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vp5.c
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1 /*
2  * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
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 /**
22  * @file
23  * VP5 compatible video decoder
24  */
25 
26 #include <stdlib.h>
27 #include <string.h>
28 
29 #include "avcodec.h"
30 #include "get_bits.h"
31 #include "internal.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 {
40  VP56RangeCoder *c = &s->c;
41  int rows, cols;
42 
43  ff_vp56_init_range_decoder(&s->c, buf, buf_size);
44  s->frames[VP56_FRAME_CURRENT]->key_frame = !vp56_rac_get(c);
45  vp56_rac_get(c);
46  ff_vp56_init_dequant(s, vp56_rac_gets(c, 6));
47  if (s->frames[VP56_FRAME_CURRENT]->key_frame)
48  {
49  vp56_rac_gets(c, 8);
50  if(vp56_rac_gets(c, 5) > 5)
51  return AVERROR_INVALIDDATA;
52  vp56_rac_gets(c, 2);
53  if (vp56_rac_get(c)) {
54  av_log(s->avctx, AV_LOG_ERROR, "interlacing not supported\n");
55  return AVERROR_PATCHWELCOME;
56  }
57  rows = vp56_rac_gets(c, 8); /* number of stored macroblock rows */
58  cols = vp56_rac_gets(c, 8); /* number of stored macroblock cols */
59  if (!rows || !cols) {
60  av_log(s->avctx, AV_LOG_ERROR, "Invalid size %dx%d\n",
61  cols << 4, rows << 4);
62  return AVERROR_INVALIDDATA;
63  }
64  vp56_rac_gets(c, 8); /* number of displayed macroblock rows */
65  vp56_rac_gets(c, 8); /* number of displayed macroblock cols */
66  vp56_rac_gets(c, 2);
67  if (!s->macroblocks || /* first frame */
68  16*cols != s->avctx->coded_width ||
69  16*rows != s->avctx->coded_height) {
70  int ret = ff_set_dimensions(s->avctx, 16 * cols, 16 * rows);
71  if (ret < 0)
72  return ret;
73  return VP56_SIZE_CHANGE;
74  }
75  } else if (!s->macroblocks)
76  return AVERROR_INVALIDDATA;
77  return 0;
78 }
79 
80 static void vp5_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
81 {
82  VP56RangeCoder *c = &s->c;
83  VP56Model *model = s->modelp;
84  int comp, di;
85 
86  for (comp=0; comp<2; comp++) {
87  int delta = 0;
88  if (vp56_rac_get_prob_branchy(c, model->vector_dct[comp])) {
89  int sign = vp56_rac_get_prob(c, model->vector_sig[comp]);
90  di = vp56_rac_get_prob(c, model->vector_pdi[comp][0]);
91  di |= vp56_rac_get_prob(c, model->vector_pdi[comp][1]) << 1;
92  delta = vp56_rac_get_tree(c, ff_vp56_pva_tree,
93  model->vector_pdv[comp]);
94  delta = di | (delta << 2);
95  delta = (delta ^ -sign) + sign;
96  }
97  if (!comp)
98  vect->x = delta;
99  else
100  vect->y = delta;
101  }
102 }
103 
104 static void vp5_parse_vector_models(VP56Context *s)
105 {
106  VP56RangeCoder *c = &s->c;
107  VP56Model *model = s->modelp;
108  int comp, node;
109 
110  for (comp=0; comp<2; comp++) {
111  if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][0]))
112  model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
113  if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][1]))
114  model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
115  if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][2]))
116  model->vector_pdi[comp][0] = vp56_rac_gets_nn(c, 7);
117  if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][3]))
118  model->vector_pdi[comp][1] = vp56_rac_gets_nn(c, 7);
119  }
120 
121  for (comp=0; comp<2; comp++)
122  for (node=0; node<7; node++)
123  if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][4 + node]))
124  model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
125 }
126 
127 static int vp5_parse_coeff_models(VP56Context *s)
128 {
129  VP56RangeCoder *c = &s->c;
130  VP56Model *model = s->modelp;
131  uint8_t def_prob[11];
132  int node, cg, ctx;
133  int ct; /* code type */
134  int pt; /* plane type (0 for Y, 1 for U or V) */
135 
136  memset(def_prob, 0x80, sizeof(def_prob));
137 
138  for (pt=0; pt<2; pt++)
139  for (node=0; node<11; node++)
140  if (vp56_rac_get_prob_branchy(c, vp5_dccv_pct[pt][node])) {
141  def_prob[node] = vp56_rac_gets_nn(c, 7);
142  model->coeff_dccv[pt][node] = def_prob[node];
143  } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
144  model->coeff_dccv[pt][node] = def_prob[node];
145  }
146 
147  for (ct=0; ct<3; ct++)
148  for (pt=0; pt<2; pt++)
149  for (cg=0; cg<6; cg++)
150  for (node=0; node<11; node++)
151  if (vp56_rac_get_prob_branchy(c, vp5_ract_pct[ct][pt][cg][node])) {
152  def_prob[node] = vp56_rac_gets_nn(c, 7);
153  model->coeff_ract[pt][ct][cg][node] = def_prob[node];
154  } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
155  model->coeff_ract[pt][ct][cg][node] = def_prob[node];
156  }
157 
158  /* coeff_dcct is a linear combination of coeff_dccv */
159  for (pt=0; pt<2; pt++)
160  for (ctx=0; ctx<36; ctx++)
161  for (node=0; node<5; node++)
162  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);
163 
164  /* coeff_acct is a linear combination of coeff_ract */
165  for (ct=0; ct<3; ct++)
166  for (pt=0; pt<2; pt++)
167  for (cg=0; cg<3; cg++)
168  for (ctx=0; ctx<6; ctx++)
169  for (node=0; node<5; node++)
170  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);
171  return 0;
172 }
173 
174 static void vp5_parse_coeff(VP56Context *s)
175 {
176  VP56RangeCoder *c = &s->c;
177  VP56Model *model = s->modelp;
178  uint8_t *permute = s->idct_scantable;
179  uint8_t *model1, *model2;
180  int coeff, sign, coeff_idx;
181  int b, i, cg, idx, ctx, ctx_last;
182  int pt = 0; /* plane type (0 for Y, 1 for U or V) */
183 
184  for (b=0; b<6; b++) {
185  int ct = 1; /* code type */
186 
187  if (b > 3) pt = 1;
188 
189  ctx = 6*s->coeff_ctx[ff_vp56_b6to4[b]][0]
190  + s->above_blocks[s->above_block_idx[b]].not_null_dc;
191  model1 = model->coeff_dccv[pt];
192  model2 = model->coeff_dcct[pt][ctx];
193 
194  coeff_idx = 0;
195  for (;;) {
196  if (vp56_rac_get_prob_branchy(c, model2[0])) {
197  if (vp56_rac_get_prob_branchy(c, model2[2])) {
198  if (vp56_rac_get_prob_branchy(c, model2[3])) {
199  s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 4;
200  idx = vp56_rac_get_tree(c, ff_vp56_pc_tree, model1);
201  sign = vp56_rac_get(c);
202  coeff = ff_vp56_coeff_bias[idx+5];
203  for (i=ff_vp56_coeff_bit_length[idx]; i>=0; i--)
204  coeff += vp56_rac_get_prob(c, ff_vp56_coeff_parse_table[idx][i]) << i;
205  } else {
206  if (vp56_rac_get_prob_branchy(c, model2[4])) {
207  coeff = 3 + vp56_rac_get_prob(c, model1[5]);
208  s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 3;
209  } else {
210  coeff = 2;
211  s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 2;
212  }
213  sign = vp56_rac_get(c);
214  }
215  ct = 2;
216  } else {
217  ct = 1;
218  s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 1;
219  sign = vp56_rac_get(c);
220  coeff = 1;
221  }
222  coeff = (coeff ^ -sign) + sign;
223  if (coeff_idx)
224  coeff *= s->dequant_ac;
225  s->block_coeff[b][permute[coeff_idx]] = coeff;
226  } else {
227  if (ct && !vp56_rac_get_prob_branchy(c, model2[1]))
228  break;
229  ct = 0;
230  s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 0;
231  }
232  coeff_idx++;
233  if (coeff_idx >= 64)
234  break;
235 
236  cg = vp5_coeff_groups[coeff_idx];
237  ctx = s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx];
238  model1 = model->coeff_ract[pt][ct][cg];
239  model2 = cg > 2 ? model1 : model->coeff_acct[pt][ct][cg][ctx];
240  }
241 
242  ctx_last = FFMIN(s->coeff_ctx_last[ff_vp56_b6to4[b]], 24);
243  s->coeff_ctx_last[ff_vp56_b6to4[b]] = coeff_idx;
244  if (coeff_idx < ctx_last)
245  for (i=coeff_idx; i<=ctx_last; i++)
246  s->coeff_ctx[ff_vp56_b6to4[b]][i] = 5;
247  s->above_blocks[s->above_block_idx[b]].not_null_dc = s->coeff_ctx[ff_vp56_b6to4[b]][0];
248  }
249 }
250 
251 static void vp5_default_models_init(VP56Context *s)
252 {
253  VP56Model *model = s->modelp;
254  int i;
255 
256  for (i=0; i<2; i++) {
257  model->vector_sig[i] = 0x80;
258  model->vector_dct[i] = 0x80;
259  model->vector_pdi[i][0] = 0x55;
260  model->vector_pdi[i][1] = 0x80;
261  }
262  memcpy(model->mb_types_stats, ff_vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
263  memset(model->vector_pdv, 0x80, sizeof(model->vector_pdv));
264 }
265 
266 static av_cold int vp5_decode_init(AVCodecContext *avctx)
267 {
268  VP56Context *s = avctx->priv_data;
269  int ret;
270 
271  if ((ret = ff_vp56_init(avctx, 1, 0)) < 0)
272  return ret;
273  s->vp56_coord_div = vp5_coord_div;
274  s->parse_vector_adjustment = vp5_parse_vector_adjustment;
275  s->parse_coeff = vp5_parse_coeff;
276  s->default_models_init = vp5_default_models_init;
277  s->parse_vector_models = vp5_parse_vector_models;
278  s->parse_coeff_models = vp5_parse_coeff_models;
279  s->parse_header = vp5_parse_header;
280 
281  return 0;
282 }
283 
284 AVCodec ff_vp5_decoder = {
285  .name = "vp5",
286  .long_name = NULL_IF_CONFIG_SMALL("On2 VP5"),
287  .type = AVMEDIA_TYPE_VIDEO,
288  .id = AV_CODEC_ID_VP5,
289  .priv_data_size = sizeof(VP56Context),
290  .init = vp5_decode_init,
291  .close = ff_vp56_free,
292  .decode = ff_vp56_decode_frame,
293  .capabilities = CODEC_CAP_DR1,
294 };
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