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mpeg4videodec.c
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1 /*
2  * MPEG4 decoder.
3  * Copyright (c) 2000,2001 Fabrice Bellard
4  * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #define UNCHECKED_BITSTREAM_READER 1
24 
25 #include "libavutil/opt.h"
26 #include "error_resilience.h"
27 #include "internal.h"
28 #include "mpegvideo.h"
29 #include "mpeg4video.h"
30 #include "h263.h"
31 #include "thread.h"
32 
33 /* The defines below define the number of bits that are read at once for
34  * reading vlc values. Changing these may improve speed and data cache needs
35  * be aware though that decreasing them may need the number of stages that is
36  * passed to get_vlc* to be increased. */
37 #define SPRITE_TRAJ_VLC_BITS 6
38 #define DC_VLC_BITS 9
39 #define MB_TYPE_B_VLC_BITS 4
40 
44 
45 static const int mb_type_b_map[4] = {
50 };
51 
52 /**
53  * Predict the ac.
54  * @param n block index (0-3 are luma, 4-5 are chroma)
55  * @param dir the ac prediction direction
56  */
57 void ff_mpeg4_pred_ac(MpegEncContext *s, int16_t *block, int n, int dir)
58 {
59  int i;
60  int16_t *ac_val, *ac_val1;
61  int8_t *const qscale_table = s->current_picture.qscale_table;
62 
63  /* find prediction */
64  ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
65  ac_val1 = ac_val;
66  if (s->ac_pred) {
67  if (dir == 0) {
68  const int xy = s->mb_x - 1 + s->mb_y * s->mb_stride;
69  /* left prediction */
70  ac_val -= 16;
71 
72  if (s->mb_x == 0 || s->qscale == qscale_table[xy] ||
73  n == 1 || n == 3) {
74  /* same qscale */
75  for (i = 1; i < 8; i++)
76  block[s->dsp.idct_permutation[i << 3]] += ac_val[i];
77  } else {
78  /* different qscale, we must rescale */
79  for (i = 1; i < 8; i++)
80  block[s->dsp.idct_permutation[i << 3]] += ROUNDED_DIV(ac_val[i] * qscale_table[xy], s->qscale);
81  }
82  } else {
83  const int xy = s->mb_x + s->mb_y * s->mb_stride - s->mb_stride;
84  /* top prediction */
85  ac_val -= 16 * s->block_wrap[n];
86 
87  if (s->mb_y == 0 || s->qscale == qscale_table[xy] ||
88  n == 2 || n == 3) {
89  /* same qscale */
90  for (i = 1; i < 8; i++)
91  block[s->dsp.idct_permutation[i]] += ac_val[i + 8];
92  } else {
93  /* different qscale, we must rescale */
94  for (i = 1; i < 8; i++)
95  block[s->dsp.idct_permutation[i]] += ROUNDED_DIV(ac_val[i + 8] * qscale_table[xy], s->qscale);
96  }
97  }
98  }
99  /* left copy */
100  for (i = 1; i < 8; i++)
101  ac_val1[i] = block[s->dsp.idct_permutation[i << 3]];
102 
103  /* top copy */
104  for (i = 1; i < 8; i++)
105  ac_val1[8 + i] = block[s->dsp.idct_permutation[i]];
106 }
107 
108 /**
109  * check if the next stuff is a resync marker or the end.
110  * @return 0 if not
111  */
112 static inline int mpeg4_is_resync(Mpeg4DecContext *ctx)
113 {
114  MpegEncContext *s = &ctx->m;
115  int bits_count = get_bits_count(&s->gb);
116  int v = show_bits(&s->gb, 16);
117 
119  return 0;
120 
121  while (v <= 0xFF) {
122  if (s->pict_type == AV_PICTURE_TYPE_B ||
123  (v >> (8 - s->pict_type) != 1) || s->partitioned_frame)
124  break;
125  skip_bits(&s->gb, 8 + s->pict_type);
126  bits_count += 8 + s->pict_type;
127  v = show_bits(&s->gb, 16);
128  }
129 
130  if (bits_count + 8 >= s->gb.size_in_bits) {
131  v >>= 8;
132  v |= 0x7F >> (7 - (bits_count & 7));
133 
134  if (v == 0x7F)
135  return s->mb_num;
136  } else {
137  if (v == ff_mpeg4_resync_prefix[bits_count & 7]) {
138  int len, mb_num;
139  int mb_num_bits = av_log2(s->mb_num - 1) + 1;
140  GetBitContext gb = s->gb;
141 
142  skip_bits(&s->gb, 1);
143  align_get_bits(&s->gb);
144 
145  for (len = 0; len < 32; len++)
146  if (get_bits1(&s->gb))
147  break;
148 
149  mb_num = get_bits(&s->gb, mb_num_bits);
150  if (!mb_num || mb_num > s->mb_num || get_bits_count(&s->gb)+6 > s->gb.size_in_bits)
151  mb_num= -1;
152 
153  s->gb = gb;
154 
156  return mb_num;
157  }
158  }
159  return 0;
160 }
161 
163 {
164  MpegEncContext *s = &ctx->m;
165  int a = 2 << s->sprite_warping_accuracy;
166  int rho = 3 - s->sprite_warping_accuracy;
167  int r = 16 / a;
168  int alpha = 0;
169  int beta = 0;
170  int w = s->width;
171  int h = s->height;
172  int min_ab, i, w2, h2, w3, h3;
173  int sprite_ref[4][2];
174  int virtual_ref[2][2];
175 
176  // only true for rectangle shapes
177  const int vop_ref[4][2] = { { 0, 0 }, { s->width, 0 },
178  { 0, s->height }, { s->width, s->height } };
179  int d[4][2] = { { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 } };
180 
181  if (w <= 0 || h <= 0)
182  return AVERROR_INVALIDDATA;
183 
184  for (i = 0; i < ctx->num_sprite_warping_points; i++) {
185  int length;
186  int x = 0, y = 0;
187 
188  length = get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
189  if (length)
190  x = get_xbits(gb, length);
191 
192  if (!(ctx->divx_version == 500 && ctx->divx_build == 413))
193  skip_bits1(gb); /* marker bit */
194 
195  length = get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
196  if (length)
197  y = get_xbits(gb, length);
198 
199  skip_bits1(gb); /* marker bit */
200  ctx->sprite_traj[i][0] = d[i][0] = x;
201  ctx->sprite_traj[i][1] = d[i][1] = y;
202  }
203  for (; i < 4; i++)
204  ctx->sprite_traj[i][0] = ctx->sprite_traj[i][1] = 0;
205 
206  while ((1 << alpha) < w)
207  alpha++;
208  while ((1 << beta) < h)
209  beta++; /* typo in the mpeg4 std for the definition of w' and h' */
210  w2 = 1 << alpha;
211  h2 = 1 << beta;
212 
213  // Note, the 4th point isn't used for GMC
214  if (ctx->divx_version == 500 && ctx->divx_build == 413) {
215  sprite_ref[0][0] = a * vop_ref[0][0] + d[0][0];
216  sprite_ref[0][1] = a * vop_ref[0][1] + d[0][1];
217  sprite_ref[1][0] = a * vop_ref[1][0] + d[0][0] + d[1][0];
218  sprite_ref[1][1] = a * vop_ref[1][1] + d[0][1] + d[1][1];
219  sprite_ref[2][0] = a * vop_ref[2][0] + d[0][0] + d[2][0];
220  sprite_ref[2][1] = a * vop_ref[2][1] + d[0][1] + d[2][1];
221  } else {
222  sprite_ref[0][0] = (a >> 1) * (2 * vop_ref[0][0] + d[0][0]);
223  sprite_ref[0][1] = (a >> 1) * (2 * vop_ref[0][1] + d[0][1]);
224  sprite_ref[1][0] = (a >> 1) * (2 * vop_ref[1][0] + d[0][0] + d[1][0]);
225  sprite_ref[1][1] = (a >> 1) * (2 * vop_ref[1][1] + d[0][1] + d[1][1]);
226  sprite_ref[2][0] = (a >> 1) * (2 * vop_ref[2][0] + d[0][0] + d[2][0]);
227  sprite_ref[2][1] = (a >> 1) * (2 * vop_ref[2][1] + d[0][1] + d[2][1]);
228  }
229  /* sprite_ref[3][0] = (a >> 1) * (2 * vop_ref[3][0] + d[0][0] + d[1][0] + d[2][0] + d[3][0]);
230  * sprite_ref[3][1] = (a >> 1) * (2 * vop_ref[3][1] + d[0][1] + d[1][1] + d[2][1] + d[3][1]); */
231 
232  /* this is mostly identical to the mpeg4 std (and is totally unreadable
233  * because of that...). Perhaps it should be reordered to be more readable.
234  * The idea behind this virtual_ref mess is to be able to use shifts later
235  * per pixel instead of divides so the distance between points is converted
236  * from w&h based to w2&h2 based which are of the 2^x form. */
237  virtual_ref[0][0] = 16 * (vop_ref[0][0] + w2) +
238  ROUNDED_DIV(((w - w2) *
239  (r * sprite_ref[0][0] - 16 * vop_ref[0][0]) +
240  w2 * (r * sprite_ref[1][0] - 16 * vop_ref[1][0])), w);
241  virtual_ref[0][1] = 16 * vop_ref[0][1] +
242  ROUNDED_DIV(((w - w2) *
243  (r * sprite_ref[0][1] - 16 * vop_ref[0][1]) +
244  w2 * (r * sprite_ref[1][1] - 16 * vop_ref[1][1])), w);
245  virtual_ref[1][0] = 16 * vop_ref[0][0] +
246  ROUNDED_DIV(((h - h2) * (r * sprite_ref[0][0] - 16 * vop_ref[0][0]) +
247  h2 * (r * sprite_ref[2][0] - 16 * vop_ref[2][0])), h);
248  virtual_ref[1][1] = 16 * (vop_ref[0][1] + h2) +
249  ROUNDED_DIV(((h - h2) * (r * sprite_ref[0][1] - 16 * vop_ref[0][1]) +
250  h2 * (r * sprite_ref[2][1] - 16 * vop_ref[2][1])), h);
251 
252  switch (ctx->num_sprite_warping_points) {
253  case 0:
254  s->sprite_offset[0][0] =
255  s->sprite_offset[0][1] =
256  s->sprite_offset[1][0] =
257  s->sprite_offset[1][1] = 0;
258  s->sprite_delta[0][0] = a;
259  s->sprite_delta[0][1] =
260  s->sprite_delta[1][0] = 0;
261  s->sprite_delta[1][1] = a;
262  ctx->sprite_shift[0] =
263  ctx->sprite_shift[1] = 0;
264  break;
265  case 1: // GMC only
266  s->sprite_offset[0][0] = sprite_ref[0][0] - a * vop_ref[0][0];
267  s->sprite_offset[0][1] = sprite_ref[0][1] - a * vop_ref[0][1];
268  s->sprite_offset[1][0] = ((sprite_ref[0][0] >> 1) | (sprite_ref[0][0] & 1)) -
269  a * (vop_ref[0][0] / 2);
270  s->sprite_offset[1][1] = ((sprite_ref[0][1] >> 1) | (sprite_ref[0][1] & 1)) -
271  a * (vop_ref[0][1] / 2);
272  s->sprite_delta[0][0] = a;
273  s->sprite_delta[0][1] =
274  s->sprite_delta[1][0] = 0;
275  s->sprite_delta[1][1] = a;
276  ctx->sprite_shift[0] =
277  ctx->sprite_shift[1] = 0;
278  break;
279  case 2:
280  s->sprite_offset[0][0] = (sprite_ref[0][0] << (alpha + rho)) +
281  (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
282  (-vop_ref[0][0]) +
283  (r * sprite_ref[0][1] - virtual_ref[0][1]) *
284  (-vop_ref[0][1]) + (1 << (alpha + rho - 1));
285  s->sprite_offset[0][1] = (sprite_ref[0][1] << (alpha + rho)) +
286  (-r * sprite_ref[0][1] + virtual_ref[0][1]) *
287  (-vop_ref[0][0]) +
288  (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
289  (-vop_ref[0][1]) + (1 << (alpha + rho - 1));
290  s->sprite_offset[1][0] = ((-r * sprite_ref[0][0] + virtual_ref[0][0]) *
291  (-2 * vop_ref[0][0] + 1) +
292  (r * sprite_ref[0][1] - virtual_ref[0][1]) *
293  (-2 * vop_ref[0][1] + 1) + 2 * w2 * r *
294  sprite_ref[0][0] - 16 * w2 + (1 << (alpha + rho + 1)));
295  s->sprite_offset[1][1] = ((-r * sprite_ref[0][1] + virtual_ref[0][1]) *
296  (-2 * vop_ref[0][0] + 1) +
297  (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
298  (-2 * vop_ref[0][1] + 1) + 2 * w2 * r *
299  sprite_ref[0][1] - 16 * w2 + (1 << (alpha + rho + 1)));
300  s->sprite_delta[0][0] = (-r * sprite_ref[0][0] + virtual_ref[0][0]);
301  s->sprite_delta[0][1] = (+r * sprite_ref[0][1] - virtual_ref[0][1]);
302  s->sprite_delta[1][0] = (-r * sprite_ref[0][1] + virtual_ref[0][1]);
303  s->sprite_delta[1][1] = (-r * sprite_ref[0][0] + virtual_ref[0][0]);
304 
305  ctx->sprite_shift[0] = alpha + rho;
306  ctx->sprite_shift[1] = alpha + rho + 2;
307  break;
308  case 3:
309  min_ab = FFMIN(alpha, beta);
310  w3 = w2 >> min_ab;
311  h3 = h2 >> min_ab;
312  s->sprite_offset[0][0] = (sprite_ref[0][0] << (alpha + beta + rho - min_ab)) +
313  (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
314  h3 * (-vop_ref[0][0]) +
315  (-r * sprite_ref[0][0] + virtual_ref[1][0]) *
316  w3 * (-vop_ref[0][1]) +
317  (1 << (alpha + beta + rho - min_ab - 1));
318  s->sprite_offset[0][1] = (sprite_ref[0][1] << (alpha + beta + rho - min_ab)) +
319  (-r * sprite_ref[0][1] + virtual_ref[0][1]) *
320  h3 * (-vop_ref[0][0]) +
321  (-r * sprite_ref[0][1] + virtual_ref[1][1]) *
322  w3 * (-vop_ref[0][1]) +
323  (1 << (alpha + beta + rho - min_ab - 1));
324  s->sprite_offset[1][0] = (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
325  h3 * (-2 * vop_ref[0][0] + 1) +
326  (-r * sprite_ref[0][0] + virtual_ref[1][0]) *
327  w3 * (-2 * vop_ref[0][1] + 1) + 2 * w2 * h3 *
328  r * sprite_ref[0][0] - 16 * w2 * h3 +
329  (1 << (alpha + beta + rho - min_ab + 1));
330  s->sprite_offset[1][1] = (-r * sprite_ref[0][1] + virtual_ref[0][1]) *
331  h3 * (-2 * vop_ref[0][0] + 1) +
332  (-r * sprite_ref[0][1] + virtual_ref[1][1]) *
333  w3 * (-2 * vop_ref[0][1] + 1) + 2 * w2 * h3 *
334  r * sprite_ref[0][1] - 16 * w2 * h3 +
335  (1 << (alpha + beta + rho - min_ab + 1));
336  s->sprite_delta[0][0] = (-r * sprite_ref[0][0] + virtual_ref[0][0]) * h3;
337  s->sprite_delta[0][1] = (-r * sprite_ref[0][0] + virtual_ref[1][0]) * w3;
338  s->sprite_delta[1][0] = (-r * sprite_ref[0][1] + virtual_ref[0][1]) * h3;
339  s->sprite_delta[1][1] = (-r * sprite_ref[0][1] + virtual_ref[1][1]) * w3;
340 
341  ctx->sprite_shift[0] = alpha + beta + rho - min_ab;
342  ctx->sprite_shift[1] = alpha + beta + rho - min_ab + 2;
343  break;
344  }
345  /* try to simplify the situation */
346  if (s->sprite_delta[0][0] == a << ctx->sprite_shift[0] &&
347  s->sprite_delta[0][1] == 0 &&
348  s->sprite_delta[1][0] == 0 &&
349  s->sprite_delta[1][1] == a << ctx->sprite_shift[0]) {
350  s->sprite_offset[0][0] >>= ctx->sprite_shift[0];
351  s->sprite_offset[0][1] >>= ctx->sprite_shift[0];
352  s->sprite_offset[1][0] >>= ctx->sprite_shift[1];
353  s->sprite_offset[1][1] >>= ctx->sprite_shift[1];
354  s->sprite_delta[0][0] = a;
355  s->sprite_delta[0][1] = 0;
356  s->sprite_delta[1][0] = 0;
357  s->sprite_delta[1][1] = a;
358  ctx->sprite_shift[0] = 0;
359  ctx->sprite_shift[1] = 0;
361  } else {
362  int shift_y = 16 - ctx->sprite_shift[0];
363  int shift_c = 16 - ctx->sprite_shift[1];
364  for (i = 0; i < 2; i++) {
365  s->sprite_offset[0][i] <<= shift_y;
366  s->sprite_offset[1][i] <<= shift_c;
367  s->sprite_delta[0][i] <<= shift_y;
368  s->sprite_delta[1][i] <<= shift_y;
369  ctx->sprite_shift[i] = 16;
370  }
372  }
373 
374  return 0;
375 }
376 
378  int len = FFMIN(ctx->time_increment_bits + 3, 15);
379 
380  get_bits(gb, len);
381  if (get_bits1(gb))
382  get_bits(gb, len);
383  check_marker(gb, "after new_pred");
384 
385  return 0;
386 }
387 
388 /**
389  * Decode the next video packet.
390  * @return <0 if something went wrong
391  */
393 {
394  MpegEncContext *s = &ctx->m;
395 
396  int mb_num_bits = av_log2(s->mb_num - 1) + 1;
397  int header_extension = 0, mb_num, len;
398 
399  /* is there enough space left for a video packet + header */
400  if (get_bits_count(&s->gb) > s->gb.size_in_bits - 20)
401  return -1;
402 
403  for (len = 0; len < 32; len++)
404  if (get_bits1(&s->gb))
405  break;
406 
408  av_log(s->avctx, AV_LOG_ERROR, "marker does not match f_code\n");
409  return -1;
410  }
411 
412  if (ctx->shape != RECT_SHAPE) {
413  header_extension = get_bits1(&s->gb);
414  // FIXME more stuff here
415  }
416 
417  mb_num = get_bits(&s->gb, mb_num_bits);
418  if (mb_num >= s->mb_num) {
420  "illegal mb_num in video packet (%d %d) \n", mb_num, s->mb_num);
421  return -1;
422  }
423 
424  s->mb_x = mb_num % s->mb_width;
425  s->mb_y = mb_num / s->mb_width;
426 
427  if (ctx->shape != BIN_ONLY_SHAPE) {
428  int qscale = get_bits(&s->gb, s->quant_precision);
429  if (qscale)
430  s->chroma_qscale = s->qscale = qscale;
431  }
432 
433  if (ctx->shape == RECT_SHAPE)
434  header_extension = get_bits1(&s->gb);
435 
436  if (header_extension) {
437  int time_incr = 0;
438 
439  while (get_bits1(&s->gb) != 0)
440  time_incr++;
441 
442  check_marker(&s->gb, "before time_increment in video packed header");
443  skip_bits(&s->gb, ctx->time_increment_bits); /* time_increment */
444  check_marker(&s->gb, "before vop_coding_type in video packed header");
445 
446  skip_bits(&s->gb, 2); /* vop coding type */
447  // FIXME not rect stuff here
448 
449  if (ctx->shape != BIN_ONLY_SHAPE) {
450  skip_bits(&s->gb, 3); /* intra dc vlc threshold */
451  // FIXME don't just ignore everything
452  if (s->pict_type == AV_PICTURE_TYPE_S &&
453  ctx->vol_sprite_usage == GMC_SPRITE) {
454  if (mpeg4_decode_sprite_trajectory(ctx, &s->gb) < 0)
455  return AVERROR_INVALIDDATA;
456  av_log(s->avctx, AV_LOG_ERROR, "untested\n");
457  }
458 
459  // FIXME reduced res stuff here
460 
461  if (s->pict_type != AV_PICTURE_TYPE_I) {
462  int f_code = get_bits(&s->gb, 3); /* fcode_for */
463  if (f_code == 0)
465  "Error, video packet header damaged (f_code=0)\n");
466  }
467  if (s->pict_type == AV_PICTURE_TYPE_B) {
468  int b_code = get_bits(&s->gb, 3);
469  if (b_code == 0)
471  "Error, video packet header damaged (b_code=0)\n");
472  }
473  }
474  }
475  if (ctx->new_pred)
476  decode_new_pred(ctx, &s->gb);
477 
478  return 0;
479 }
480 
481 /**
482  * Get the average motion vector for a GMC MB.
483  * @param n either 0 for the x component or 1 for y
484  * @return the average MV for a GMC MB
485  */
486 static inline int get_amv(Mpeg4DecContext *ctx, int n)
487 {
488  MpegEncContext *s = &ctx->m;
489  int x, y, mb_v, sum, dx, dy, shift;
490  int len = 1 << (s->f_code + 4);
491  const int a = s->sprite_warping_accuracy;
492 
493  if (s->workaround_bugs & FF_BUG_AMV)
494  len >>= s->quarter_sample;
495 
496  if (s->real_sprite_warping_points == 1) {
497  if (ctx->divx_version == 500 && ctx->divx_build == 413)
498  sum = s->sprite_offset[0][n] / (1 << (a - s->quarter_sample));
499  else
500  sum = RSHIFT(s->sprite_offset[0][n] << s->quarter_sample, a);
501  } else {
502  dx = s->sprite_delta[n][0];
503  dy = s->sprite_delta[n][1];
504  shift = ctx->sprite_shift[0];
505  if (n)
506  dy -= 1 << (shift + a + 1);
507  else
508  dx -= 1 << (shift + a + 1);
509  mb_v = s->sprite_offset[0][n] + dx * s->mb_x * 16 + dy * s->mb_y * 16;
510 
511  sum = 0;
512  for (y = 0; y < 16; y++) {
513  int v;
514 
515  v = mb_v + dy * y;
516  // FIXME optimize
517  for (x = 0; x < 16; x++) {
518  sum += v >> shift;
519  v += dx;
520  }
521  }
522  sum = RSHIFT(sum, a + 8 - s->quarter_sample);
523  }
524 
525  if (sum < -len)
526  sum = -len;
527  else if (sum >= len)
528  sum = len - 1;
529 
530  return sum;
531 }
532 
533 /**
534  * Decode the dc value.
535  * @param n block index (0-3 are luma, 4-5 are chroma)
536  * @param dir_ptr the prediction direction will be stored here
537  * @return the quantized dc
538  */
539 static inline int mpeg4_decode_dc(MpegEncContext *s, int n, int *dir_ptr)
540 {
541  int level, code;
542 
543  if (n < 4)
544  code = get_vlc2(&s->gb, dc_lum.table, DC_VLC_BITS, 1);
545  else
546  code = get_vlc2(&s->gb, dc_chrom.table, DC_VLC_BITS, 1);
547 
548  if (code < 0 || code > 9 /* && s->nbit < 9 */) {
549  av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
550  return -1;
551  }
552 
553  if (code == 0) {
554  level = 0;
555  } else {
556  if (IS_3IV1) {
557  if (code == 1)
558  level = 2 * get_bits1(&s->gb) - 1;
559  else {
560  if (get_bits1(&s->gb))
561  level = get_bits(&s->gb, code - 1) + (1 << (code - 1));
562  else
563  level = -get_bits(&s->gb, code - 1) - (1 << (code - 1));
564  }
565  } else {
566  level = get_xbits(&s->gb, code);
567  }
568 
569  if (code > 8) {
570  if (get_bits1(&s->gb) == 0) { /* marker */
572  av_log(s->avctx, AV_LOG_ERROR, "dc marker bit missing\n");
573  return -1;
574  }
575  }
576  }
577  }
578 
579  return ff_mpeg4_pred_dc(s, n, level, dir_ptr, 0);
580 }
581 
582 /**
583  * Decode first partition.
584  * @return number of MBs decoded or <0 if an error occurred
585  */
587 {
588  MpegEncContext *s = &ctx->m;
589  int mb_num = 0;
590  static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
591 
592  /* decode first partition */
593  s->first_slice_line = 1;
594  for (; s->mb_y < s->mb_height; s->mb_y++) {
596  for (; s->mb_x < s->mb_width; s->mb_x++) {
597  const int xy = s->mb_x + s->mb_y * s->mb_stride;
598  int cbpc;
599  int dir = 0;
600 
601  mb_num++;
603  if (s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y + 1)
604  s->first_slice_line = 0;
605 
606  if (s->pict_type == AV_PICTURE_TYPE_I) {
607  int i;
608 
609  do {
610  if (show_bits_long(&s->gb, 19) == DC_MARKER)
611  return mb_num - 1;
612 
614  if (cbpc < 0) {
616  "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
617  return -1;
618  }
619  } while (cbpc == 8);
620 
621  s->cbp_table[xy] = cbpc & 3;
623  s->mb_intra = 1;
624 
625  if (cbpc & 4)
626  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
627 
628  s->current_picture.qscale_table[xy] = s->qscale;
629 
630  s->mbintra_table[xy] = 1;
631  for (i = 0; i < 6; i++) {
632  int dc_pred_dir;
633  int dc = mpeg4_decode_dc(s, i, &dc_pred_dir);
634  if (dc < 0) {
636  "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
637  return -1;
638  }
639  dir <<= 1;
640  if (dc_pred_dir)
641  dir |= 1;
642  }
643  s->pred_dir_table[xy] = dir;
644  } else { /* P/S_TYPE */
645  int mx, my, pred_x, pred_y, bits;
646  int16_t *const mot_val = s->current_picture.motion_val[0][s->block_index[0]];
647  const int stride = s->b8_stride * 2;
648 
649 try_again:
650  bits = show_bits(&s->gb, 17);
651  if (bits == MOTION_MARKER)
652  return mb_num - 1;
653 
654  skip_bits1(&s->gb);
655  if (bits & 0x10000) {
656  /* skip mb */
657  if (s->pict_type == AV_PICTURE_TYPE_S &&
658  ctx->vol_sprite_usage == GMC_SPRITE) {
660  MB_TYPE_16x16 |
661  MB_TYPE_GMC |
662  MB_TYPE_L0;
663  mx = get_amv(ctx, 0);
664  my = get_amv(ctx, 1);
665  } else {
667  MB_TYPE_16x16 |
668  MB_TYPE_L0;
669  mx = my = 0;
670  }
671  mot_val[0] =
672  mot_val[2] =
673  mot_val[0 + stride] =
674  mot_val[2 + stride] = mx;
675  mot_val[1] =
676  mot_val[3] =
677  mot_val[1 + stride] =
678  mot_val[3 + stride] = my;
679 
680  if (s->mbintra_table[xy])
682  continue;
683  }
684 
686  if (cbpc < 0) {
688  "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
689  return -1;
690  }
691  if (cbpc == 20)
692  goto try_again;
693 
694  s->cbp_table[xy] = cbpc & (8 + 3); // 8 is dquant
695 
696  s->mb_intra = ((cbpc & 4) != 0);
697 
698  if (s->mb_intra) {
700  s->mbintra_table[xy] = 1;
701  mot_val[0] =
702  mot_val[2] =
703  mot_val[0 + stride] =
704  mot_val[2 + stride] = 0;
705  mot_val[1] =
706  mot_val[3] =
707  mot_val[1 + stride] =
708  mot_val[3 + stride] = 0;
709  } else {
710  if (s->mbintra_table[xy])
712 
713  if (s->pict_type == AV_PICTURE_TYPE_S &&
714  ctx->vol_sprite_usage == GMC_SPRITE &&
715  (cbpc & 16) == 0)
716  s->mcsel = get_bits1(&s->gb);
717  else
718  s->mcsel = 0;
719 
720  if ((cbpc & 16) == 0) {
721  /* 16x16 motion prediction */
722 
723  ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
724  if (!s->mcsel) {
725  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
726  if (mx >= 0xffff)
727  return -1;
728 
729  my = ff_h263_decode_motion(s, pred_y, s->f_code);
730  if (my >= 0xffff)
731  return -1;
733  MB_TYPE_L0;
734  } else {
735  mx = get_amv(ctx, 0);
736  my = get_amv(ctx, 1);
738  MB_TYPE_GMC |
739  MB_TYPE_L0;
740  }
741 
742  mot_val[0] =
743  mot_val[2] =
744  mot_val[0 + stride] =
745  mot_val[2 + stride] = mx;
746  mot_val[1] =
747  mot_val[3] =
748  mot_val[1 + stride] =
749  mot_val[3 + stride] = my;
750  } else {
751  int i;
753  MB_TYPE_L0;
754  for (i = 0; i < 4; i++) {
755  int16_t *mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
756  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
757  if (mx >= 0xffff)
758  return -1;
759 
760  my = ff_h263_decode_motion(s, pred_y, s->f_code);
761  if (my >= 0xffff)
762  return -1;
763  mot_val[0] = mx;
764  mot_val[1] = my;
765  }
766  }
767  }
768  }
769  }
770  s->mb_x = 0;
771  }
772 
773  return mb_num;
774 }
775 
776 /**
777  * decode second partition.
778  * @return <0 if an error occurred
779  */
780 static int mpeg4_decode_partition_b(MpegEncContext *s, int mb_count)
781 {
782  int mb_num = 0;
783  static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
784 
785  s->mb_x = s->resync_mb_x;
786  s->first_slice_line = 1;
787  for (s->mb_y = s->resync_mb_y; mb_num < mb_count; s->mb_y++) {
789  for (; mb_num < mb_count && s->mb_x < s->mb_width; s->mb_x++) {
790  const int xy = s->mb_x + s->mb_y * s->mb_stride;
791 
792  mb_num++;
794  if (s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y + 1)
795  s->first_slice_line = 0;
796 
797  if (s->pict_type == AV_PICTURE_TYPE_I) {
798  int ac_pred = get_bits1(&s->gb);
799  int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
800  if (cbpy < 0) {
802  "cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
803  return -1;
804  }
805 
806  s->cbp_table[xy] |= cbpy << 2;
807  s->current_picture.mb_type[xy] |= ac_pred * MB_TYPE_ACPRED;
808  } else { /* P || S_TYPE */
809  if (IS_INTRA(s->current_picture.mb_type[xy])) {
810  int i;
811  int dir = 0;
812  int ac_pred = get_bits1(&s->gb);
813  int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
814 
815  if (cbpy < 0) {
817  "I cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
818  return -1;
819  }
820 
821  if (s->cbp_table[xy] & 8)
822  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
823  s->current_picture.qscale_table[xy] = s->qscale;
824 
825  for (i = 0; i < 6; i++) {
826  int dc_pred_dir;
827  int dc = mpeg4_decode_dc(s, i, &dc_pred_dir);
828  if (dc < 0) {
830  "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
831  return -1;
832  }
833  dir <<= 1;
834  if (dc_pred_dir)
835  dir |= 1;
836  }
837  s->cbp_table[xy] &= 3; // remove dquant
838  s->cbp_table[xy] |= cbpy << 2;
839  s->current_picture.mb_type[xy] |= ac_pred * MB_TYPE_ACPRED;
840  s->pred_dir_table[xy] = dir;
841  } else if (IS_SKIP(s->current_picture.mb_type[xy])) {
842  s->current_picture.qscale_table[xy] = s->qscale;
843  s->cbp_table[xy] = 0;
844  } else {
845  int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
846 
847  if (cbpy < 0) {
849  "P cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
850  return -1;
851  }
852 
853  if (s->cbp_table[xy] & 8)
854  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
855  s->current_picture.qscale_table[xy] = s->qscale;
856 
857  s->cbp_table[xy] &= 3; // remove dquant
858  s->cbp_table[xy] |= (cbpy ^ 0xf) << 2;
859  }
860  }
861  }
862  if (mb_num >= mb_count)
863  return 0;
864  s->mb_x = 0;
865  }
866  return 0;
867 }
868 
869 /**
870  * Decode the first and second partition.
871  * @return <0 if error (and sets error type in the error_status_table)
872  */
874 {
875  MpegEncContext *s = &ctx->m;
876  int mb_num;
877  const int part_a_error = s->pict_type == AV_PICTURE_TYPE_I ? (ER_DC_ERROR | ER_MV_ERROR) : ER_MV_ERROR;
878  const int part_a_end = s->pict_type == AV_PICTURE_TYPE_I ? (ER_DC_END | ER_MV_END) : ER_MV_END;
879 
880  mb_num = mpeg4_decode_partition_a(ctx);
881  if (mb_num < 0) {
883  s->mb_x, s->mb_y, part_a_error);
884  return -1;
885  }
886 
887  if (s->resync_mb_x + s->resync_mb_y * s->mb_width + mb_num > s->mb_num) {
888  av_log(s->avctx, AV_LOG_ERROR, "slice below monitor ...\n");
890  s->mb_x, s->mb_y, part_a_error);
891  return -1;
892  }
893 
894  s->mb_num_left = mb_num;
895 
896  if (s->pict_type == AV_PICTURE_TYPE_I) {
897  while (show_bits(&s->gb, 9) == 1)
898  skip_bits(&s->gb, 9);
899  if (get_bits_long(&s->gb, 19) != DC_MARKER) {
901  "marker missing after first I partition at %d %d\n",
902  s->mb_x, s->mb_y);
903  return -1;
904  }
905  } else {
906  while (show_bits(&s->gb, 10) == 1)
907  skip_bits(&s->gb, 10);
908  if (get_bits(&s->gb, 17) != MOTION_MARKER) {
910  "marker missing after first P partition at %d %d\n",
911  s->mb_x, s->mb_y);
912  return -1;
913  }
914  }
916  s->mb_x - 1, s->mb_y, part_a_end);
917 
918  if (mpeg4_decode_partition_b(s, mb_num) < 0) {
919  if (s->pict_type == AV_PICTURE_TYPE_P)
921  s->mb_x, s->mb_y, ER_DC_ERROR);
922  return -1;
923  } else {
924  if (s->pict_type == AV_PICTURE_TYPE_P)
926  s->mb_x - 1, s->mb_y, ER_DC_END);
927  }
928 
929  return 0;
930 }
931 
932 /**
933  * Decode a block.
934  * @return <0 if an error occurred
935  */
936 static inline int mpeg4_decode_block(Mpeg4DecContext *ctx, int16_t *block,
937  int n, int coded, int intra, int rvlc)
938 {
939  MpegEncContext *s = &ctx->m;
940  int level, i, last, run, qmul, qadd;
941  int av_uninit(dc_pred_dir);
942  RLTable *rl;
943  RL_VLC_ELEM *rl_vlc;
944  const uint8_t *scan_table;
945 
946  // Note intra & rvlc should be optimized away if this is inlined
947 
948  if (intra) {
949  if (ctx->use_intra_dc_vlc) {
950  /* DC coef */
951  if (s->partitioned_frame) {
952  level = s->dc_val[0][s->block_index[n]];
953  if (n < 4)
954  level = FASTDIV((level + (s->y_dc_scale >> 1)), s->y_dc_scale);
955  else
956  level = FASTDIV((level + (s->c_dc_scale >> 1)), s->c_dc_scale);
957  dc_pred_dir = (s->pred_dir_table[s->mb_x + s->mb_y * s->mb_stride] << n) & 32;
958  } else {
959  level = mpeg4_decode_dc(s, n, &dc_pred_dir);
960  if (level < 0)
961  return -1;
962  }
963  block[0] = level;
964  i = 0;
965  } else {
966  i = -1;
967  ff_mpeg4_pred_dc(s, n, 0, &dc_pred_dir, 0);
968  }
969  if (!coded)
970  goto not_coded;
971 
972  if (rvlc) {
973  rl = &ff_rvlc_rl_intra;
974  rl_vlc = ff_rvlc_rl_intra.rl_vlc[0];
975  } else {
976  rl = &ff_mpeg4_rl_intra;
977  rl_vlc = ff_mpeg4_rl_intra.rl_vlc[0];
978  }
979  if (s->ac_pred) {
980  if (dc_pred_dir == 0)
981  scan_table = s->intra_v_scantable.permutated; /* left */
982  else
983  scan_table = s->intra_h_scantable.permutated; /* top */
984  } else {
985  scan_table = s->intra_scantable.permutated;
986  }
987  qmul = 1;
988  qadd = 0;
989  } else {
990  i = -1;
991  if (!coded) {
992  s->block_last_index[n] = i;
993  return 0;
994  }
995  if (rvlc)
996  rl = &ff_rvlc_rl_inter;
997  else
998  rl = &ff_h263_rl_inter;
999 
1000  scan_table = s->intra_scantable.permutated;
1001 
1002  if (s->mpeg_quant) {
1003  qmul = 1;
1004  qadd = 0;
1005  if (rvlc)
1006  rl_vlc = ff_rvlc_rl_inter.rl_vlc[0];
1007  else
1008  rl_vlc = ff_h263_rl_inter.rl_vlc[0];
1009  } else {
1010  qmul = s->qscale << 1;
1011  qadd = (s->qscale - 1) | 1;
1012  if (rvlc)
1013  rl_vlc = ff_rvlc_rl_inter.rl_vlc[s->qscale];
1014  else
1015  rl_vlc = ff_h263_rl_inter.rl_vlc[s->qscale];
1016  }
1017  }
1018  {
1019  OPEN_READER(re, &s->gb);
1020  for (;;) {
1021  UPDATE_CACHE(re, &s->gb);
1022  GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
1023  if (level == 0) {
1024  /* escape */
1025  if (rvlc) {
1026  if (SHOW_UBITS(re, &s->gb, 1) == 0) {
1028  "1. marker bit missing in rvlc esc\n");
1029  return -1;
1030  }
1031  SKIP_CACHE(re, &s->gb, 1);
1032 
1033  last = SHOW_UBITS(re, &s->gb, 1);
1034  SKIP_CACHE(re, &s->gb, 1);
1035  run = SHOW_UBITS(re, &s->gb, 6);
1036  SKIP_COUNTER(re, &s->gb, 1 + 1 + 6);
1037  UPDATE_CACHE(re, &s->gb);
1038 
1039  if (SHOW_UBITS(re, &s->gb, 1) == 0) {
1041  "2. marker bit missing in rvlc esc\n");
1042  return -1;
1043  }
1044  SKIP_CACHE(re, &s->gb, 1);
1045 
1046  level = SHOW_UBITS(re, &s->gb, 11);
1047  SKIP_CACHE(re, &s->gb, 11);
1048 
1049  if (SHOW_UBITS(re, &s->gb, 5) != 0x10) {
1050  av_log(s->avctx, AV_LOG_ERROR, "reverse esc missing\n");
1051  return -1;
1052  }
1053  SKIP_CACHE(re, &s->gb, 5);
1054 
1055  level = level * qmul + qadd;
1056  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1057  SKIP_COUNTER(re, &s->gb, 1 + 11 + 5 + 1);
1058 
1059  i += run + 1;
1060  if (last)
1061  i += 192;
1062  } else {
1063  int cache;
1064  cache = GET_CACHE(re, &s->gb);
1065 
1066  if (IS_3IV1)
1067  cache ^= 0xC0000000;
1068 
1069  if (cache & 0x80000000) {
1070  if (cache & 0x40000000) {
1071  /* third escape */
1072  SKIP_CACHE(re, &s->gb, 2);
1073  last = SHOW_UBITS(re, &s->gb, 1);
1074  SKIP_CACHE(re, &s->gb, 1);
1075  run = SHOW_UBITS(re, &s->gb, 6);
1076  SKIP_COUNTER(re, &s->gb, 2 + 1 + 6);
1077  UPDATE_CACHE(re, &s->gb);
1078 
1079  if (IS_3IV1) {
1080  level = SHOW_SBITS(re, &s->gb, 12);
1081  LAST_SKIP_BITS(re, &s->gb, 12);
1082  } else {
1083  if (SHOW_UBITS(re, &s->gb, 1) == 0) {
1085  "1. marker bit missing in 3. esc\n");
1086  return -1;
1087  }
1088  SKIP_CACHE(re, &s->gb, 1);
1089 
1090  level = SHOW_SBITS(re, &s->gb, 12);
1091  SKIP_CACHE(re, &s->gb, 12);
1092 
1093  if (SHOW_UBITS(re, &s->gb, 1) == 0) {
1095  "2. marker bit missing in 3. esc\n");
1096  return -1;
1097  }
1098 
1099  SKIP_COUNTER(re, &s->gb, 1 + 12 + 1);
1100  }
1101 
1102 #if 0
1103  if (s->error_recognition >= FF_ER_COMPLIANT) {
1104  const int abs_level= FFABS(level);
1105  if (abs_level<=MAX_LEVEL && run<=MAX_RUN) {
1106  const int run1= run - rl->max_run[last][abs_level] - 1;
1107  if (abs_level <= rl->max_level[last][run]) {
1108  av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
1109  return -1;
1110  }
1111  if (s->error_recognition > FF_ER_COMPLIANT) {
1112  if (abs_level <= rl->max_level[last][run]*2) {
1113  av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
1114  return -1;
1115  }
1116  if (run1 >= 0 && abs_level <= rl->max_level[last][run1]) {
1117  av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
1118  return -1;
1119  }
1120  }
1121  }
1122  }
1123 #endif
1124  if (level > 0)
1125  level = level * qmul + qadd;
1126  else
1127  level = level * qmul - qadd;
1128 
1129  if ((unsigned)(level + 2048) > 4095) {
1131  if (level > 2560 || level < -2560) {
1133  "|level| overflow in 3. esc, qp=%d\n",
1134  s->qscale);
1135  return -1;
1136  }
1137  }
1138  level = level < 0 ? -2048 : 2047;
1139  }
1140 
1141  i += run + 1;
1142  if (last)
1143  i += 192;
1144  } else {
1145  /* second escape */
1146  SKIP_BITS(re, &s->gb, 2);
1147  GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
1148  i += run + rl->max_run[run >> 7][level / qmul] + 1; // FIXME opt indexing
1149  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1150  LAST_SKIP_BITS(re, &s->gb, 1);
1151  }
1152  } else {
1153  /* first escape */
1154  SKIP_BITS(re, &s->gb, 1);
1155  GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
1156  i += run;
1157  level = level + rl->max_level[run >> 7][(run - 1) & 63] * qmul; // FIXME opt indexing
1158  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1159  LAST_SKIP_BITS(re, &s->gb, 1);
1160  }
1161  }
1162  } else {
1163  i += run;
1164  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1165  LAST_SKIP_BITS(re, &s->gb, 1);
1166  }
1167  if (i > 62) {
1168  i -= 192;
1169  if (i & (~63)) {
1171  "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1172  return -1;
1173  }
1174 
1175  block[scan_table[i]] = level;
1176  break;
1177  }
1178 
1179  block[scan_table[i]] = level;
1180  }
1181  CLOSE_READER(re, &s->gb);
1182  }
1183 
1184 not_coded:
1185  if (intra) {
1186  if (!ctx->use_intra_dc_vlc) {
1187  block[0] = ff_mpeg4_pred_dc(s, n, block[0], &dc_pred_dir, 0);
1188 
1189  i -= i >> 31; // if (i == -1) i = 0;
1190  }
1191 
1192  ff_mpeg4_pred_ac(s, block, n, dc_pred_dir);
1193  if (s->ac_pred)
1194  i = 63; // FIXME not optimal
1195  }
1196  s->block_last_index[n] = i;
1197  return 0;
1198 }
1199 
1200 /**
1201  * decode partition C of one MB.
1202  * @return <0 if an error occurred
1203  */
1205 {
1206  Mpeg4DecContext *ctx = (Mpeg4DecContext *)s;
1207  int cbp, mb_type;
1208  const int xy = s->mb_x + s->mb_y * s->mb_stride;
1209 
1210  mb_type = s->current_picture.mb_type[xy];
1211  cbp = s->cbp_table[xy];
1212 
1213  ctx->use_intra_dc_vlc = s->qscale < ctx->intra_dc_threshold;
1214 
1215  if (s->current_picture.qscale_table[xy] != s->qscale)
1217 
1218  if (s->pict_type == AV_PICTURE_TYPE_P ||
1219  s->pict_type == AV_PICTURE_TYPE_S) {
1220  int i;
1221  for (i = 0; i < 4; i++) {
1222  s->mv[0][i][0] = s->current_picture.motion_val[0][s->block_index[i]][0];
1223  s->mv[0][i][1] = s->current_picture.motion_val[0][s->block_index[i]][1];
1224  }
1225  s->mb_intra = IS_INTRA(mb_type);
1226 
1227  if (IS_SKIP(mb_type)) {
1228  /* skip mb */
1229  for (i = 0; i < 6; i++)
1230  s->block_last_index[i] = -1;
1231  s->mv_dir = MV_DIR_FORWARD;
1232  s->mv_type = MV_TYPE_16X16;
1234  && ctx->vol_sprite_usage == GMC_SPRITE) {
1235  s->mcsel = 1;
1236  s->mb_skipped = 0;
1237  } else {
1238  s->mcsel = 0;
1239  s->mb_skipped = 1;
1240  }
1241  } else if (s->mb_intra) {
1243  } else if (!s->mb_intra) {
1244  // s->mcsel = 0; // FIXME do we need to init that?
1245 
1246  s->mv_dir = MV_DIR_FORWARD;
1247  if (IS_8X8(mb_type)) {
1248  s->mv_type = MV_TYPE_8X8;
1249  } else {
1250  s->mv_type = MV_TYPE_16X16;
1251  }
1252  }
1253  } else { /* I-Frame */
1254  s->mb_intra = 1;
1256  }
1257 
1258  if (!IS_SKIP(mb_type)) {
1259  int i;
1260  s->dsp.clear_blocks(s->block[0]);
1261  /* decode each block */
1262  for (i = 0; i < 6; i++) {
1263  if (mpeg4_decode_block(ctx, block[i], i, cbp & 32, s->mb_intra, ctx->rvlc) < 0) {
1265  "texture corrupted at %d %d %d\n",
1266  s->mb_x, s->mb_y, s->mb_intra);
1267  return -1;
1268  }
1269  cbp += cbp;
1270  }
1271  }
1272 
1273  /* per-MB end of slice check */
1274  if (--s->mb_num_left <= 0) {
1275  if (mpeg4_is_resync(ctx))
1276  return SLICE_END;
1277  else
1278  return SLICE_NOEND;
1279  } else {
1280  if (mpeg4_is_resync(ctx)) {
1281  const int delta = s->mb_x + 1 == s->mb_width ? 2 : 1;
1282  if (s->cbp_table[xy + delta])
1283  return SLICE_END;
1284  }
1285  return SLICE_OK;
1286  }
1287 }
1288 
1289 static int mpeg4_decode_mb(MpegEncContext *s, int16_t block[6][64])
1290 {
1291  Mpeg4DecContext *ctx = (Mpeg4DecContext *)s;
1292  int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
1293  int16_t *mot_val;
1294  static int8_t quant_tab[4] = { -1, -2, 1, 2 };
1295  const int xy = s->mb_x + s->mb_y * s->mb_stride;
1296 
1297  av_assert2(s->h263_pred);
1298 
1299  if (s->pict_type == AV_PICTURE_TYPE_P ||
1300  s->pict_type == AV_PICTURE_TYPE_S) {
1301  do {
1302  if (get_bits1(&s->gb)) {
1303  /* skip mb */
1304  s->mb_intra = 0;
1305  for (i = 0; i < 6; i++)
1306  s->block_last_index[i] = -1;
1307  s->mv_dir = MV_DIR_FORWARD;
1308  s->mv_type = MV_TYPE_16X16;
1309  if (s->pict_type == AV_PICTURE_TYPE_S &&
1310  ctx->vol_sprite_usage == GMC_SPRITE) {
1312  MB_TYPE_GMC |
1313  MB_TYPE_16x16 |
1314  MB_TYPE_L0;
1315  s->mcsel = 1;
1316  s->mv[0][0][0] = get_amv(ctx, 0);
1317  s->mv[0][0][1] = get_amv(ctx, 1);
1318  s->mb_skipped = 0;
1319  } else {
1321  MB_TYPE_16x16 |
1322  MB_TYPE_L0;
1323  s->mcsel = 0;
1324  s->mv[0][0][0] = 0;
1325  s->mv[0][0][1] = 0;
1326  s->mb_skipped = 1;
1327  }
1328  goto end;
1329  }
1331  if (cbpc < 0) {
1333  "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
1334  return -1;
1335  }
1336  } while (cbpc == 20);
1337 
1338  s->dsp.clear_blocks(s->block[0]);
1339  dquant = cbpc & 8;
1340  s->mb_intra = ((cbpc & 4) != 0);
1341  if (s->mb_intra)
1342  goto intra;
1343 
1344  if (s->pict_type == AV_PICTURE_TYPE_S &&
1345  ctx->vol_sprite_usage == GMC_SPRITE && (cbpc & 16) == 0)
1346  s->mcsel = get_bits1(&s->gb);
1347  else
1348  s->mcsel = 0;
1349  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1) ^ 0x0F;
1350 
1351  cbp = (cbpc & 3) | (cbpy << 2);
1352  if (dquant)
1353  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
1354  if ((!s->progressive_sequence) &&
1355  (cbp || (s->workaround_bugs & FF_BUG_XVID_ILACE)))
1356  s->interlaced_dct = get_bits1(&s->gb);
1357 
1358  s->mv_dir = MV_DIR_FORWARD;
1359  if ((cbpc & 16) == 0) {
1360  if (s->mcsel) {
1362  MB_TYPE_16x16 |
1363  MB_TYPE_L0;
1364  /* 16x16 global motion prediction */
1365  s->mv_type = MV_TYPE_16X16;
1366  mx = get_amv(ctx, 0);
1367  my = get_amv(ctx, 1);
1368  s->mv[0][0][0] = mx;
1369  s->mv[0][0][1] = my;
1370  } else if ((!s->progressive_sequence) && get_bits1(&s->gb)) {
1372  MB_TYPE_L0 |
1374  /* 16x8 field motion prediction */
1375  s->mv_type = MV_TYPE_FIELD;
1376 
1377  s->field_select[0][0] = get_bits1(&s->gb);
1378  s->field_select[0][1] = get_bits1(&s->gb);
1379 
1380  ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
1381 
1382  for (i = 0; i < 2; i++) {
1383  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
1384  if (mx >= 0xffff)
1385  return -1;
1386 
1387  my = ff_h263_decode_motion(s, pred_y / 2, s->f_code);
1388  if (my >= 0xffff)
1389  return -1;
1390 
1391  s->mv[0][i][0] = mx;
1392  s->mv[0][i][1] = my;
1393  }
1394  } else {
1396  /* 16x16 motion prediction */
1397  s->mv_type = MV_TYPE_16X16;
1398  ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
1399  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
1400 
1401  if (mx >= 0xffff)
1402  return -1;
1403 
1404  my = ff_h263_decode_motion(s, pred_y, s->f_code);
1405 
1406  if (my >= 0xffff)
1407  return -1;
1408  s->mv[0][0][0] = mx;
1409  s->mv[0][0][1] = my;
1410  }
1411  } else {
1413  s->mv_type = MV_TYPE_8X8;
1414  for (i = 0; i < 4; i++) {
1415  mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
1416  mx = ff_h263_decode_motion(s, pred_x, s->f_code);
1417  if (mx >= 0xffff)
1418  return -1;
1419 
1420  my = ff_h263_decode_motion(s, pred_y, s->f_code);
1421  if (my >= 0xffff)
1422  return -1;
1423  s->mv[0][i][0] = mx;
1424  s->mv[0][i][1] = my;
1425  mot_val[0] = mx;
1426  mot_val[1] = my;
1427  }
1428  }
1429  } else if (s->pict_type == AV_PICTURE_TYPE_B) {
1430  int modb1; // first bit of modb
1431  int modb2; // second bit of modb
1432  int mb_type;
1433 
1434  s->mb_intra = 0; // B-frames never contain intra blocks
1435  s->mcsel = 0; // ... true gmc blocks
1436 
1437  if (s->mb_x == 0) {
1438  for (i = 0; i < 2; i++) {
1439  s->last_mv[i][0][0] =
1440  s->last_mv[i][0][1] =
1441  s->last_mv[i][1][0] =
1442  s->last_mv[i][1][1] = 0;
1443  }
1444 
1446  }
1447 
1448  /* if we skipped it in the future P Frame than skip it now too */
1449  s->mb_skipped = s->next_picture.mbskip_table[s->mb_y * s->mb_stride + s->mb_x]; // Note, skiptab=0 if last was GMC
1450 
1451  if (s->mb_skipped) {
1452  /* skip mb */
1453  for (i = 0; i < 6; i++)
1454  s->block_last_index[i] = -1;
1455 
1456  s->mv_dir = MV_DIR_FORWARD;
1457  s->mv_type = MV_TYPE_16X16;
1458  s->mv[0][0][0] =
1459  s->mv[0][0][1] =
1460  s->mv[1][0][0] =
1461  s->mv[1][0][1] = 0;
1463  MB_TYPE_16x16 |
1464  MB_TYPE_L0;
1465  goto end;
1466  }
1467 
1468  modb1 = get_bits1(&s->gb);
1469  if (modb1) {
1470  // like MB_TYPE_B_DIRECT but no vectors coded
1472  cbp = 0;
1473  } else {
1474  modb2 = get_bits1(&s->gb);
1475  mb_type = get_vlc2(&s->gb, mb_type_b_vlc.table, MB_TYPE_B_VLC_BITS, 1);
1476  if (mb_type < 0) {
1477  av_log(s->avctx, AV_LOG_ERROR, "illegal MB_type\n");
1478  return -1;
1479  }
1480  mb_type = mb_type_b_map[mb_type];
1481  if (modb2) {
1482  cbp = 0;
1483  } else {
1484  s->dsp.clear_blocks(s->block[0]);
1485  cbp = get_bits(&s->gb, 6);
1486  }
1487 
1488  if ((!IS_DIRECT(mb_type)) && cbp) {
1489  if (get_bits1(&s->gb))
1490  ff_set_qscale(s, s->qscale + get_bits1(&s->gb) * 4 - 2);
1491  }
1492 
1493  if (!s->progressive_sequence) {
1494  if (cbp)
1495  s->interlaced_dct = get_bits1(&s->gb);
1496 
1497  if (!IS_DIRECT(mb_type) && get_bits1(&s->gb)) {
1498  mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
1499  mb_type &= ~MB_TYPE_16x16;
1500 
1501  if (USES_LIST(mb_type, 0)) {
1502  s->field_select[0][0] = get_bits1(&s->gb);
1503  s->field_select[0][1] = get_bits1(&s->gb);
1504  }
1505  if (USES_LIST(mb_type, 1)) {
1506  s->field_select[1][0] = get_bits1(&s->gb);
1507  s->field_select[1][1] = get_bits1(&s->gb);
1508  }
1509  }
1510  }
1511 
1512  s->mv_dir = 0;
1513  if ((mb_type & (MB_TYPE_DIRECT2 | MB_TYPE_INTERLACED)) == 0) {
1514  s->mv_type = MV_TYPE_16X16;
1515 
1516  if (USES_LIST(mb_type, 0)) {
1517  s->mv_dir = MV_DIR_FORWARD;
1518 
1519  mx = ff_h263_decode_motion(s, s->last_mv[0][0][0], s->f_code);
1520  my = ff_h263_decode_motion(s, s->last_mv[0][0][1], s->f_code);
1521  s->last_mv[0][1][0] =
1522  s->last_mv[0][0][0] =
1523  s->mv[0][0][0] = mx;
1524  s->last_mv[0][1][1] =
1525  s->last_mv[0][0][1] =
1526  s->mv[0][0][1] = my;
1527  }
1528 
1529  if (USES_LIST(mb_type, 1)) {
1530  s->mv_dir |= MV_DIR_BACKWARD;
1531 
1532  mx = ff_h263_decode_motion(s, s->last_mv[1][0][0], s->b_code);
1533  my = ff_h263_decode_motion(s, s->last_mv[1][0][1], s->b_code);
1534  s->last_mv[1][1][0] =
1535  s->last_mv[1][0][0] =
1536  s->mv[1][0][0] = mx;
1537  s->last_mv[1][1][1] =
1538  s->last_mv[1][0][1] =
1539  s->mv[1][0][1] = my;
1540  }
1541  } else if (!IS_DIRECT(mb_type)) {
1542  s->mv_type = MV_TYPE_FIELD;
1543 
1544  if (USES_LIST(mb_type, 0)) {
1545  s->mv_dir = MV_DIR_FORWARD;
1546 
1547  for (i = 0; i < 2; i++) {
1548  mx = ff_h263_decode_motion(s, s->last_mv[0][i][0], s->f_code);
1549  my = ff_h263_decode_motion(s, s->last_mv[0][i][1] / 2, s->f_code);
1550  s->last_mv[0][i][0] =
1551  s->mv[0][i][0] = mx;
1552  s->last_mv[0][i][1] = (s->mv[0][i][1] = my) * 2;
1553  }
1554  }
1555 
1556  if (USES_LIST(mb_type, 1)) {
1557  s->mv_dir |= MV_DIR_BACKWARD;
1558 
1559  for (i = 0; i < 2; i++) {
1560  mx = ff_h263_decode_motion(s, s->last_mv[1][i][0], s->b_code);
1561  my = ff_h263_decode_motion(s, s->last_mv[1][i][1] / 2, s->b_code);
1562  s->last_mv[1][i][0] =
1563  s->mv[1][i][0] = mx;
1564  s->last_mv[1][i][1] = (s->mv[1][i][1] = my) * 2;
1565  }
1566  }
1567  }
1568  }
1569 
1570  if (IS_DIRECT(mb_type)) {
1571  if (IS_SKIP(mb_type)) {
1572  mx =
1573  my = 0;
1574  } else {
1575  mx = ff_h263_decode_motion(s, 0, 1);
1576  my = ff_h263_decode_motion(s, 0, 1);
1577  }
1578 
1580  mb_type |= ff_mpeg4_set_direct_mv(s, mx, my);
1581  }
1582  s->current_picture.mb_type[xy] = mb_type;
1583  } else { /* I-Frame */
1584  do {
1586  if (cbpc < 0) {
1588  "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
1589  return -1;
1590  }
1591  } while (cbpc == 8);
1592 
1593  dquant = cbpc & 4;
1594  s->mb_intra = 1;
1595 
1596 intra:
1597  s->ac_pred = get_bits1(&s->gb);
1598  if (s->ac_pred)
1600  else
1602 
1603  cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
1604  if (cbpy < 0) {
1606  "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
1607  return -1;
1608  }
1609  cbp = (cbpc & 3) | (cbpy << 2);
1610 
1611  ctx->use_intra_dc_vlc = s->qscale < ctx->intra_dc_threshold;
1612 
1613  if (dquant)
1614  ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
1615 
1616  if (!s->progressive_sequence)
1617  s->interlaced_dct = get_bits1(&s->gb);
1618 
1619  s->dsp.clear_blocks(s->block[0]);
1620  /* decode each block */
1621  for (i = 0; i < 6; i++) {
1622  if (mpeg4_decode_block(ctx, block[i], i, cbp & 32, 1, 0) < 0)
1623  return -1;
1624  cbp += cbp;
1625  }
1626  goto end;
1627  }
1628 
1629  /* decode each block */
1630  for (i = 0; i < 6; i++) {
1631  if (mpeg4_decode_block(ctx, block[i], i, cbp & 32, 0, 0) < 0)
1632  return -1;
1633  cbp += cbp;
1634  }
1635 
1636 end:
1637  /* per-MB end of slice check */
1638  if (s->codec_id == AV_CODEC_ID_MPEG4) {
1639  int next = mpeg4_is_resync(ctx);
1640  if (next) {
1641  if (s->mb_x + s->mb_y*s->mb_width + 1 > next && (s->avctx->err_recognition & AV_EF_AGGRESSIVE)) {
1642  return -1;
1643  } else if (s->mb_x + s->mb_y*s->mb_width + 1 >= next)
1644  return SLICE_END;
1645 
1646  if (s->pict_type == AV_PICTURE_TYPE_B) {
1647  const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
1649  (s->mb_x + delta >= s->mb_width)
1650  ? FFMIN(s->mb_y + 1, s->mb_height - 1)
1651  : s->mb_y, 0);
1652  if (s->next_picture.mbskip_table[xy + delta])
1653  return SLICE_OK;
1654  }
1655 
1656  return SLICE_END;
1657  }
1658  }
1659 
1660  return SLICE_OK;
1661 }
1662 
1664 {
1665  int hours, minutes, seconds;
1666 
1667  if (!show_bits(gb, 23)) {
1668  av_log(s->avctx, AV_LOG_WARNING, "GOP header invalid\n");
1669  return -1;
1670  }
1671 
1672  hours = get_bits(gb, 5);
1673  minutes = get_bits(gb, 6);
1674  skip_bits1(gb);
1675  seconds = get_bits(gb, 6);
1676 
1677  s->time_base = seconds + 60*(minutes + 60*hours);
1678 
1679  skip_bits1(gb);
1680  skip_bits1(gb);
1681 
1682  return 0;
1683 }
1684 
1686 {
1687 
1688  s->avctx->profile = get_bits(gb, 4);
1689  s->avctx->level = get_bits(gb, 4);
1690 
1691  // for Simple profile, level 0
1692  if (s->avctx->profile == 0 && s->avctx->level == 8) {
1693  s->avctx->level = 0;
1694  }
1695 
1696  return 0;
1697 }
1698 
1700 {
1701  MpegEncContext *s = &ctx->m;
1702  int width, height, vo_ver_id;
1703 
1704  /* vol header */
1705  skip_bits(gb, 1); /* random access */
1706  s->vo_type = get_bits(gb, 8);
1707  if (get_bits1(gb) != 0) { /* is_ol_id */
1708  vo_ver_id = get_bits(gb, 4); /* vo_ver_id */
1709  skip_bits(gb, 3); /* vo_priority */
1710  } else {
1711  vo_ver_id = 1;
1712  }
1713  s->aspect_ratio_info = get_bits(gb, 4);
1715  s->avctx->sample_aspect_ratio.num = get_bits(gb, 8); // par_width
1716  s->avctx->sample_aspect_ratio.den = get_bits(gb, 8); // par_height
1717  } else {
1719  }
1720 
1721  if ((s->vol_control_parameters = get_bits1(gb))) { /* vol control parameter */
1722  int chroma_format = get_bits(gb, 2);
1723  if (chroma_format != CHROMA_420)
1724  av_log(s->avctx, AV_LOG_ERROR, "illegal chroma format\n");
1725 
1726  s->low_delay = get_bits1(gb);
1727  if (get_bits1(gb)) { /* vbv parameters */
1728  get_bits(gb, 15); /* first_half_bitrate */
1729  skip_bits1(gb); /* marker */
1730  get_bits(gb, 15); /* latter_half_bitrate */
1731  skip_bits1(gb); /* marker */
1732  get_bits(gb, 15); /* first_half_vbv_buffer_size */
1733  skip_bits1(gb); /* marker */
1734  get_bits(gb, 3); /* latter_half_vbv_buffer_size */
1735  get_bits(gb, 11); /* first_half_vbv_occupancy */
1736  skip_bits1(gb); /* marker */
1737  get_bits(gb, 15); /* latter_half_vbv_occupancy */
1738  skip_bits1(gb); /* marker */
1739  }
1740  } else {
1741  /* is setting low delay flag only once the smartest thing to do?
1742  * low delay detection won't be overriden. */
1743  if (s->picture_number == 0)
1744  s->low_delay = 0;
1745  }
1746 
1747  ctx->shape = get_bits(gb, 2); /* vol shape */
1748  if (ctx->shape != RECT_SHAPE)
1749  av_log(s->avctx, AV_LOG_ERROR, "only rectangular vol supported\n");
1750  if (ctx->shape == GRAY_SHAPE && vo_ver_id != 1) {
1751  av_log(s->avctx, AV_LOG_ERROR, "Gray shape not supported\n");
1752  skip_bits(gb, 4); /* video_object_layer_shape_extension */
1753  }
1754 
1755  check_marker(gb, "before time_increment_resolution");
1756 
1757  s->avctx->time_base.den = get_bits(gb, 16);
1758  if (!s->avctx->time_base.den) {
1759  av_log(s->avctx, AV_LOG_ERROR, "time_base.den==0\n");
1760  s->avctx->time_base.num = 0;
1761  return -1;
1762  }
1763 
1764  ctx->time_increment_bits = av_log2(s->avctx->time_base.den - 1) + 1;
1765  if (ctx->time_increment_bits < 1)
1766  ctx->time_increment_bits = 1;
1767 
1768  check_marker(gb, "before fixed_vop_rate");
1769 
1770  if (get_bits1(gb) != 0) /* fixed_vop_rate */
1772  else
1773  s->avctx->time_base.num = 1;
1774 
1775  ctx->t_frame = 0;
1776 
1777  if (ctx->shape != BIN_ONLY_SHAPE) {
1778  if (ctx->shape == RECT_SHAPE) {
1779  check_marker(gb, "before width");
1780  width = get_bits(gb, 13);
1781  check_marker(gb, "before height");
1782  height = get_bits(gb, 13);
1783  check_marker(gb, "after height");
1784  if (width && height && /* they should be non zero but who knows */
1785  !(s->width && s->codec_tag == AV_RL32("MP4S"))) {
1786  if (s->width && s->height &&
1787  (s->width != width || s->height != height))
1788  s->context_reinit = 1;
1789  s->width = width;
1790  s->height = height;
1791  }
1792  }
1793 
1795  s->progressive_frame = get_bits1(gb) ^ 1;
1796  s->interlaced_dct = 0;
1797  if (!get_bits1(gb) && (s->avctx->debug & FF_DEBUG_PICT_INFO))
1798  av_log(s->avctx, AV_LOG_INFO, /* OBMC Disable */
1799  "MPEG4 OBMC not supported (very likely buggy encoder)\n");
1800  if (vo_ver_id == 1)
1801  ctx->vol_sprite_usage = get_bits1(gb); /* vol_sprite_usage */
1802  else
1803  ctx->vol_sprite_usage = get_bits(gb, 2); /* vol_sprite_usage */
1804 
1805  if (ctx->vol_sprite_usage == STATIC_SPRITE)
1806  av_log(s->avctx, AV_LOG_ERROR, "Static Sprites not supported\n");
1807  if (ctx->vol_sprite_usage == STATIC_SPRITE ||
1808  ctx->vol_sprite_usage == GMC_SPRITE) {
1809  if (ctx->vol_sprite_usage == STATIC_SPRITE) {
1810  skip_bits(gb, 13); // sprite_width
1811  skip_bits1(gb); /* marker */
1812  skip_bits(gb, 13); // sprite_height
1813  skip_bits1(gb); /* marker */
1814  skip_bits(gb, 13); // sprite_left
1815  skip_bits1(gb); /* marker */
1816  skip_bits(gb, 13); // sprite_top
1817  skip_bits1(gb); /* marker */
1818  }
1819  ctx->num_sprite_warping_points = get_bits(gb, 6);
1820  if (ctx->num_sprite_warping_points > 3) {
1822  "%d sprite_warping_points\n",
1824  ctx->num_sprite_warping_points = 0;
1825  return -1;
1826  }
1827  s->sprite_warping_accuracy = get_bits(gb, 2);
1829  if (ctx->vol_sprite_usage == STATIC_SPRITE)
1830  skip_bits1(gb); // low_latency_sprite
1831  }
1832  // FIXME sadct disable bit if verid!=1 && shape not rect
1833 
1834  if (get_bits1(gb) == 1) { /* not_8_bit */
1835  s->quant_precision = get_bits(gb, 4); /* quant_precision */
1836  if (get_bits(gb, 4) != 8) /* bits_per_pixel */
1837  av_log(s->avctx, AV_LOG_ERROR, "N-bit not supported\n");
1838  if (s->quant_precision != 5)
1840  "quant precision %d\n", s->quant_precision);
1841  if (s->quant_precision<3 || s->quant_precision>9) {
1842  s->quant_precision = 5;
1843  }
1844  } else {
1845  s->quant_precision = 5;
1846  }
1847 
1848  // FIXME a bunch of grayscale shape things
1849 
1850  if ((s->mpeg_quant = get_bits1(gb))) { /* vol_quant_type */
1851  int i, v;
1852 
1853  /* load default matrixes */
1854  for (i = 0; i < 64; i++) {
1855  int j = s->dsp.idct_permutation[i];
1857  s->intra_matrix[j] = v;
1858  s->chroma_intra_matrix[j] = v;
1859 
1861  s->inter_matrix[j] = v;
1862  s->chroma_inter_matrix[j] = v;
1863  }
1864 
1865  /* load custom intra matrix */
1866  if (get_bits1(gb)) {
1867  int last = 0;
1868  for (i = 0; i < 64; i++) {
1869  int j;
1870  v = get_bits(gb, 8);
1871  if (v == 0)
1872  break;
1873 
1874  last = v;
1876  s->intra_matrix[j] = last;
1877  s->chroma_intra_matrix[j] = last;
1878  }
1879 
1880  /* replicate last value */
1881  for (; i < 64; i++) {
1882  int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
1883  s->intra_matrix[j] = last;
1884  s->chroma_intra_matrix[j] = last;
1885  }
1886  }
1887 
1888  /* load custom non intra matrix */
1889  if (get_bits1(gb)) {
1890  int last = 0;
1891  for (i = 0; i < 64; i++) {
1892  int j;
1893  v = get_bits(gb, 8);
1894  if (v == 0)
1895  break;
1896 
1897  last = v;
1899  s->inter_matrix[j] = v;
1900  s->chroma_inter_matrix[j] = v;
1901  }
1902 
1903  /* replicate last value */
1904  for (; i < 64; i++) {
1905  int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
1906  s->inter_matrix[j] = last;
1907  s->chroma_inter_matrix[j] = last;
1908  }
1909  }
1910 
1911  // FIXME a bunch of grayscale shape things
1912  }
1913 
1914  if (vo_ver_id != 1)
1915  s->quarter_sample = get_bits1(gb);
1916  else
1917  s->quarter_sample = 0;
1918 
1919  if (get_bits_left(gb) < 4) {
1920  av_log(s->avctx, AV_LOG_ERROR, "VOL Header truncated\n");
1921  return AVERROR_INVALIDDATA;
1922  }
1923 
1924  if (!get_bits1(gb)) {
1925  int pos = get_bits_count(gb);
1926  int estimation_method = get_bits(gb, 2);
1927  if (estimation_method < 2) {
1928  if (!get_bits1(gb)) {
1929  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* opaque */
1930  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* transparent */
1931  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* intra_cae */
1932  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* inter_cae */
1933  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* no_update */
1934  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* upampling */
1935  }
1936  if (!get_bits1(gb)) {
1937  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* intra_blocks */
1938  ctx->cplx_estimation_trash_p += 8 * get_bits1(gb); /* inter_blocks */
1939  ctx->cplx_estimation_trash_p += 8 * get_bits1(gb); /* inter4v_blocks */
1940  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* not coded blocks */
1941  }
1942  if (!check_marker(gb, "in complexity estimation part 1")) {
1943  skip_bits_long(gb, pos - get_bits_count(gb));
1944  goto no_cplx_est;
1945  }
1946  if (!get_bits1(gb)) {
1947  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* dct_coeffs */
1948  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* dct_lines */
1949  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* vlc_syms */
1950  ctx->cplx_estimation_trash_i += 4 * get_bits1(gb); /* vlc_bits */
1951  }
1952  if (!get_bits1(gb)) {
1953  ctx->cplx_estimation_trash_p += 8 * get_bits1(gb); /* apm */
1954  ctx->cplx_estimation_trash_p += 8 * get_bits1(gb); /* npm */
1955  ctx->cplx_estimation_trash_b += 8 * get_bits1(gb); /* interpolate_mc_q */
1956  ctx->cplx_estimation_trash_p += 8 * get_bits1(gb); /* forwback_mc_q */
1957  ctx->cplx_estimation_trash_p += 8 * get_bits1(gb); /* halfpel2 */
1958  ctx->cplx_estimation_trash_p += 8 * get_bits1(gb); /* halfpel4 */
1959  }
1960  if (!check_marker(gb, "in complexity estimation part 2")) {
1961  skip_bits_long(gb, pos - get_bits_count(gb));
1962  goto no_cplx_est;
1963  }
1964  if (estimation_method == 1) {
1965  ctx->cplx_estimation_trash_i += 8 * get_bits1(gb); /* sadct */
1966  ctx->cplx_estimation_trash_p += 8 * get_bits1(gb); /* qpel */
1967  }
1968  } else
1970  "Invalid Complexity estimation method %d\n",
1971  estimation_method);
1972  } else {
1973 
1974 no_cplx_est:
1977  ctx->cplx_estimation_trash_b = 0;
1978  }
1979 
1980  ctx->resync_marker = !get_bits1(gb); /* resync_marker_disabled */
1981 
1982  s->data_partitioning = get_bits1(gb);
1983  if (s->data_partitioning)
1984  ctx->rvlc = get_bits1(gb);
1985 
1986  if (vo_ver_id != 1) {
1987  ctx->new_pred = get_bits1(gb);
1988  if (ctx->new_pred) {
1989  av_log(s->avctx, AV_LOG_ERROR, "new pred not supported\n");
1990  skip_bits(gb, 2); /* requested upstream message type */
1991  skip_bits1(gb); /* newpred segment type */
1992  }
1993  if (get_bits1(gb)) // reduced_res_vop
1995  "reduced resolution VOP not supported\n");
1996  } else {
1997  ctx->new_pred = 0;
1998  }
1999 
2000  ctx->scalability = get_bits1(gb);
2001 
2002  if (ctx->scalability) {
2003  GetBitContext bak = *gb;
2004  int h_sampling_factor_n;
2005  int h_sampling_factor_m;
2006  int v_sampling_factor_n;
2007  int v_sampling_factor_m;
2008 
2009  skip_bits1(gb); // hierarchy_type
2010  skip_bits(gb, 4); /* ref_layer_id */
2011  skip_bits1(gb); /* ref_layer_sampling_dir */
2012  h_sampling_factor_n = get_bits(gb, 5);
2013  h_sampling_factor_m = get_bits(gb, 5);
2014  v_sampling_factor_n = get_bits(gb, 5);
2015  v_sampling_factor_m = get_bits(gb, 5);
2016  ctx->enhancement_type = get_bits1(gb);
2017 
2018  if (h_sampling_factor_n == 0 || h_sampling_factor_m == 0 ||
2019  v_sampling_factor_n == 0 || v_sampling_factor_m == 0) {
2020  /* illegal scalability header (VERY broken encoder),
2021  * trying to workaround */
2022  ctx->scalability = 0;
2023  *gb = bak;
2024  } else
2025  av_log(s->avctx, AV_LOG_ERROR, "scalability not supported\n");
2026 
2027  // bin shape stuff FIXME
2028  }
2029  }
2030 
2031  if (s->avctx->debug&FF_DEBUG_PICT_INFO) {
2032  av_log(s->avctx, AV_LOG_DEBUG, "tb %d/%d, tincrbits:%d, qp_prec:%d, ps:%d, %s%s%s%s\n",
2033  s->avctx->time_base.num, s->avctx->time_base.den,
2034  ctx->time_increment_bits,
2035  s->quant_precision,
2037  ctx->scalability ? "scalability " :"" , s->quarter_sample ? "qpel " : "",
2038  s->data_partitioning ? "partition " : "", ctx->rvlc ? "rvlc " : ""
2039  );
2040  }
2041 
2042  return 0;
2043 }
2044 
2045 /**
2046  * Decode the user data stuff in the header.
2047  * Also initializes divx/xvid/lavc_version/build.
2048  */
2050 {
2051  MpegEncContext *s = &ctx->m;
2052  char buf[256];
2053  int i;
2054  int e;
2055  int ver = 0, build = 0, ver2 = 0, ver3 = 0;
2056  char last;
2057 
2058  for (i = 0; i < 255 && get_bits_count(gb) < gb->size_in_bits; i++) {
2059  if (show_bits(gb, 23) == 0)
2060  break;
2061  buf[i] = get_bits(gb, 8);
2062  }
2063  buf[i] = 0;
2064 
2065  /* divx detection */
2066  e = sscanf(buf, "DivX%dBuild%d%c", &ver, &build, &last);
2067  if (e < 2)
2068  e = sscanf(buf, "DivX%db%d%c", &ver, &build, &last);
2069  if (e >= 2) {
2070  ctx->divx_version = ver;
2071  ctx->divx_build = build;
2072  s->divx_packed = e == 3 && last == 'p';
2073  if (s->divx_packed && !ctx->showed_packed_warning) {
2074  av_log(s->avctx, AV_LOG_INFO, "Video uses a non-standard and "
2075  "wasteful way to store B-frames ('packed B-frames'). "
2076  "Consider using a tool like VirtualDub or avidemux to fix it.\n");
2077  ctx->showed_packed_warning = 1;
2078  }
2079  }
2080 
2081  /* libavcodec detection */
2082  e = sscanf(buf, "FFmpe%*[^b]b%d", &build) + 3;
2083  if (e != 4)
2084  e = sscanf(buf, "FFmpeg v%d.%d.%d / libavcodec build: %d", &ver, &ver2, &ver3, &build);
2085  if (e != 4) {
2086  e = sscanf(buf, "Lavc%d.%d.%d", &ver, &ver2, &ver3) + 1;
2087  if (e > 1)
2088  build = (ver << 16) + (ver2 << 8) + ver3;
2089  }
2090  if (e != 4) {
2091  if (strcmp(buf, "ffmpeg") == 0)
2092  ctx->lavc_build = 4600;
2093  }
2094  if (e == 4)
2095  ctx->lavc_build = build;
2096 
2097  /* Xvid detection */
2098  e = sscanf(buf, "XviD%d", &build);
2099  if (e == 1)
2100  ctx->xvid_build = build;
2101 
2102  return 0;
2103 }
2104 
2106 {
2107  Mpeg4DecContext *ctx = avctx->priv_data;
2108  MpegEncContext *s = &ctx->m;
2109 
2110  if (ctx->xvid_build == -1 && ctx->divx_version == -1 && ctx->lavc_build == -1) {
2111  if (s->stream_codec_tag == AV_RL32("XVID") ||
2112  s->codec_tag == AV_RL32("XVID") ||
2113  s->codec_tag == AV_RL32("XVIX") ||
2114  s->codec_tag == AV_RL32("RMP4") ||
2115  s->codec_tag == AV_RL32("ZMP4") ||
2116  s->codec_tag == AV_RL32("SIPP"))
2117  ctx->xvid_build = 0;
2118  }
2119 
2120  if (ctx->xvid_build == -1 && ctx->divx_version == -1 && ctx->lavc_build == -1)
2121  if (s->codec_tag == AV_RL32("DIVX") && s->vo_type == 0 &&
2122  s->vol_control_parameters == 0)
2123  ctx->divx_version = 400; // divx 4
2124 
2125  if (ctx->xvid_build >= 0 && ctx->divx_version >= 0) {
2126  ctx->divx_version =
2127  ctx->divx_build = -1;
2128  }
2129 
2131  if (s->codec_tag == AV_RL32("XVIX"))
2133 
2134  if (s->codec_tag == AV_RL32("UMP4"))
2136 
2137  if (ctx->divx_version >= 500 && ctx->divx_build < 1814)
2139 
2140  if (ctx->divx_version > 502 && ctx->divx_build < 1814)
2142 
2143  if (ctx->xvid_build <= 3U)
2144  s->padding_bug_score = 256 * 256 * 256 * 64;
2145 
2146  if (ctx->xvid_build <= 1U)
2148 
2149  if (ctx->xvid_build <= 12U)
2151 
2152  if (ctx->xvid_build <= 32U)
2154 
2155 #define SET_QPEL_FUNC(postfix1, postfix2) \
2156  s->dsp.put_ ## postfix1 = ff_put_ ## postfix2; \
2157  s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2; \
2158  s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
2159 
2160  if (ctx->lavc_build < 4653U)
2162 
2163  if (ctx->lavc_build < 4655U)
2165 
2166  if (ctx->lavc_build < 4670U)
2168 
2169  if (ctx->lavc_build <= 4712U)
2171 
2172  if (ctx->divx_version >= 0)
2174  if (ctx->divx_version == 501 && ctx->divx_build == 20020416)
2175  s->padding_bug_score = 256 * 256 * 256 * 64;
2176 
2177  if (ctx->divx_version < 500U)
2179 
2180  if (ctx->divx_version >= 0)
2182  }
2183 
2184  if (s->workaround_bugs & FF_BUG_STD_QPEL) {
2185  SET_QPEL_FUNC(qpel_pixels_tab[0][5], qpel16_mc11_old_c)
2186  SET_QPEL_FUNC(qpel_pixels_tab[0][7], qpel16_mc31_old_c)
2187  SET_QPEL_FUNC(qpel_pixels_tab[0][9], qpel16_mc12_old_c)
2188  SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
2189  SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
2190  SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
2191 
2192  SET_QPEL_FUNC(qpel_pixels_tab[1][5], qpel8_mc11_old_c)
2193  SET_QPEL_FUNC(qpel_pixels_tab[1][7], qpel8_mc31_old_c)
2194  SET_QPEL_FUNC(qpel_pixels_tab[1][9], qpel8_mc12_old_c)
2195  SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
2196  SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
2197  SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
2198  }
2199 
2200  if (avctx->debug & FF_DEBUG_BUGS)
2202  "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
2203  s->workaround_bugs, ctx->lavc_build, ctx->xvid_build,
2204  ctx->divx_version, ctx->divx_build, s->divx_packed ? "p" : "");
2205 
2206 #if HAVE_MMX
2207  if (s->codec_id == AV_CODEC_ID_MPEG4 && ctx->xvid_build >= 0 &&
2208  avctx->idct_algo == FF_IDCT_AUTO &&
2210  avctx->idct_algo = FF_IDCT_XVIDMMX;
2211  ff_dct_common_init(s);
2212  return 1;
2213  }
2214 #endif
2215  return 0;
2216 }
2217 
2219 {
2220  MpegEncContext *s = &ctx->m;
2221  int time_incr, time_increment;
2222  int64_t pts;
2223 
2224  s->pict_type = get_bits(gb, 2) + AV_PICTURE_TYPE_I; /* pict type: I = 0 , P = 1 */
2225  if (s->pict_type == AV_PICTURE_TYPE_B && s->low_delay &&
2226  s->vol_control_parameters == 0 && !(s->flags & CODEC_FLAG_LOW_DELAY)) {
2227  av_log(s->avctx, AV_LOG_ERROR, "low_delay flag incorrectly, clearing it\n");
2228  s->low_delay = 0;
2229  }
2230 
2232  if (s->partitioned_frame)
2234  else
2236 
2237  time_incr = 0;
2238  while (get_bits1(gb) != 0)
2239  time_incr++;
2240 
2241  check_marker(gb, "before time_increment");
2242 
2243  if (ctx->time_increment_bits == 0 ||
2244  !(show_bits(gb, ctx->time_increment_bits + 1) & 1)) {
2246  "hmm, seems the headers are not complete, trying to guess time_increment_bits\n");
2247 
2248  for (ctx->time_increment_bits = 1;
2249  ctx->time_increment_bits < 16;
2250  ctx->time_increment_bits++) {
2251  if (s->pict_type == AV_PICTURE_TYPE_P ||
2252  (s->pict_type == AV_PICTURE_TYPE_S &&
2253  ctx->vol_sprite_usage == GMC_SPRITE)) {
2254  if ((show_bits(gb, ctx->time_increment_bits + 6) & 0x37) == 0x30)
2255  break;
2256  } else if ((show_bits(gb, ctx->time_increment_bits + 5) & 0x1F) == 0x18)
2257  break;
2258  }
2259 
2261  "my guess is %d bits ;)\n", ctx->time_increment_bits);
2262  if (s->avctx->time_base.den && 4*s->avctx->time_base.den < 1<<ctx->time_increment_bits) {
2263  s->avctx->time_base.den = 1<<ctx->time_increment_bits;
2264  }
2265  }
2266 
2267  if (IS_3IV1)
2268  time_increment = get_bits1(gb); // FIXME investigate further
2269  else
2270  time_increment = get_bits(gb, ctx->time_increment_bits);
2271 
2272  if (s->pict_type != AV_PICTURE_TYPE_B) {
2273  s->last_time_base = s->time_base;
2274  s->time_base += time_incr;
2275  s->time = s->time_base * s->avctx->time_base.den + time_increment;
2276  if (s->workaround_bugs & FF_BUG_UMP4) {
2277  if (s->time < s->last_non_b_time) {
2278  /* header is not mpeg-4-compatible, broken encoder,
2279  * trying to workaround */
2280  s->time_base++;
2281  s->time += s->avctx->time_base.den;
2282  }
2283  }
2284  s->pp_time = s->time - s->last_non_b_time;
2285  s->last_non_b_time = s->time;
2286  } else {
2287  s->time = (s->last_time_base + time_incr) * s->avctx->time_base.den + time_increment;
2288  s->pb_time = s->pp_time - (s->last_non_b_time - s->time);
2289  if (s->pp_time <= s->pb_time ||
2290  s->pp_time <= s->pp_time - s->pb_time ||
2291  s->pp_time <= 0) {
2292  /* messed up order, maybe after seeking? skipping current b-frame */
2293  return FRAME_SKIPPED;
2294  }
2296 
2297  if (ctx->t_frame == 0)
2298  ctx->t_frame = s->pb_time;
2299  if (ctx->t_frame == 0)
2300  ctx->t_frame = 1; // 1/0 protection
2302  ROUNDED_DIV(s->last_non_b_time - s->pp_time, ctx->t_frame)) * 2;
2303  s->pb_field_time = (ROUNDED_DIV(s->time, ctx->t_frame) -
2304  ROUNDED_DIV(s->last_non_b_time - s->pp_time, ctx->t_frame)) * 2;
2305  if (s->pp_field_time <= s->pb_field_time || s->pb_field_time <= 1) {
2306  s->pb_field_time = 2;
2307  s->pp_field_time = 4;
2308  if (!s->progressive_sequence)
2309  return FRAME_SKIPPED;
2310  }
2311  }
2312 
2313  if (s->avctx->time_base.num)
2314  pts = ROUNDED_DIV(s->time, s->avctx->time_base.num);
2315  else
2316  pts = AV_NOPTS_VALUE;
2317  if (s->avctx->debug&FF_DEBUG_PTS)
2318  av_log(s->avctx, AV_LOG_DEBUG, "MPEG4 PTS: %"PRId64"\n",
2319  pts);
2320 
2321  check_marker(gb, "before vop_coded");
2322 
2323  /* vop coded */
2324  if (get_bits1(gb) != 1) {
2325  if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2326  av_log(s->avctx, AV_LOG_ERROR, "vop not coded\n");
2327  return FRAME_SKIPPED;
2328  }
2329  if (ctx->new_pred)
2330  decode_new_pred(ctx, gb);
2331 
2332  if (ctx->shape != BIN_ONLY_SHAPE &&
2333  (s->pict_type == AV_PICTURE_TYPE_P ||
2334  (s->pict_type == AV_PICTURE_TYPE_S &&
2335  ctx->vol_sprite_usage == GMC_SPRITE))) {
2336  /* rounding type for motion estimation */
2337  s->no_rounding = get_bits1(gb);
2338  } else {
2339  s->no_rounding = 0;
2340  }
2341  // FIXME reduced res stuff
2342 
2343  if (ctx->shape != RECT_SHAPE) {
2344  if (ctx->vol_sprite_usage != 1 || s->pict_type != AV_PICTURE_TYPE_I) {
2345  skip_bits(gb, 13); /* width */
2346  skip_bits1(gb); /* marker */
2347  skip_bits(gb, 13); /* height */
2348  skip_bits1(gb); /* marker */
2349  skip_bits(gb, 13); /* hor_spat_ref */
2350  skip_bits1(gb); /* marker */
2351  skip_bits(gb, 13); /* ver_spat_ref */
2352  }
2353  skip_bits1(gb); /* change_CR_disable */
2354 
2355  if (get_bits1(gb) != 0)
2356  skip_bits(gb, 8); /* constant_alpha_value */
2357  }
2358 
2359  // FIXME complexity estimation stuff
2360 
2361  if (ctx->shape != BIN_ONLY_SHAPE) {
2363  if (s->pict_type != AV_PICTURE_TYPE_I)
2365  if (s->pict_type == AV_PICTURE_TYPE_B)
2367 
2368  if (get_bits_left(gb) < 3) {
2369  av_log(s->avctx, AV_LOG_ERROR, "Header truncated\n");
2370  return -1;
2371  }
2373  if (!s->progressive_sequence) {
2374  s->top_field_first = get_bits1(gb);
2375  s->alternate_scan = get_bits1(gb);
2376  } else
2377  s->alternate_scan = 0;
2378  }
2379 
2380  if (s->alternate_scan) {
2385  } else {
2390  }
2391 
2392  if (s->pict_type == AV_PICTURE_TYPE_S &&
2393  (ctx->vol_sprite_usage == STATIC_SPRITE ||
2394  ctx->vol_sprite_usage == GMC_SPRITE)) {
2395  if (mpeg4_decode_sprite_trajectory(ctx, gb) < 0)
2396  return AVERROR_INVALIDDATA;
2397  if (ctx->sprite_brightness_change)
2399  "sprite_brightness_change not supported\n");
2400  if (ctx->vol_sprite_usage == STATIC_SPRITE)
2401  av_log(s->avctx, AV_LOG_ERROR, "static sprite not supported\n");
2402  }
2403 
2404  if (ctx->shape != BIN_ONLY_SHAPE) {
2405  s->chroma_qscale = s->qscale = get_bits(gb, s->quant_precision);
2406  if (s->qscale == 0) {
2408  "Error, header damaged or not MPEG4 header (qscale=0)\n");
2409  return -1; // makes no sense to continue, as there is nothing left from the image then
2410  }
2411 
2412  if (s->pict_type != AV_PICTURE_TYPE_I) {
2413  s->f_code = get_bits(gb, 3); /* fcode_for */
2414  if (s->f_code == 0) {
2416  "Error, header damaged or not MPEG4 header (f_code=0)\n");
2417  s->f_code = 1;
2418  return -1; // makes no sense to continue, as there is nothing left from the image then
2419  }
2420  } else
2421  s->f_code = 1;
2422 
2423  if (s->pict_type == AV_PICTURE_TYPE_B) {
2424  s->b_code = get_bits(gb, 3);
2425  if (s->b_code == 0) {
2427  "Error, header damaged or not MPEG4 header (b_code=0)\n");
2428  s->b_code=1;
2429  return -1; // makes no sense to continue, as the MV decoding will break very quickly
2430  }
2431  } else
2432  s->b_code = 1;
2433 
2434  if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
2436  "qp:%d fc:%d,%d %s size:%d pro:%d alt:%d top:%d %spel part:%d resync:%d w:%d a:%d rnd:%d vot:%d%s dc:%d ce:%d/%d/%d time:%"PRId64" tincr:%d\n",
2437  s->qscale, s->f_code, s->b_code,
2438  s->pict_type == AV_PICTURE_TYPE_I ? "I" : (s->pict_type == AV_PICTURE_TYPE_P ? "P" : (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
2440  s->top_field_first, s->quarter_sample ? "q" : "h",
2443  1 - s->no_rounding, s->vo_type,
2444  s->vol_control_parameters ? " VOLC" : " ", ctx->intra_dc_threshold,
2447  s->time,
2448  time_increment
2449  );
2450  }
2451 
2452  if (!ctx->scalability) {
2453  if (ctx->shape != RECT_SHAPE && s->pict_type != AV_PICTURE_TYPE_I)
2454  skip_bits1(gb); // vop shape coding type
2455  } else {
2456  if (ctx->enhancement_type) {
2457  int load_backward_shape = get_bits1(gb);
2458  if (load_backward_shape)
2460  "load backward shape isn't supported\n");
2461  }
2462  skip_bits(gb, 2); // ref_select_code
2463  }
2464  }
2465  /* detect buggy encoders which don't set the low_delay flag
2466  * (divx4/xvid/opendivx). Note we cannot detect divx5 without b-frames
2467  * easily (although it's buggy too) */
2468  if (s->vo_type == 0 && s->vol_control_parameters == 0 &&
2469  ctx->divx_version == -1 && s->picture_number == 0) {
2471  "looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");
2472  s->low_delay = 1;
2473  }
2474 
2475  s->picture_number++; // better than pic number==0 always ;)
2476 
2477  // FIXME add short header support
2480 
2481  if (s->workaround_bugs & FF_BUG_EDGE) {
2482  s->h_edge_pos = s->width;
2483  s->v_edge_pos = s->height;
2484  }
2485  return 0;
2486 }
2487 
2488 /**
2489  * Decode mpeg4 headers.
2490  * @return <0 if no VOP found (or a damaged one)
2491  * FRAME_SKIPPED if a not coded VOP is found
2492  * 0 if a VOP is found
2493  */
2495 {
2496  MpegEncContext *s = &ctx->m;
2497  unsigned startcode, v;
2498 
2499  /* search next start code */
2500  align_get_bits(gb);
2501 
2502  if (s->codec_tag == AV_RL32("WV1F") && show_bits(gb, 24) == 0x575630) {
2503  skip_bits(gb, 24);
2504  if (get_bits(gb, 8) == 0xF0)
2505  goto end;
2506  }
2507 
2508  startcode = 0xff;
2509  for (;;) {
2510  if (get_bits_count(gb) >= gb->size_in_bits) {
2511  if (gb->size_in_bits == 8 &&
2512  (ctx->divx_version >= 0 || ctx->xvid_build >= 0) || s->codec_tag == AV_RL32("QMP4")) {
2513  av_log(s->avctx, AV_LOG_VERBOSE, "frame skip %d\n", gb->size_in_bits);
2514  return FRAME_SKIPPED; // divx bug
2515  } else
2516  return -1; // end of stream
2517  }
2518 
2519  /* use the bits after the test */
2520  v = get_bits(gb, 8);
2521  startcode = ((startcode << 8) | v) & 0xffffffff;
2522 
2523  if ((startcode & 0xFFFFFF00) != 0x100)
2524  continue; // no startcode
2525 
2526  if (s->avctx->debug & FF_DEBUG_STARTCODE) {
2527  av_log(s->avctx, AV_LOG_DEBUG, "startcode: %3X ", startcode);
2528  if (startcode <= 0x11F)
2529  av_log(s->avctx, AV_LOG_DEBUG, "Video Object Start");
2530  else if (startcode <= 0x12F)
2531  av_log(s->avctx, AV_LOG_DEBUG, "Video Object Layer Start");
2532  else if (startcode <= 0x13F)
2533  av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
2534  else if (startcode <= 0x15F)
2535  av_log(s->avctx, AV_LOG_DEBUG, "FGS bp start");
2536  else if (startcode <= 0x1AF)
2537  av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
2538  else if (startcode == 0x1B0)
2539  av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq Start");
2540  else if (startcode == 0x1B1)
2541  av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq End");
2542  else if (startcode == 0x1B2)
2543  av_log(s->avctx, AV_LOG_DEBUG, "User Data");
2544  else if (startcode == 0x1B3)
2545  av_log(s->avctx, AV_LOG_DEBUG, "Group of VOP start");
2546  else if (startcode == 0x1B4)
2547  av_log(s->avctx, AV_LOG_DEBUG, "Video Session Error");
2548  else if (startcode == 0x1B5)
2549  av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Start");
2550  else if (startcode == 0x1B6)
2551  av_log(s->avctx, AV_LOG_DEBUG, "Video Object Plane start");
2552  else if (startcode == 0x1B7)
2553  av_log(s->avctx, AV_LOG_DEBUG, "slice start");
2554  else if (startcode == 0x1B8)
2555  av_log(s->avctx, AV_LOG_DEBUG, "extension start");
2556  else if (startcode == 0x1B9)
2557  av_log(s->avctx, AV_LOG_DEBUG, "fgs start");
2558  else if (startcode == 0x1BA)
2559  av_log(s->avctx, AV_LOG_DEBUG, "FBA Object start");
2560  else if (startcode == 0x1BB)
2561  av_log(s->avctx, AV_LOG_DEBUG, "FBA Object Plane start");
2562  else if (startcode == 0x1BC)
2563  av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object start");
2564  else if (startcode == 0x1BD)
2565  av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object Plane start");
2566  else if (startcode == 0x1BE)
2567  av_log(s->avctx, AV_LOG_DEBUG, "Still Texture Object start");
2568  else if (startcode == 0x1BF)
2569  av_log(s->avctx, AV_LOG_DEBUG, "Texture Spatial Layer start");
2570  else if (startcode == 0x1C0)
2571  av_log(s->avctx, AV_LOG_DEBUG, "Texture SNR Layer start");
2572  else if (startcode == 0x1C1)
2573  av_log(s->avctx, AV_LOG_DEBUG, "Texture Tile start");
2574  else if (startcode == 0x1C2)
2575  av_log(s->avctx, AV_LOG_DEBUG, "Texture Shape Layer start");
2576  else if (startcode == 0x1C3)
2577  av_log(s->avctx, AV_LOG_DEBUG, "stuffing start");
2578  else if (startcode <= 0x1C5)
2579  av_log(s->avctx, AV_LOG_DEBUG, "reserved");
2580  else if (startcode <= 0x1FF)
2581  av_log(s->avctx, AV_LOG_DEBUG, "System start");
2582  av_log(s->avctx, AV_LOG_DEBUG, " at %d\n", get_bits_count(gb));
2583  }
2584 
2585  if (startcode >= 0x120 && startcode <= 0x12F) {
2586  if (decode_vol_header(ctx, gb) < 0)
2587  return -1;
2588  } else if (startcode == USER_DATA_STARTCODE) {
2589  decode_user_data(ctx, gb);
2590  } else if (startcode == GOP_STARTCODE) {
2591  mpeg4_decode_gop_header(s, gb);
2592  } else if (startcode == VOS_STARTCODE) {
2594  } else if (startcode == VOP_STARTCODE) {
2595  break;
2596  }
2597 
2598  align_get_bits(gb);
2599  startcode = 0xff;
2600  }
2601 
2602 end:
2603  if (s->flags & CODEC_FLAG_LOW_DELAY)
2604  s->low_delay = 1;
2605  s->avctx->has_b_frames = !s->low_delay;
2606 
2607  return decode_vop_header(ctx, gb);
2608 }
2609 
2611  static int done = 0;
2612 
2613  if (!done) {
2620  INIT_VLC_STATIC(&dc_lum, DC_VLC_BITS, 10 /* 13 */,
2621  &ff_mpeg4_DCtab_lum[0][1], 2, 1,
2622  &ff_mpeg4_DCtab_lum[0][0], 2, 1, 512);
2623  INIT_VLC_STATIC(&dc_chrom, DC_VLC_BITS, 10 /* 13 */,
2624  &ff_mpeg4_DCtab_chrom[0][1], 2, 1,
2625  &ff_mpeg4_DCtab_chrom[0][0], 2, 1, 512);
2626  INIT_VLC_STATIC(&sprite_trajectory, SPRITE_TRAJ_VLC_BITS, 15,
2627  &ff_sprite_trajectory_tab[0][1], 4, 2,
2628  &ff_sprite_trajectory_tab[0][0], 4, 2, 128);
2629  INIT_VLC_STATIC(&mb_type_b_vlc, MB_TYPE_B_VLC_BITS, 4,
2630  &ff_mb_type_b_tab[0][1], 2, 1,
2631  &ff_mb_type_b_tab[0][0], 2, 1, 16);
2632  done = 1;
2633  }
2634 }
2635 
2636 int ff_mpeg4_frame_end(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
2637 {
2638  Mpeg4DecContext *ctx = avctx->priv_data;
2639  MpegEncContext *s = &ctx->m;
2640 
2641  /* divx 5.01+ bitstream reorder stuff */
2642  /* Since this clobbers the input buffer and hwaccel codecs still need the
2643  * data during hwaccel->end_frame we should not do this any earlier */
2644  if (s->divx_packed) {
2645  int current_pos = s->gb.buffer == s->bitstream_buffer ? 0 : (get_bits_count(&s->gb) >> 3);
2646  int startcode_found = 0;
2647 
2648  if (buf_size - current_pos > 7) {
2649 
2650  int i;
2651  for (i = current_pos; i < buf_size - 4; i++)
2652 
2653  if (buf[i] == 0 &&
2654  buf[i + 1] == 0 &&
2655  buf[i + 2] == 1 &&
2656  buf[i + 3] == 0xB6) {
2657  startcode_found = !(buf[i + 4] & 0x40);
2658  break;
2659  }
2660  }
2661 
2662  if (startcode_found) {
2665  buf_size - current_pos);
2666  if (!s->bitstream_buffer)
2667  return AVERROR(ENOMEM);
2668  memcpy(s->bitstream_buffer, buf + current_pos,
2669  buf_size - current_pos);
2670  s->bitstream_buffer_size = buf_size - current_pos;
2671  }
2672  }
2673 
2674  return 0;
2675 }
2676 
2678  const AVCodecContext *src)
2679 {
2680  Mpeg4DecContext *s = dst->priv_data;
2681  const Mpeg4DecContext *s1 = src->priv_data;
2682 
2683  int ret = ff_mpeg_update_thread_context(dst, src);
2684 
2685  if (ret < 0)
2686  return ret;
2687 
2688  memcpy(((uint8_t*)s) + sizeof(MpegEncContext), ((uint8_t*)s1) + sizeof(MpegEncContext), sizeof(Mpeg4DecContext) - sizeof(MpegEncContext));
2689 
2690  return 0;
2691 }
2692 
2694 {
2695  Mpeg4DecContext *ctx = avctx->priv_data;
2696  MpegEncContext *s = &ctx->m;
2697  int ret;
2698 
2699  ctx->divx_version =
2700  ctx->divx_build =
2701  ctx->xvid_build =
2702  ctx->lavc_build = -1;
2703 
2704  if ((ret = ff_h263_decode_init(avctx)) < 0)
2705  return ret;
2706 
2708 
2709  s->h263_pred = 1;
2710  s->low_delay = 0; /* default, might be overridden in the vol header during header parsing */
2712  ctx->time_increment_bits = 4; /* default value for broken headers */
2713 
2715  avctx->internal->allocate_progress = 1;
2716 
2717  return 0;
2718 }
2719 
2721  { FF_PROFILE_MPEG4_SIMPLE, "Simple Profile" },
2722  { FF_PROFILE_MPEG4_SIMPLE_SCALABLE, "Simple Scalable Profile" },
2723  { FF_PROFILE_MPEG4_CORE, "Core Profile" },
2724  { FF_PROFILE_MPEG4_MAIN, "Main Profile" },
2725  { FF_PROFILE_MPEG4_N_BIT, "N-bit Profile" },
2726  { FF_PROFILE_MPEG4_SCALABLE_TEXTURE, "Scalable Texture Profile" },
2727  { FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION, "Simple Face Animation Profile" },
2728  { FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE, "Basic Animated Texture Profile" },
2729  { FF_PROFILE_MPEG4_HYBRID, "Hybrid Profile" },
2730  { FF_PROFILE_MPEG4_ADVANCED_REAL_TIME, "Advanced Real Time Simple Profile" },
2731  { FF_PROFILE_MPEG4_CORE_SCALABLE, "Code Scalable Profile" },
2732  { FF_PROFILE_MPEG4_ADVANCED_CODING, "Advanced Coding Profile" },
2733  { FF_PROFILE_MPEG4_ADVANCED_CORE, "Advanced Core Profile" },
2734  { FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE, "Advanced Scalable Texture Profile" },
2735  { FF_PROFILE_MPEG4_SIMPLE_STUDIO, "Simple Studio Profile" },
2736  { FF_PROFILE_MPEG4_ADVANCED_SIMPLE, "Advanced Simple Profile" },
2737  { FF_PROFILE_UNKNOWN },
2738 };
2739 
2740 static const AVOption mpeg4_options[] = {
2741  {"quarter_sample", "1/4 subpel MC", offsetof(MpegEncContext, quarter_sample), FF_OPT_TYPE_INT, {.i64 = 0}, 0, 1, 0},
2742  {"divx_packed", "divx style packed b frames", offsetof(MpegEncContext, divx_packed), FF_OPT_TYPE_INT, {.i64 = 0}, 0, 1, 0},
2743  {NULL}
2744 };
2745 
2746 static const AVClass mpeg4_class = {
2747  "MPEG4 Video Decoder",
2749  mpeg4_options,
2751 };
2752 
2753 static const AVClass mpeg4_vdpau_class = {
2754  "MPEG4 Video VDPAU Decoder",
2756  mpeg4_options,
2758 };
2759 
2761  .name = "mpeg4",
2762  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
2763  .type = AVMEDIA_TYPE_VIDEO,
2764  .id = AV_CODEC_ID_MPEG4,
2765  .priv_data_size = sizeof(Mpeg4DecContext),
2766  .init = decode_init,
2769  .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2772  .flush = ff_mpeg_flush,
2773  .max_lowres = 3,
2774  .pix_fmts = ff_h263_hwaccel_pixfmt_list_420,
2775  .profiles = NULL_IF_CONFIG_SMALL(mpeg4_video_profiles),
2776  .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg4_update_thread_context),
2777  .priv_class = &mpeg4_class,
2778 };
2779 
2780 
2781 #if CONFIG_MPEG4_VDPAU_DECODER
2782 AVCodec ff_mpeg4_vdpau_decoder = {
2783  .name = "mpeg4_vdpau",
2784  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 (VDPAU)"),
2785  .type = AVMEDIA_TYPE_VIDEO,
2786  .id = AV_CODEC_ID_MPEG4,
2787  .priv_data_size = sizeof(MpegEncContext),
2788  .init = decode_init,
2791  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2793  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_VDPAU_MPEG4,
2794  AV_PIX_FMT_NONE },
2795  .priv_class = &mpeg4_vdpau_class,
2796 };
2797 #endif