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wmv2dec.c
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1 /*
2  * Copyright (c) 2002 The FFmpeg Project
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "avcodec.h"
22 #include "h263.h"
23 #include "intrax8.h"
24 #include "mathops.h"
25 #include "mpegutils.h"
26 #include "mpegvideo.h"
27 #include "msmpeg4.h"
28 #include "msmpeg4data.h"
29 #include "wmv2.h"
30 
31 
32 static void parse_mb_skip(Wmv2Context *w)
33 {
34  int mb_x, mb_y;
35  MpegEncContext *const s = &w->s;
36  uint32_t *const mb_type = s->current_picture_ptr->mb_type;
37 
38  w->skip_type = get_bits(&s->gb, 2);
39  switch (w->skip_type) {
40  case SKIP_TYPE_NONE:
41  for (mb_y = 0; mb_y < s->mb_height; mb_y++)
42  for (mb_x = 0; mb_x < s->mb_width; mb_x++)
43  mb_type[mb_y * s->mb_stride + mb_x] =
45  break;
46  case SKIP_TYPE_MPEG:
47  for (mb_y = 0; mb_y < s->mb_height; mb_y++)
48  for (mb_x = 0; mb_x < s->mb_width; mb_x++)
49  mb_type[mb_y * s->mb_stride + mb_x] =
51  break;
52  case SKIP_TYPE_ROW:
53  for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
54  if (get_bits1(&s->gb)) {
55  for (mb_x = 0; mb_x < s->mb_width; mb_x++)
56  mb_type[mb_y * s->mb_stride + mb_x] =
58  } else {
59  for (mb_x = 0; mb_x < s->mb_width; mb_x++)
60  mb_type[mb_y * s->mb_stride + mb_x] =
62  }
63  }
64  break;
65  case SKIP_TYPE_COL:
66  for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
67  if (get_bits1(&s->gb)) {
68  for (mb_y = 0; mb_y < s->mb_height; mb_y++)
69  mb_type[mb_y * s->mb_stride + mb_x] =
71  } else {
72  for (mb_y = 0; mb_y < s->mb_height; mb_y++)
73  mb_type[mb_y * s->mb_stride + mb_x] =
75  }
76  }
77  break;
78  }
79 }
80 
82 {
83  MpegEncContext *const s = &w->s;
84  GetBitContext gb;
85  int fps;
86  int code;
87 
88  if (s->avctx->extradata_size < 4)
89  return -1;
90 
91  init_get_bits(&gb, s->avctx->extradata, 32);
92 
93  fps = get_bits(&gb, 5);
94  s->bit_rate = get_bits(&gb, 11) * 1024;
95  w->mspel_bit = get_bits1(&gb);
96  s->loop_filter = get_bits1(&gb);
97  w->abt_flag = get_bits1(&gb);
98  w->j_type_bit = get_bits1(&gb);
99  w->top_left_mv_flag = get_bits1(&gb);
100  w->per_mb_rl_bit = get_bits1(&gb);
101  code = get_bits(&gb, 3);
102 
103  if (code == 0)
104  return -1;
105 
106  s->slice_height = s->mb_height / code;
107 
108  if (s->avctx->debug & FF_DEBUG_PICT_INFO)
110  "fps:%d, br:%d, qpbit:%d, abt_flag:%d, j_type_bit:%d, "
111  "tl_mv_flag:%d, mbrl_bit:%d, code:%d, loop_filter:%d, "
112  "slices:%d\n",
113  fps, s->bit_rate, w->mspel_bit, w->abt_flag, w->j_type_bit,
114  w->top_left_mv_flag, w->per_mb_rl_bit, code, s->loop_filter,
115  code);
116  return 0;
117 }
118 
120 {
121  Wmv2Context *const w = (Wmv2Context *) s;
122  int code;
123 
124  if (s->picture_number == 0)
126 
127  s->pict_type = get_bits1(&s->gb) + 1;
128  if (s->pict_type == AV_PICTURE_TYPE_I) {
129  code = get_bits(&s->gb, 7);
130  av_log(s->avctx, AV_LOG_DEBUG, "I7:%X/\n", code);
131  }
132  s->chroma_qscale = s->qscale = get_bits(&s->gb, 5);
133  if (s->qscale <= 0)
134  return -1;
135 
136  return 0;
137 }
138 
140 {
141  Wmv2Context *const w = (Wmv2Context *) s;
142 
143  if (s->pict_type == AV_PICTURE_TYPE_I) {
144  if (w->j_type_bit)
145  w->j_type = get_bits1(&s->gb);
146  else
147  w->j_type = 0; // FIXME check
148 
149  if (!w->j_type) {
150  if (w->per_mb_rl_bit)
151  s->per_mb_rl_table = get_bits1(&s->gb);
152  else
153  s->per_mb_rl_table = 0;
154 
155  if (!s->per_mb_rl_table) {
157  s->rl_table_index = decode012(&s->gb);
158  }
159 
160  s->dc_table_index = get_bits1(&s->gb);
161  }
162  s->inter_intra_pred = 0;
163  s->no_rounding = 1;
164  if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
166  "qscale:%d rlc:%d rl:%d dc:%d mbrl:%d j_type:%d \n",
169  }
170  } else {
171  int cbp_index;
172  w->j_type = 0;
173 
174  parse_mb_skip(w);
175  cbp_index = decode012(&s->gb);
176  if (s->qscale <= 10) {
177  int map[3] = { 0, 2, 1 };
178  w->cbp_table_index = map[cbp_index];
179  } else if (s->qscale <= 20) {
180  int map[3] = { 1, 0, 2 };
181  w->cbp_table_index = map[cbp_index];
182  } else {
183  int map[3] = {2,1,0};
184  w->cbp_table_index = map[cbp_index];
185  }
186 
187  if (w->mspel_bit)
188  s->mspel = get_bits1(&s->gb);
189  else
190  s->mspel = 0; // FIXME check
191 
192  if (w->abt_flag) {
193  w->per_mb_abt = get_bits1(&s->gb) ^ 1;
194  if (!w->per_mb_abt)
195  w->abt_type = decode012(&s->gb);
196  }
197 
198  if (w->per_mb_rl_bit)
199  s->per_mb_rl_table = get_bits1(&s->gb);
200  else
201  s->per_mb_rl_table = 0;
202 
203  if (!s->per_mb_rl_table) {
204  s->rl_table_index = decode012(&s->gb);
206  }
207 
208  s->dc_table_index = get_bits1(&s->gb);
209  s->mv_table_index = get_bits1(&s->gb);
210 
211  s->inter_intra_pred = 0; // (s->width * s->height < 320 * 240 && s->bit_rate <= II_BITRATE);
212  s->no_rounding ^= 1;
213 
214  if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
216  "rl:%d rlc:%d dc:%d mv:%d mbrl:%d qp:%d mspel:%d "
217  "per_mb_abt:%d abt_type:%d cbp:%d ii:%d\n",
220  s->per_mb_rl_table, s->qscale, s->mspel,
222  s->inter_intra_pred);
223  }
224  }
225  s->esc3_level_length = 0;
226  s->esc3_run_length = 0;
227  s->picture_number++; // FIXME ?
228 
229  if (w->j_type) {
230  ff_intrax8_decode_picture(&w->x8, 2 * s->qscale, (s->qscale - 1) | 1);
231  return 1;
232  }
233 
234  return 0;
235 }
236 
237 static inline int wmv2_decode_motion(Wmv2Context *w, int *mx_ptr, int *my_ptr)
238 {
239  MpegEncContext *const s = &w->s;
240  int ret;
241 
242  ret = ff_msmpeg4_decode_motion(s, mx_ptr, my_ptr);
243 
244  if (ret < 0)
245  return -1;
246 
247  if ((((*mx_ptr) | (*my_ptr)) & 1) && s->mspel)
248  w->hshift = get_bits1(&s->gb);
249  else
250  w->hshift = 0;
251 
252  return 0;
253 }
254 
255 static int16_t *wmv2_pred_motion(Wmv2Context *w, int *px, int *py)
256 {
257  MpegEncContext *const s = &w->s;
258  int xy, wrap, diff, type;
259  int16_t *A, *B, *C, *mot_val;
260 
261  wrap = s->b8_stride;
262  xy = s->block_index[0];
263 
264  mot_val = s->current_picture.motion_val[0][xy];
265 
266  A = s->current_picture.motion_val[0][xy - 1];
267  B = s->current_picture.motion_val[0][xy - wrap];
268  C = s->current_picture.motion_val[0][xy + 2 - wrap];
269 
270  if (s->mb_x && !s->first_slice_line && !s->mspel && w->top_left_mv_flag)
271  diff = FFMAX(FFABS(A[0] - B[0]), FFABS(A[1] - B[1]));
272  else
273  diff = 0;
274 
275  if (diff >= 8)
276  type = get_bits1(&s->gb);
277  else
278  type = 2;
279 
280  if (type == 0) {
281  *px = A[0];
282  *py = A[1];
283  } else if (type == 1) {
284  *px = B[0];
285  *py = B[1];
286  } else {
287  /* special case for first (slice) line */
288  if (s->first_slice_line) {
289  *px = A[0];
290  *py = A[1];
291  } else {
292  *px = mid_pred(A[0], B[0], C[0]);
293  *py = mid_pred(A[1], B[1], C[1]);
294  }
295  }
296 
297  return mot_val;
298 }
299 
300 static inline int wmv2_decode_inter_block(Wmv2Context *w, int16_t *block,
301  int n, int cbp)
302 {
303  MpegEncContext *const s = &w->s;
304  static const int sub_cbp_table[3] = { 2, 3, 1 };
305  int sub_cbp;
306 
307  if (!cbp) {
308  s->block_last_index[n] = -1;
309  return 0;
310  }
311 
312  if (w->per_block_abt)
313  w->abt_type = decode012(&s->gb);
314  w->abt_type_table[n] = w->abt_type;
315 
316  if (w->abt_type) {
317 // const uint8_t *scantable = w->abt_scantable[w->abt_type - 1].permutated;
318  const uint8_t *scantable = w->abt_scantable[w->abt_type - 1].scantable;
319 // const uint8_t *scantable = w->abt_type - 1 ? w->abt_scantable[1].permutated : w->abt_scantable[0].scantable;
320 
321  sub_cbp = sub_cbp_table[decode012(&s->gb)];
322 
323  if (sub_cbp & 1)
324  if (ff_msmpeg4_decode_block(s, block, n, 1, scantable) < 0)
325  return -1;
326 
327  if (sub_cbp & 2)
328  if (ff_msmpeg4_decode_block(s, w->abt_block2[n], n, 1, scantable) < 0)
329  return -1;
330 
331  s->block_last_index[n] = 63;
332 
333  return 0;
334  } else {
335  return ff_msmpeg4_decode_block(s, block, n, 1,
337  }
338 }
339 
341 {
342  Wmv2Context *const w = (Wmv2Context *) s;
343  int cbp, code, i;
344  uint8_t *coded_val;
345 
346  if (w->j_type)
347  return 0;
348 
349  if (s->pict_type == AV_PICTURE_TYPE_P) {
350  if (IS_SKIP(s->current_picture.mb_type[s->mb_y * s->mb_stride + s->mb_x])) {
351  /* skip mb */
352  s->mb_intra = 0;
353  for (i = 0; i < 6; i++)
354  s->block_last_index[i] = -1;
355  s->mv_dir = MV_DIR_FORWARD;
356  s->mv_type = MV_TYPE_16X16;
357  s->mv[0][0][0] = 0;
358  s->mv[0][0][1] = 0;
359  s->mb_skipped = 1;
360  w->hshift = 0;
361  return 0;
362  }
363 
366  if (code < 0)
367  return -1;
368  s->mb_intra = (~code & 0x40) >> 6;
369 
370  cbp = code & 0x3f;
371  } else {
372  s->mb_intra = 1;
374  if (code < 0) {
376  "II-cbp illegal at %d %d\n", s->mb_x, s->mb_y);
377  return -1;
378  }
379  /* predict coded block pattern */
380  cbp = 0;
381  for (i = 0; i < 6; i++) {
382  int val = ((code >> (5 - i)) & 1);
383  if (i < 4) {
384  int pred = ff_msmpeg4_coded_block_pred(s, i, &coded_val);
385  val = val ^ pred;
386  *coded_val = val;
387  }
388  cbp |= val << (5 - i);
389  }
390  }
391 
392  if (!s->mb_intra) {
393  int mx, my;
394  wmv2_pred_motion(w, &mx, &my);
395 
396  if (cbp) {
397  s->bdsp.clear_blocks(s->block[0]);
398  if (s->per_mb_rl_table) {
399  s->rl_table_index = decode012(&s->gb);
401  }
402 
403  if (w->abt_flag && w->per_mb_abt) {
404  w->per_block_abt = get_bits1(&s->gb);
405  if (!w->per_block_abt)
406  w->abt_type = decode012(&s->gb);
407  } else
408  w->per_block_abt = 0;
409  }
410 
411  if (wmv2_decode_motion(w, &mx, &my) < 0)
412  return -1;
413 
414  s->mv_dir = MV_DIR_FORWARD;
415  s->mv_type = MV_TYPE_16X16;
416  s->mv[0][0][0] = mx;
417  s->mv[0][0][1] = my;
418 
419  for (i = 0; i < 6; i++) {
420  if (wmv2_decode_inter_block(w, block[i], i, (cbp >> (5 - i)) & 1) < 0) {
422  "\nerror while decoding inter block: %d x %d (%d)\n",
423  s->mb_x, s->mb_y, i);
424  return -1;
425  }
426  }
427  } else {
428  if (s->pict_type == AV_PICTURE_TYPE_P)
429  av_dlog(s->avctx, "%d%d ", s->inter_intra_pred, cbp);
430  av_dlog(s->avctx, "I at %d %d %d %06X\n", s->mb_x, s->mb_y,
431  ((cbp & 3) ? 1 : 0) + ((cbp & 0x3C) ? 2 : 0),
432  show_bits(&s->gb, 24));
433  s->ac_pred = get_bits1(&s->gb);
434  if (s->inter_intra_pred) {
437  av_dlog(s->avctx, "%d%d %d %d/",
438  s->ac_pred, s->h263_aic_dir, s->mb_x, s->mb_y);
439  }
440  if (s->per_mb_rl_table && cbp) {
441  s->rl_table_index = decode012(&s->gb);
443  }
444 
445  s->bdsp.clear_blocks(s->block[0]);
446  for (i = 0; i < 6; i++) {
447  if (ff_msmpeg4_decode_block(s, block[i], i, (cbp >> (5 - i)) & 1, NULL) < 0) {
449  "\nerror while decoding intra block: %d x %d (%d)\n",
450  s->mb_x, s->mb_y, i);
451  return -1;
452  }
453  }
454  }
455 
456  return 0;
457 }
458 
460 {
461  Wmv2Context *const w = avctx->priv_data;
462 
463  avctx->flags |= CODEC_FLAG_EMU_EDGE;
464 
465  if (ff_msmpeg4_decode_init(avctx) < 0)
466  return -1;
467 
469 
470  ff_intrax8_common_init(&w->x8, &w->s);
471 
472  return 0;
473 }
474 
476 {
477  Wmv2Context *w = avctx->priv_data;
478 
480  return ff_h263_decode_end(avctx);
481 }
482 
484  .name = "wmv2",
485  .long_name = NULL_IF_CONFIG_SMALL("Windows Media Video 8"),
486  .type = AVMEDIA_TYPE_VIDEO,
487  .id = AV_CODEC_ID_WMV2,
488  .priv_data_size = sizeof(Wmv2Context),
492  .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
493  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
494  AV_PIX_FMT_NONE },
495 };