #include "hpeldsp.h"
39 #include "internal.h"
40 #include "mathops.h"
41 #include "svq1.h"
42 
43 static VLC svq1_block_type;
44 static VLC svq1_motion_component;
45 static VLC svq1_intra_multistage[6];
46 static VLC svq1_inter_multistage[6];
47 static VLC svq1_intra_mean;
48 static VLC svq1_inter_mean;
49 
50 /* motion vector (prediction) */
51 typedef struct svq1_pmv_s {
52  int x;
53  int y;
54 } svq1_pmv;
55 
56 typedef struct SVQ1Context {
57  HpelDSPContext hdsp;
58  GetBitContext gb;
59  AVFrame *prev;
60 
61  uint8_t *pkt_swapped;
62  int pkt_swapped_allocated;
63 
64  int width;
65  int height;
66  int frame_code;
67  int nonref; // 1 if the current frame won't be referenced
68 } SVQ1Context;
69 
70 static const uint8_t string_table[256] = {
71  0x00, 0xD5, 0x7F, 0xAA, 0xFE, 0x2B, 0x81, 0x54,
72  0x29, 0xFC, 0x56, 0x83, 0xD7, 0x02, 0xA8, 0x7D,
73  0x52, 0x87, 0x2D, 0xF8, 0xAC, 0x79, 0xD3, 0x06,
74  0x7B, 0xAE, 0x04, 0xD1, 0x85, 0x50, 0xFA, 0x2F,
75  0xA4, 0x71, 0xDB, 0x0E, 0x5A, 0x8F, 0x25, 0xF0,
76  0x8D, 0x58, 0xF2, 0x27, 0x73, 0xA6, 0x0C, 0xD9,
77  0xF6, 0x23, 0x89, 0x5C, 0x08, 0xDD, 0x77, 0xA2,
78  0xDF, 0x0A, 0xA0, 0x75, 0x21, 0xF4, 0x5E, 0x8B,
79  0x9D, 0x48, 0xE2, 0x37, 0x63, 0xB6, 0x1C, 0xC9,
80  0xB4, 0x61, 0xCB, 0x1E, 0x4A, 0x9F, 0x35, 0xE0,
81  0xCF, 0x1A, 0xB0, 0x65, 0x31, 0xE4, 0x4E, 0x9B,
82  0xE6, 0x33, 0x99, 0x4C, 0x18, 0xCD, 0x67, 0xB2,
83  0x39, 0xEC, 0x46, 0x93, 0xC7, 0x12, 0xB8, 0x6D,
84  0x10, 0xC5, 0x6F, 0xBA, 0xEE, 0x3B, 0x91, 0x44,
85  0x6B, 0xBE, 0x14, 0xC1, 0x95, 0x40, 0xEA, 0x3F,
86  0x42, 0x97, 0x3D, 0xE8, 0xBC, 0x69, 0xC3, 0x16,
87  0xEF, 0x3A, 0x90, 0x45, 0x11, 0xC4, 0x6E, 0xBB,
88  0xC6, 0x13, 0xB9, 0x6C, 0x38, 0xED, 0x47, 0x92,
89  0xBD, 0x68, 0xC2, 0x17, 0x43, 0x96, 0x3C, 0xE9,
90  0x94, 0x41, 0xEB, 0x3E, 0x6A, 0xBF, 0x15, 0xC0,
91  0x4B, 0x9E, 0x34, 0xE1, 0xB5, 0x60, 0xCA, 0x1F,
92  0x62, 0xB7, 0x1D, 0xC8, 0x9C, 0x49, 0xE3, 0x36,
93  0x19, 0xCC, 0x66, 0xB3, 0xE7, 0x32, 0x98, 0x4D,
94  0x30, 0xE5, 0x4F, 0x9A, 0xCE, 0x1B, 0xB1, 0x64,
95  0x72, 0xA7, 0x0D, 0xD8, 0x8C, 0x59, 0xF3, 0x26,
96  0x5B, 0x8E, 0x24, 0xF1, 0xA5, 0x70, 0xDA, 0x0F,
97  0x20, 0xF5, 0x5F, 0x8A, 0xDE, 0x0B, 0xA1, 0x74,
98  0x09, 0xDC, 0x76, 0xA3, 0xF7, 0x22, 0x88, 0x5D,
99  0xD6, 0x03, 0xA9, 0x7C, 0x28, 0xFD, 0x57, 0x82,
100  0xFF, 0x2A, 0x80, 0x55, 0x01, 0xD4, 0x7E, 0xAB,
101  0x84, 0x51, 0xFB, 0x2E, 0x7A, 0xAF, 0x05, 0xD0,
102  0xAD, 0x78, 0xD2, 0x07, 0x53, 0x86, 0x2C, 0xF9
103 };
104 
105 #define SVQ1_PROCESS_VECTOR() \
106  for (; level > 0; i++) { \
107  /* process next depth */ \
108  if (i == m) { \
109  m = n; \
110  if (--level == 0) \
111  break; \
112  } \
113  /* divide block if next bit set */ \
114  if (!get_bits1(bitbuf)) \
115  break; \
116  /* add child nodes */ \
117  list[n++] = list[i]; \
118  list[n++] = list[i] + (((level & 1) ? pitch : 1) << ((level >> 1) + 1));\
119  }
120 
121 #define SVQ1_ADD_CODEBOOK() \
122  /* add codebook entries to vector */ \
123  for (j = 0; j < stages; j++) { \
124  n3 = codebook[entries[j]] ^ 0x80808080; \
125  n1 += (n3 & 0xFF00FF00) >> 8; \
126  n2 += n3 & 0x00FF00FF; \
127  } \
128  \
129  /* clip to [0..255] */ \
130  if (n1 & 0xFF00FF00) { \
131  n3 = (n1 >> 15 & 0x00010001 | 0x01000100) - 0x00010001; \
132  n1 += 0x7F007F00; \
133  n1 |= (~n1 >> 15 & 0x00010001 | 0x01000100) - 0x00010001; \
134  n1 &= n3 & 0x00FF00FF; \
135  } \
136  \
137  if (n2 & 0xFF00FF00) { \
138  n3 = (n2 >> 15 & 0x00010001 | 0x01000100) - 0x00010001; \
139  n2 += 0x7F007F00; \
140  n2 |= (~n2 >> 15 & 0x00010001 | 0x01000100) - 0x00010001; \
141  n2 &= n3 & 0x00FF00FF; \
142  }
143 
144 #define SVQ1_CALC_CODEBOOK_ENTRIES(cbook) \
145  codebook = (const uint32_t *)cbook[level]; \
146  if (stages > 0) \
147  bit_cache = get_bits(bitbuf, 4 * stages); \
148  /* calculate codebook entries for this vector */ \
149  for (j = 0; j < stages; j++) { \
150  entries[j] = (((bit_cache >> (4 * (stages - j - 1))) & 0xF) + \
151  16 * j) << (level + 1); \
152  } \
153  mean -= stages * 128; \
154  n4 = (mean << 16) + mean;
155 
156 static int svq1_decode_block_intra(GetBitContext *bitbuf, uint8_t *pixels,
157  int pitch)
158 {
159  uint32_t bit_cache;
160  uint8_t *list[63];
161  uint32_t *dst;
162  const uint32_t *codebook;
163  int entries[6];
164  int i, j, m, n;
165  int mean, stages;
166  unsigned x, y, width, height, level;
167  uint32_t n1, n2, n3, n4;
168 
169  /* initialize list for breadth first processing of vectors */
170  list[0] = pixels;
171 
172  /* recursively process vector */
173  for (i = 0, m = 1, n = 1, level = 5; i < n; i++) {
174  SVQ1_PROCESS_VECTOR();
175 
176  /* destination address and vector size */
177  dst = (uint32_t *)list[i];
178  width = 1 << ((4 + level) / 2);
179  height = 1 << ((3 + level) / 2);
180 
181  /* get number of stages (-1 skips vector, 0 for mean only) */
182  stages = get_vlc2(bitbuf, svq1_intra_multistage[level].table, 3, 3) - 1;
183 
184  if (stages == -1) {
185  for (y = 0; y < height; y++)
186  memset(&dst[y * (pitch / 4)], 0, width);
187  continue; /* skip vector */
188  }
189 
190  if ((stages > 0 && level >= 4)) {
191  av_dlog(NULL,
192  "Error (svq1_decode_block_intra): invalid vector: stages=%i level=%i\n",
193  stages, level);
194  return AVERROR_INVALIDDATA; /* invalid vector */
195  }
196  av_assert0(stages >= 0);
197 
198  mean = get_vlc2(bitbuf, svq1_intra_mean.table, 8, 3);
199 
200  if (stages == 0) {
201  for (y = 0; y < height; y++)
202  memset(&dst[y * (pitch / 4)], mean, width);
203  } else {
204  SVQ1_CALC_CODEBOOK_ENTRIES(ff_svq1_intra_codebooks);
205 
206  for (y = 0; y < height; y++) {
207  for (x = 0; x < width / 4; x++, codebook++) {
208  n1 = n4;
209  n2 = n4;
210  SVQ1_ADD_CODEBOOK()
211  /* store result */
212  dst[x] = n1 << 8 | n2;
213  }
214  dst += pitch / 4;
215  }
216  }
217  }
218 
219  return 0;
220 }
221 
222 static int svq1_decode_block_non_intra(GetBitContext *bitbuf, uint8_t *pixels,
223  int pitch)
224 {
225  uint32_t bit_cache;
226  uint8_t *list[63];
227  uint32_t *dst;
228  const uint32_t *codebook;
229  int entries[6];
230  int i, j, m, n;
231  int mean, stages;
232  int x, y, width, height, level;
233  uint32_t n1, n2, n3, n4;
234 
235  /* initialize list for breadth first processing of vectors */
236  list[0] = pixels;
237 
238  /* recursively process vector */
239  for (i = 0, m = 1, n = 1, level = 5; i < n; i++) {
240  SVQ1_PROCESS_VECTOR();
241 
242  /* destination address and vector size */
243  dst = (uint32_t *)list[i];
244  width = 1 << ((4 + level) / 2);
245  height = 1 << ((3 + level) / 2);
246 
247  /* get number of stages (-1 skips vector, 0 for mean only) */
248  stages = get_vlc2(bitbuf, svq1_inter_multistage[level].table, 3, 2) - 1;
249 
250  if (stages == -1)
251  continue; /* skip vector */
252 
253  if ((stages > 0 && level >= 4)) {
254  av_dlog(NULL,
255  "Error (svq1_decode_block_non_intra): invalid vector: stages=%i level=%i\n",
256  stages, level);
257  return AVERROR_INVALIDDATA; /* invalid vector */
258  }
259  av_assert0(stages >= 0);
260 
261  mean = get_vlc2(bitbuf, svq1_inter_mean.table, 9, 3) - 256;
262 
263  SVQ1_CALC_CODEBOOK_ENTRIES(ff_svq1_inter_codebooks);
264 
265  for (y = 0; y < height; y++) {
266  for (x = 0; x < width / 4; x++, codebook++) {
267  n3 = dst[x];
268  /* add mean value to vector */
269  n1 = n4 + ((n3 & 0xFF00FF00) >> 8);
270  n2 = n4 + (n3 & 0x00FF00FF);
271  SVQ1_ADD_CODEBOOK()
272  /* store result */
273  dst[x] = n1 << 8 | n2;
274  }
275  dst += pitch / 4;
276  }
277  }
278  return 0;
279 }
280 
281 static int svq1_decode_motion_vector(GetBitContext *bitbuf, svq1_pmv *mv,
282  svq1_pmv **pmv)
283 {
284  int diff;
285  int i;
286 
287  for (i = 0; i < 2; i++) {
288  /* get motion code */
289  diff = get_vlc2(bitbuf, svq1_motion_component.table, 7, 2);
290  if (diff < 0)
291  return AVERROR_INVALIDDATA;
292  else if (diff) {
293  if (get_bits1(bitbuf))
294  diff = -diff;
295  }
296 
297  /* add median of motion vector predictors and clip result */
298  if (i == 1)
299  mv->y = sign_extend(diff + mid_pred(pmv[0]->y, pmv[1]->y, pmv[2]->y), 6);
300  else
301  mv->x = sign_extend(diff + mid_pred(pmv[0]->x, pmv[1]->x, pmv[2]->x), 6);
302  }
303 
304  return 0;
305 }
306 
307 static void svq1_skip_block(uint8_t *current, uint8_t *previous,
308  int pitch, int x, int y)
309 {
310  uint8_t *src;
311  uint8_t *dst;
312  int i;
313 
314  src = &previous[x + y * pitch];
315  dst = current;
316 
317  for (i = 0; i < 16; i++) {
318  memcpy(dst, src, 16);
319  src += pitch;
320  dst += pitch;
321  }
322 }
323 
324 static int svq1_motion_inter_block(HpelDSPContext *hdsp, GetBitContext *bitbuf,
325  uint8_t *current, uint8_t *previous,
326  int pitch, svq1_pmv *motion, int x, int y,
327  int width, int height)
328 {
329  uint8_t *src;
330  uint8_t *dst;
331  svq1_pmv mv;
332  svq1_pmv *pmv[3];
333  int result;
334 
335  /* predict and decode motion vector */
336  pmv[0] = &motion[0];
337  if (y == 0) {
338  pmv[1] =
339  pmv[2] = pmv[0];
340  } else {
341  pmv[1] = &motion[x / 8 + 2];
342  pmv[2] = &motion[x / 8 + 4];
343  }
344 
345  result = svq1_decode_motion_vector(bitbuf, &mv, pmv);
346  if (result)
347  return result;
348 
349  motion[0].x =
350  motion[x / 8 + 2].x =
351  motion[x / 8 + 3].x = mv.x;
352  motion[0].y =
353  motion[x / 8 + 2].y =
354  motion[x / 8 + 3].y = mv.y;
355 
356  mv.x = av_clip(mv.x, -2 * x, 2 * (width - x - 16));
357  mv.y = av_clip(mv.y, -2 * y, 2 * (height - y - 16));
358 
359  src = &previous[(x + (mv.x >> 1)) + (y + (mv.y >> 1)) * pitch];
360  dst = current;
361 
362  hdsp->put_pixels_tab[0][(mv.y & 1) << 1 | (mv.x & 1)](dst, src, pitch, 16);
363 
364  return 0;
365 }
366 
367 static int svq1_motion_inter_4v_block(HpelDSPContext *hdsp, GetBitContext *bitbuf,
368  uint8_t *current, uint8_t *previous,
369  int pitch, svq1_pmv *motion, int x, int y,
370  int width, int height)
371 {
372  uint8_t *src;
373  uint8_t *dst;
374  svq1_pmv mv;
375  svq1_pmv *pmv[4];
376  int i, result;
377 
378  /* predict and decode motion vector (0) */
379  pmv[0] = &motion[0];
380  if (y == 0) {
381  pmv[1] =
382  pmv[2] = pmv[0];
383  } else {
384  pmv[1] = &motion[(x / 8) + 2];
385  pmv[2] = &motion[(x / 8) + 4];
386  }
387 
388  result = svq1_decode_motion_vector(bitbuf, &mv, pmv);
389  if (result)
390  return result;
391 
392  /* predict and decode motion vector (1) */
393  pmv[0] = &mv;
394  if (y == 0) {
395  pmv[1] =
396  pmv[2] = pmv[0];
397  } else {
398  pmv[1] = &motion[(x / 8) + 3];
399  }
400  result = svq1_decode_motion_vector(bitbuf, &motion[0], pmv);
401  if (result)
402  return result;
403 
404  /* predict and decode motion vector (2) */
405  pmv[1] = &motion[0];
406  pmv[2] = &motion[(x / 8) + 1];
407 
408  result = svq1_decode_motion_vector(bitbuf, &motion[(x / 8) + 2], pmv);
409  if (result)
410  return result;
411 
412  /* predict and decode motion vector (3) */
413  pmv[2] = &motion[(x / 8) + 2];
414  pmv[3] = &motion[(x / 8) + 3];
415 
416  result = svq1_decode_motion_vector(bitbuf, pmv[3], pmv);
417  if (result)
418  return result;
419 
420  /* form predictions */
421  for (i = 0; i < 4; i++) {
422  int mvx = pmv[i]->x + (i & 1) * 16;
423  int mvy = pmv[i]->y + (i >> 1) * 16;
424 
425  // FIXME: clipping or padding?
426  mvx = av_clip(mvx, -2 * x, 2 * (width - x - 8));
427  mvy = av_clip(mvy, -2 * y, 2 * (height - y - 8));
428 
429  src = &previous[(x + (mvx >> 1)) + (y + (mvy >> 1)) * pitch];
430  dst = current;
431 
432  hdsp->put_pixels_tab[1][((mvy & 1) << 1) | (mvx & 1)](dst, src, pitch, 8);
433 
434  /* select next block */
435  if (i & 1)
436  current += 8 * (pitch - 1);
437  else
438  current += 8;
439  }
440 
441  return 0;
442 }
443 
444 static int svq1_decode_delta_block(AVCodecContext *avctx, HpelDSPContext *hdsp,
445  GetBitContext *bitbuf,
446  uint8_t *current, uint8_t *previous,
447  int pitch, svq1_pmv *motion, int x, int y,
448  int width, int height)
449 {
450  uint32_t block_type;
451  int result = 0;
452 
453  /* get block type */
454  block_type = get_vlc2(bitbuf, svq1_block_type.table, 2, 2);
455 
456  /* reset motion vectors */
457  if (block_type == SVQ1_BLOCK_SKIP || block_type == SVQ1_BLOCK_INTRA) {
458  motion[0].x =
459  motion[0].y =
460  motion[x / 8 + 2].x =
461  motion[x / 8 + 2].y =
462  motion[x / 8 + 3].x =
463  motion[x / 8 + 3].y = 0;
464  }
465 
466  switch (block_type) {
467  case SVQ1_BLOCK_SKIP:
468  svq1_skip_block(current, previous, pitch, x, y);
469  break;
470 
471  case SVQ1_BLOCK_INTER:
472  result = svq1_motion_inter_block(hdsp, bitbuf, current, previous,
473  pitch, motion, x, y, width, height);
474 
475  if (result != 0) {
476  av_dlog(avctx, "Error in svq1_motion_inter_block %i\n", result);
477  break;
478  }
479  result = svq1_decode_block_non_intra(bitbuf, current, pitch);
480  break;
481 
482  case SVQ1_BLOCK_INTER_4V:
483  result = svq1_motion_inter_4v_block(hdsp, bitbuf, current, previous,
484  pitch, motion, x, y, width, height);
485 
486  if (result != 0) {
487  av_dlog(avctx, "Error in svq1_motion_inter_4v_block %i\n", result);
488  break;
489  }
490  result = svq1_decode_block_non_intra(bitbuf, current, pitch);
491  break;
492 
493  case SVQ1_BLOCK_INTRA:
494  result = svq1_decode_block_intra(bitbuf, current, pitch);
495  break;
496  }
497 
498  return result;
499 }
500 
501 static void svq1_parse_string(GetBitContext *bitbuf, uint8_t out[257])
502 {
503  uint8_t seed;
504  int i;
505 
506  out[0] = get_bits(bitbuf, 8);
507  seed = string_table[out[0]];
508 
509  for (i = 1; i <= out[0]; i++) {
510  out[i] = get_bits(bitbuf, 8) ^ seed;
511  seed = string_table[out[i] ^ seed];
512  }
513  out[i] = 0;
514 }
515 
516 static int svq1_decode_frame_header(AVCodecContext *avctx, AVFrame *frame)
517 {
518  SVQ1Context *s = avctx->priv_data;
519  GetBitContext *bitbuf = &s->gb;
520  int frame_size_code;
521  int width = s->width;
522  int height = s->height;
523 
524  skip_bits(bitbuf, 8); /* temporal_reference */
525 
526  /* frame type */
527  s->nonref = 0;
528  switch (get_bits(bitbuf, 2)) {
529  case 0:
530  frame->pict_type = AV_PICTURE_TYPE_I;
531  break;
532  case 2:
533  s->nonref = 1;
534  case 1:
535  frame->pict_type = AV_PICTURE_TYPE_P;
536  break;
537  default:
538  av_log(avctx, AV_LOG_ERROR, "Invalid frame type.\n");
539  return AVERROR_INVALIDDATA;
540  }
541 
542  if (frame->pict_type == AV_PICTURE_TYPE_I) {
543  /* unknown fields */
544  if (s->frame_code == 0x50 || s->frame_code == 0x60) {
545  int csum = get_bits(bitbuf, 16);
546 
547  csum = ff_svq1_packet_checksum(bitbuf->buffer,
548  bitbuf->size_in_bits >> 3,
549  csum);
550 
551  av_dlog(avctx, "%s checksum (%02x) for packet data\n",
552  (csum == 0) ? "correct" : "incorrect", csum);
553  }
554 
555  if ((s->frame_code ^ 0x10) >= 0x50) {
556  uint8_t msg[257];
557 
558  svq1_parse_string(bitbuf, msg);
559 
560  av_log(avctx, AV_LOG_INFO,
561  "embedded message:\n%s\n", ((char *)msg) + 1);
562  }
563 
564  skip_bits(bitbuf, 2);
565  skip_bits(bitbuf, 2);
566  skip_bits1(bitbuf);
567 
568  /* load frame size */
569  frame_size_code = get_bits(bitbuf, 3);
570 
571  if (frame_size_code == 7) {
572  /* load width, height (12 bits each) */
573  width = get_bits(bitbuf, 12);
574  height = get_bits(bitbuf, 12);
575 
576  if (!width || !height)
577  return AVERROR_INVALIDDATA;
578  } else {
579  /* get width, height from table */
580  width = ff_svq1_frame_size_table[frame_size_code][0];
581  height = ff_svq1_frame_size_table[frame_size_code][1];
582  }
583  }
584 
585  /* unknown fields */
586  if (get_bits1(bitbuf)) {
587  skip_bits1(bitbuf); /* use packet checksum if (1) */
588  skip_bits1(bitbuf); /* component checksums after image data if (1) */
589 
590  if (get_bits(bitbuf, 2) != 0)
591  return AVERROR_INVALIDDATA;
592  }
593 
594  if (get_bits1(bitbuf)) {
595  skip_bits1(bitbuf);
596  skip_bits(bitbuf, 4);
597  skip_bits1(bitbuf);
598  skip_bits(bitbuf, 2);
599 
600  if (skip_1stop_8data_bits(bitbuf) < 0)
601  return AVERROR_INVALIDDATA;
602  }
603 
604  s->width = width;
605  s->height = height;
606  return 0;
607 }
608 
609 static int svq1_decode_frame(AVCodecContext *avctx, void *data,
610  int *got_frame, AVPacket *avpkt)
611 {
612  const uint8_t *buf = avpkt->data;
613  int buf_size = avpkt->size;
614  SVQ1Context *s = avctx->priv_data;
615  AVFrame *cur = data;
616  uint8_t *current;
617  int result, i, x, y, width, height;
618  svq1_pmv *pmv;
619 
620  /* initialize bit buffer */
621  init_get_bits8(&s->gb, buf, buf_size);
622 
623  /* decode frame header */
624  s->frame_code = get_bits(&s->gb, 22);
625 
626  if ((s->frame_code & ~0x70) || !(s->frame_code & 0x60))
627  return AVERROR_INVALIDDATA;
628 
629  /* swap some header bytes (why?) */
630  if (s->frame_code != 0x20) {
631  uint32_t *src;
632 
633  if (buf_size < 9 * 4) {
634  av_log(avctx, AV_LOG_ERROR, "Input packet too small\n");
635  return AVERROR_INVALIDDATA;
636  }
637 
638  av_fast_padded_malloc(&s->pkt_swapped,
639  &s->pkt_swapped_allocated,
640  buf_size);
641  if (!s->pkt_swapped)
642  return AVERROR(ENOMEM);
643 
644  memcpy(s->pkt_swapped, buf, buf_size);
645  buf = s->pkt_swapped;
646  init_get_bits(&s->gb, buf, buf_size * 8);
647  skip_bits(&s->gb, 22);
648 
649  src = (uint32_t *)(s->pkt_swapped + 4);
650 
651  if (buf_size < 36)
652  return AVERROR_INVALIDDATA;
653 
654  for (i = 0; i < 4; i++)
655  src[i] = ((src[i] << 16) | (src[i] >> 16)) ^ src[7 - i];
656  }
657 
658  result = svq1_decode_frame_header(avctx, cur);
659  if (result != 0) {
660  av_dlog(avctx, "Error in svq1_decode_frame_header %i\n", result);
661  return result;
662  }
663 
664  result = ff_set_dimensions(avctx, s->width, s->height);
665  if (result < 0)
666  return result;
667 
668  if ((avctx->skip_frame >= AVDISCARD_NONREF && s->nonref) ||
669  (avctx->skip_frame >= AVDISCARD_NONKEY &&
670  cur->pict_type != AV_PICTURE_TYPE_I) ||
671  avctx->skip_frame >= AVDISCARD_ALL)
672  return buf_size;
673 
674  result = ff_get_buffer(avctx, cur, s->nonref ? 0 : AV_GET_BUFFER_FLAG_REF);
675  if (result < 0)
676  return result;
677 
678  pmv = av_malloc((FFALIGN(s->width, 16) / 8 + 3) * sizeof(*pmv));
679  if (!pmv)
680  return AVERROR(ENOMEM);
681 
682  /* decode y, u and v components */
683  for (i = 0; i < 3; i++) {
684  int linesize = cur->linesize[i];
685  if (i == 0) {
686  width = FFALIGN(s->width, 16);
687  height = FFALIGN(s->height, 16);
688  } else {
689  if (avctx->flags & CODEC_FLAG_GRAY)
690  break;
691  width = FFALIGN(s->width / 4, 16);
692  height = FFALIGN(s->height / 4, 16);
693  }
694 
695  current = cur->data[i];
696 
697  if (cur->pict_type == AV_PICTURE_TYPE_I) {
698  /* keyframe */
699  for (y = 0; y < height; y += 16) {
700  for (x = 0; x < width; x += 16) {
701  result = svq1_decode_block_intra(&s->gb, &current[x],
702  linesize);
703  if (result) {
704  av_log(avctx, AV_LOG_ERROR,
705  "Error in svq1_decode_block %i (keyframe)\n",
706  result);
707  goto err;
708  }
709  }
710  current += 16 * linesize;
711  }
712  } else {
713  /* delta frame */
714  uint8_t *previous = s->prev->data[i];
715  if (!previous ||
716  s->prev->width != s->width || s->prev->height != s->height) {
717  av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
718  result = AVERROR_INVALIDDATA;
719  goto err;
720  }
721 
722  memset(pmv, 0, ((width / 8) + 3) * sizeof(svq1_pmv));
723 
724  for (y = 0; y < height; y += 16) {
725  for (x = 0; x < width; x += 16) {
726  result = svq1_decode_delta_block(avctx, &s->hdsp,
727  &s->gb, &current[x],
728  previous, linesize,
729  pmv, x, y, width, height);
730  if (result != 0) {
731  av_dlog(avctx,
732  "Error in svq1_decode_delta_block %i\n",
733  result);
734  goto err;
735  }
736  }
737 
738  pmv[0].x =
739  pmv[0].y = 0;
740 
741  current += 16 * linesize;
742  }
743  }
744  }
745 
746  if (!s->nonref) {
747  av_frame_unref(s->prev);
748  result = av_frame_ref(s->prev, cur);
749  if (result < 0)
750  goto err;
751  }
752 
753  *got_frame = 1;
754  result = buf_size;
755 
756 err:
757  av_free(pmv);
758  return result;
759 }
760 
761 static av_cold int svq1_decode_init(AVCodecContext *avctx)
762 {
763  SVQ1Context *s = avctx->priv_data;
764  int i;
765  int offset = 0;
766 
767  s->prev = av_frame_alloc();
768  if (!s->prev)
769  return AVERROR(ENOMEM);
770 
771  s->width = avctx->width + 3 & ~3;
772  s->height = avctx->height + 3 & ~3;
773  avctx->pix_fmt = AV_PIX_FMT_YUV410P;
774 
775  ff_hpeldsp_init(&s->hdsp, avctx->flags);
776 
777  INIT_VLC_STATIC(&svq1_block_type, 2, 4,
778  &ff_svq1_block_type_vlc[0][1], 2, 1,
779  &ff_svq1_block_type_vlc[0][0], 2, 1, 6);
780 
781  INIT_VLC_STATIC(&svq1_motion_component, 7, 33,
782  &ff_mvtab[0][1], 2, 1,
783  &ff_mvtab[0][0], 2, 1, 176);
784 
785  for (i = 0; i < 6; i++) {
786  static const uint8_t sizes[2][6] = { { 14, 10, 14, 18, 16, 18 },
787  { 10, 10, 14, 14, 14, 16 } };
788  static VLC_TYPE table[168][2];
789  svq1_intra_multistage[i].table = &table[offset];
790  svq1_intra_multistage[i].table_allocated = sizes[0][i];
791  offset += sizes[0][i];
792  init_vlc(&svq1_intra_multistage[i], 3, 8,
793  &ff_svq1_intra_multistage_vlc[i][0][1], 2, 1,
794  &ff_svq1_intra_multistage_vlc[i][0][0], 2, 1,
795  INIT_VLC_USE_NEW_STATIC);
796  svq1_inter_multistage[i].table = &table[offset];
797  svq1_inter_multistage[i].table_allocated = sizes[1][i];
798  offset += sizes[1][i];
799  init_vlc(&svq1_inter_multistage[i], 3, 8,
800  &ff_svq1_inter_multistage_vlc[i][0][1], 2, 1,
801  &ff_svq1_inter_multistage_vlc[i][0][0], 2, 1,
802  INIT_VLC_USE_NEW_STATIC);
803  }
804 
805  INIT_VLC_STATIC(&svq1_intra_mean, 8, 256,
806  &ff_svq1_intra_mean_vlc[0][1], 4, 2,
807  &ff_svq1_intra_mean_vlc[0][0], 4, 2, 632);
808 
809  INIT_VLC_STATIC(&svq1_inter_mean, 9, 512,
810  &ff_svq1_inter_mean_vlc[0][1], 4, 2,
811  &ff_svq1_inter_mean_vlc[0][0], 4, 2, 1434);
812 
813  return 0;
814 }
815 
816 static av_cold int svq1_decode_end(AVCodecContext *avctx)
817 {
818  SVQ1Context *s = avctx->priv_data;
819 
820  av_frame_free(&s->prev);
821  av_freep(&s->pkt_swapped);
822  s->pkt_swapped_allocated = 0;
823 
824  return 0;
825 }
826 
827 static void svq1_flush(AVCodecContext *avctx)
828 {
829  SVQ1Context *s = avctx->priv_data;
830 
831  av_frame_unref(s->prev);
832 }
833 
834 AVCodec ff_svq1_decoder = {
835  .name = "svq1",
836  .long_name = NULL_IF_CONFIG_SMALL("Sorenson Vector Quantizer 1 / Sorenson Video 1 / SVQ1"),
837  .type = AVMEDIA_TYPE_VIDEO,
838  .id = AV_CODEC_ID_SVQ1,
839  .priv_data_size = sizeof(SVQ1Context),
840  .init = svq1_decode_init,
841  .close = svq1_decode_end,
842  .decode = svq1_decode_frame,
843  .capabilities = CODEC_CAP_DR1,
844  .flush = svq1_flush,
845  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV410P,
846  AV_PIX_FMT_NONE },
847 };
Generated on Sun Mar 8 2015 02:35:00 for FFmpeg by   doxygen 1.8.2