vp5.c
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1 /*
2  * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
3  *
4  * This file is part of Libav.
5  *
6  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
26 #include <stdlib.h>
27 #include <string.h>
28 
29 #include "avcodec.h"
30 #include "dsputil.h"
31 #include "get_bits.h"
32 
33 #include "vp56.h"
34 #include "vp56data.h"
35 #include "vp5data.h"
36 
37 
38 static int vp5_parse_header(VP56Context *s, const uint8_t *buf, int buf_size,
39  int *golden_frame)
40 {
41  VP56RangeCoder *c = &s->c;
42  int rows, cols;
43 
44  ff_vp56_init_range_decoder(&s->c, buf, buf_size);
46  vp56_rac_get(c);
49  {
50  vp56_rac_gets(c, 8);
51  if(vp56_rac_gets(c, 5) > 5)
52  return AVERROR_INVALIDDATA;
53  vp56_rac_gets(c, 2);
54  if (vp56_rac_get(c)) {
55  av_log(s->avctx, AV_LOG_ERROR, "interlacing not supported\n");
56  return AVERROR_PATCHWELCOME;
57  }
58  rows = vp56_rac_gets(c, 8); /* number of stored macroblock rows */
59  cols = vp56_rac_gets(c, 8); /* number of stored macroblock cols */
60  if (!rows || !cols) {
61  av_log(s->avctx, AV_LOG_ERROR, "Invalid size %dx%d\n",
62  cols << 4, rows << 4);
63  return AVERROR_INVALIDDATA;
64  }
65  vp56_rac_gets(c, 8); /* number of displayed macroblock rows */
66  vp56_rac_gets(c, 8); /* number of displayed macroblock cols */
67  vp56_rac_gets(c, 2);
68  if (!s->macroblocks || /* first frame */
69  16*cols != s->avctx->coded_width ||
70  16*rows != s->avctx->coded_height) {
71  avcodec_set_dimensions(s->avctx, 16*cols, 16*rows);
72  return VP56_SIZE_CHANGE;
73  }
74  } else if (!s->macroblocks)
75  return AVERROR_INVALIDDATA;
76  return 0;
77 }
78 
80 {
81  VP56RangeCoder *c = &s->c;
82  VP56Model *model = s->modelp;
83  int comp, di;
84 
85  for (comp=0; comp<2; comp++) {
86  int delta = 0;
87  if (vp56_rac_get_prob(c, model->vector_dct[comp])) {
88  int sign = vp56_rac_get_prob(c, model->vector_sig[comp]);
89  di = vp56_rac_get_prob(c, model->vector_pdi[comp][0]);
90  di |= vp56_rac_get_prob(c, model->vector_pdi[comp][1]) << 1;
92  model->vector_pdv[comp]);
93  delta = di | (delta << 2);
94  delta = (delta ^ -sign) + sign;
95  }
96  if (!comp)
97  vect->x = delta;
98  else
99  vect->y = delta;
100  }
101 }
102 
104 {
105  VP56RangeCoder *c = &s->c;
106  VP56Model *model = s->modelp;
107  int comp, node;
108 
109  for (comp=0; comp<2; comp++) {
110  if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][0]))
111  model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
112  if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][1]))
113  model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
114  if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][2]))
115  model->vector_pdi[comp][0] = vp56_rac_gets_nn(c, 7);
116  if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][3]))
117  model->vector_pdi[comp][1] = vp56_rac_gets_nn(c, 7);
118  }
119 
120  for (comp=0; comp<2; comp++)
121  for (node=0; node<7; node++)
122  if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][4 + node]))
123  model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
124 }
125 
127 {
128  VP56RangeCoder *c = &s->c;
129  VP56Model *model = s->modelp;
130  uint8_t def_prob[11];
131  int node, cg, ctx;
132  int ct; /* code type */
133  int pt; /* plane type (0 for Y, 1 for U or V) */
134 
135  memset(def_prob, 0x80, sizeof(def_prob));
136 
137  for (pt=0; pt<2; pt++)
138  for (node=0; node<11; node++)
139  if (vp56_rac_get_prob(c, vp5_dccv_pct[pt][node])) {
140  def_prob[node] = vp56_rac_gets_nn(c, 7);
141  model->coeff_dccv[pt][node] = def_prob[node];
142  } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
143  model->coeff_dccv[pt][node] = def_prob[node];
144  }
145 
146  for (ct=0; ct<3; ct++)
147  for (pt=0; pt<2; pt++)
148  for (cg=0; cg<6; cg++)
149  for (node=0; node<11; node++)
150  if (vp56_rac_get_prob(c, vp5_ract_pct[ct][pt][cg][node])) {
151  def_prob[node] = vp56_rac_gets_nn(c, 7);
152  model->coeff_ract[pt][ct][cg][node] = def_prob[node];
153  } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
154  model->coeff_ract[pt][ct][cg][node] = def_prob[node];
155  }
156 
157  /* coeff_dcct is a linear combination of coeff_dccv */
158  for (pt=0; pt<2; pt++)
159  for (ctx=0; ctx<36; ctx++)
160  for (node=0; node<5; node++)
161  model->coeff_dcct[pt][ctx][node] = av_clip(((model->coeff_dccv[pt][node] * vp5_dccv_lc[node][ctx][0] + 128) >> 8) + vp5_dccv_lc[node][ctx][1], 1, 254);
162 
163  /* coeff_acct is a linear combination of coeff_ract */
164  for (ct=0; ct<3; ct++)
165  for (pt=0; pt<2; pt++)
166  for (cg=0; cg<3; cg++)
167  for (ctx=0; ctx<6; ctx++)
168  for (node=0; node<5; node++)
169  model->coeff_acct[pt][ct][cg][ctx][node] = av_clip(((model->coeff_ract[pt][ct][cg][node] * vp5_ract_lc[ct][cg][node][ctx][0] + 128) >> 8) + vp5_ract_lc[ct][cg][node][ctx][1], 1, 254);
170  return 0;
171 }
172 
174 {
175  VP56RangeCoder *c = &s->c;
176  VP56Model *model = s->modelp;
177  uint8_t *permute = s->scantable.permutated;
178  uint8_t *model1, *model2;
179  int coeff, sign, coeff_idx;
180  int b, i, cg, idx, ctx, ctx_last;
181  int pt = 0; /* plane type (0 for Y, 1 for U or V) */
182 
183  for (b=0; b<6; b++) {
184  int ct = 1; /* code type */
185 
186  if (b > 3) pt = 1;
187 
188  ctx = 6*s->coeff_ctx[vp56_b6to4[b]][0]
190  model1 = model->coeff_dccv[pt];
191  model2 = model->coeff_dcct[pt][ctx];
192 
193  coeff_idx = 0;
194  for (;;) {
195  if (vp56_rac_get_prob(c, model2[0])) {
196  if (vp56_rac_get_prob(c, model2[2])) {
197  if (vp56_rac_get_prob(c, model2[3])) {
198  s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 4;
199  idx = vp56_rac_get_tree(c, vp56_pc_tree, model1);
200  sign = vp56_rac_get(c);
201  coeff = vp56_coeff_bias[idx+5];
202  for (i=vp56_coeff_bit_length[idx]; i>=0; i--)
203  coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i;
204  } else {
205  if (vp56_rac_get_prob(c, model2[4])) {
206  coeff = 3 + vp56_rac_get_prob(c, model1[5]);
207  s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 3;
208  } else {
209  coeff = 2;
210  s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 2;
211  }
212  sign = vp56_rac_get(c);
213  }
214  ct = 2;
215  } else {
216  ct = 1;
217  s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 1;
218  sign = vp56_rac_get(c);
219  coeff = 1;
220  }
221  coeff = (coeff ^ -sign) + sign;
222  if (coeff_idx)
223  coeff *= s->dequant_ac;
224  s->block_coeff[b][permute[coeff_idx]] = coeff;
225  } else {
226  if (ct && !vp56_rac_get_prob(c, model2[1]))
227  break;
228  ct = 0;
229  s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 0;
230  }
231  coeff_idx++;
232  if (coeff_idx >= 64)
233  break;
234 
235  cg = vp5_coeff_groups[coeff_idx];
236  ctx = s->coeff_ctx[vp56_b6to4[b]][coeff_idx];
237  model1 = model->coeff_ract[pt][ct][cg];
238  model2 = cg > 2 ? model1 : model->coeff_acct[pt][ct][cg][ctx];
239  }
240 
241  ctx_last = FFMIN(s->coeff_ctx_last[vp56_b6to4[b]], 24);
242  s->coeff_ctx_last[vp56_b6to4[b]] = coeff_idx;
243  if (coeff_idx < ctx_last)
244  for (i=coeff_idx; i<=ctx_last; i++)
245  s->coeff_ctx[vp56_b6to4[b]][i] = 5;
247  }
248 }
249 
251 {
252  VP56Model *model = s->modelp;
253  int i;
254 
255  for (i=0; i<2; i++) {
256  model->vector_sig[i] = 0x80;
257  model->vector_dct[i] = 0x80;
258  model->vector_pdi[i][0] = 0x55;
259  model->vector_pdi[i][1] = 0x80;
260  }
261  memcpy(model->mb_types_stats, vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
262  memset(model->vector_pdv, 0x80, sizeof(model->vector_pdv));
263 }
264 
266 {
267  VP56Context *s = avctx->priv_data;
268 
269  ff_vp56_init(avctx, 1, 0);
277 
278  return 0;
279 }
280 
282  .name = "vp5",
283  .type = AVMEDIA_TYPE_VIDEO,
284  .id = CODEC_ID_VP5,
285  .priv_data_size = sizeof(VP56Context),
287  .close = ff_vp56_free,
289  .capabilities = CODEC_CAP_DR1,
290  .long_name = NULL_IF_CONFIG_SMALL("On2 VP5"),
291 };