const
[libav.git] / libavcodec / vp5.c
1 /**
2 * @file vp5.c
3 * VP5 compatible video decoder
4 *
5 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24 #include <stdlib.h>
25 #include <string.h>
26
27 #include "avcodec.h"
28 #include "dsputil.h"
29 #include "bitstream.h"
30 #include "mpegvideo.h"
31
32 #include "vp56.h"
33 #include "vp56data.h"
34 #include "vp5data.h"
35
36
37 static int vp5_parse_header(vp56_context_t *s, const uint8_t *buf, int buf_size,
38 int *golden_frame)
39 {
40 vp56_range_coder_t *c = &s->c;
41 int rows, cols;
42
43 vp56_init_range_decoder(&s->c, buf, buf_size);
44 s->framep[VP56_FRAME_CURRENT]->key_frame = !vp56_rac_get(c);
45 vp56_rac_get(c);
46 vp56_init_dequant(s, vp56_rac_gets(c, 6));
47 if (s->framep[VP56_FRAME_CURRENT]->key_frame)
48 {
49 vp56_rac_gets(c, 8);
50 if(vp56_rac_gets(c, 5) > 5)
51 return 0;
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 0;
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 vp56_rac_gets(c, 8); /* number of displayed macroblock rows */
60 vp56_rac_gets(c, 8); /* number of displayed macroblock cols */
61 vp56_rac_gets(c, 2);
62 if (16*cols != s->avctx->coded_width ||
63 16*rows != s->avctx->coded_height) {
64 avcodec_set_dimensions(s->avctx, 16*cols, 16*rows);
65 return 2;
66 }
67 }
68 return 1;
69 }
70
71 /* Gives very similar result than the vp6 version except in a few cases */
72 static int vp5_adjust(int v, int t)
73 {
74 int s2, s1 = v >> 31;
75 v ^= s1;
76 v -= s1;
77 v *= v < 2*t;
78 v -= t;
79 s2 = v >> 31;
80 v ^= s2;
81 v -= s2;
82 v = t - v;
83 v += s1;
84 v ^= s1;
85 return v;
86 }
87
88 static void vp5_parse_vector_adjustment(vp56_context_t *s, vp56_mv_t *vect)
89 {
90 vp56_range_coder_t *c = &s->c;
91 vp56_model_t *model = s->modelp;
92 int comp, di;
93
94 for (comp=0; comp<2; comp++) {
95 int delta = 0;
96 if (vp56_rac_get_prob(c, model->vector_dct[comp])) {
97 int sign = vp56_rac_get_prob(c, model->vector_sig[comp]);
98 di = vp56_rac_get_prob(c, model->vector_pdi[comp][0]);
99 di |= vp56_rac_get_prob(c, model->vector_pdi[comp][1]) << 1;
100 delta = vp56_rac_get_tree(c, vp56_pva_tree,
101 model->vector_pdv[comp]);
102 delta = di | (delta << 2);
103 delta = (delta ^ -sign) + sign;
104 }
105 if (!comp)
106 vect->x = delta;
107 else
108 vect->y = delta;
109 }
110 }
111
112 static void vp5_parse_vector_models(vp56_context_t *s)
113 {
114 vp56_range_coder_t *c = &s->c;
115 vp56_model_t *model = s->modelp;
116 int comp, node;
117
118 for (comp=0; comp<2; comp++) {
119 if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][0]))
120 model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
121 if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][1]))
122 model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
123 if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][2]))
124 model->vector_pdi[comp][0] = vp56_rac_gets_nn(c, 7);
125 if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][3]))
126 model->vector_pdi[comp][1] = vp56_rac_gets_nn(c, 7);
127 }
128
129 for (comp=0; comp<2; comp++)
130 for (node=0; node<7; node++)
131 if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][4 + node]))
132 model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
133 }
134
135 static void vp5_parse_coeff_models(vp56_context_t *s)
136 {
137 vp56_range_coder_t *c = &s->c;
138 vp56_model_t *model = s->modelp;
139 uint8_t def_prob[11];
140 int node, cg, ctx;
141 int ct; /* code type */
142 int pt; /* plane type (0 for Y, 1 for U or V) */
143
144 memset(def_prob, 0x80, sizeof(def_prob));
145
146 for (pt=0; pt<2; pt++)
147 for (node=0; node<11; node++)
148 if (vp56_rac_get_prob(c, vp5_dccv_pct[pt][node])) {
149 def_prob[node] = vp56_rac_gets_nn(c, 7);
150 model->coeff_dccv[pt][node] = def_prob[node];
151 } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
152 model->coeff_dccv[pt][node] = def_prob[node];
153 }
154
155 for (ct=0; ct<3; ct++)
156 for (pt=0; pt<2; pt++)
157 for (cg=0; cg<6; cg++)
158 for (node=0; node<11; node++)
159 if (vp56_rac_get_prob(c, vp5_ract_pct[ct][pt][cg][node])) {
160 def_prob[node] = vp56_rac_gets_nn(c, 7);
161 model->coeff_ract[pt][ct][cg][node] = def_prob[node];
162 } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
163 model->coeff_ract[pt][ct][cg][node] = def_prob[node];
164 }
165
166 /* coeff_dcct is a linear combination of coeff_dccv */
167 for (pt=0; pt<2; pt++)
168 for (ctx=0; ctx<36; ctx++)
169 for (node=0; node<5; node++)
170 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);
171
172 /* coeff_acct is a linear combination of coeff_ract */
173 for (ct=0; ct<3; ct++)
174 for (pt=0; pt<2; pt++)
175 for (cg=0; cg<3; cg++)
176 for (ctx=0; ctx<6; ctx++)
177 for (node=0; node<5; node++)
178 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);
179 }
180
181 static void vp5_parse_coeff(vp56_context_t *s)
182 {
183 vp56_range_coder_t *c = &s->c;
184 vp56_model_t *model = s->modelp;
185 uint8_t *permute = s->scantable.permutated;
186 uint8_t *model1, *model2;
187 int coeff, sign, coeff_idx;
188 int b, i, cg, idx, ctx, ctx_last;
189 int pt = 0; /* plane type (0 for Y, 1 for U or V) */
190
191 for (b=0; b<6; b++) {
192 int ct = 1; /* code type */
193
194 if (b > 3) pt = 1;
195
196 ctx = 6*s->coeff_ctx[vp56_b6to4[b]][0]
197 + s->above_blocks[s->above_block_idx[b]].not_null_dc;
198 model1 = model->coeff_dccv[pt];
199 model2 = model->coeff_dcct[pt][ctx];
200
201 for (coeff_idx=0; coeff_idx<64; ) {
202 if (vp56_rac_get_prob(c, model2[0])) {
203 if (vp56_rac_get_prob(c, model2[2])) {
204 if (vp56_rac_get_prob(c, model2[3])) {
205 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 4;
206 idx = vp56_rac_get_tree(c, vp56_pc_tree, model1);
207 sign = vp56_rac_get(c);
208 coeff = vp56_coeff_bias[idx+5];
209 for (i=vp56_coeff_bit_length[idx]; i>=0; i--)
210 coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i;
211 } else {
212 if (vp56_rac_get_prob(c, model2[4])) {
213 coeff = 3 + vp56_rac_get_prob(c, model1[5]);
214 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 3;
215 } else {
216 coeff = 2;
217 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 2;
218 }
219 sign = vp56_rac_get(c);
220 }
221 ct = 2;
222 } else {
223 ct = 1;
224 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 1;
225 sign = vp56_rac_get(c);
226 coeff = 1;
227 }
228 coeff = (coeff ^ -sign) + sign;
229 if (coeff_idx)
230 coeff *= s->dequant_ac;
231 s->block_coeff[b][permute[coeff_idx]] = coeff;
232 } else {
233 if (ct && !vp56_rac_get_prob(c, model2[1]))
234 break;
235 ct = 0;
236 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 0;
237 }
238
239 cg = vp5_coeff_groups[++coeff_idx];
240 ctx = s->coeff_ctx[vp56_b6to4[b]][coeff_idx];
241 model1 = model->coeff_ract[pt][ct][cg];
242 model2 = cg > 2 ? model1 : model->coeff_acct[pt][ct][cg][ctx];
243 }
244
245 ctx_last = FFMIN(s->coeff_ctx_last[vp56_b6to4[b]], 24);
246 s->coeff_ctx_last[vp56_b6to4[b]] = coeff_idx;
247 if (coeff_idx < ctx_last)
248 for (i=coeff_idx; i<=ctx_last; i++)
249 s->coeff_ctx[vp56_b6to4[b]][i] = 5;
250 s->above_blocks[s->above_block_idx[b]].not_null_dc = s->coeff_ctx[vp56_b6to4[b]][0];
251 }
252 }
253
254 static void vp5_default_models_init(vp56_context_t *s)
255 {
256 vp56_model_t *model = s->modelp;
257 int i;
258
259 for (i=0; i<2; i++) {
260 model->vector_sig[i] = 0x80;
261 model->vector_dct[i] = 0x80;
262 model->vector_pdi[i][0] = 0x55;
263 model->vector_pdi[i][1] = 0x80;
264 }
265 memcpy(model->mb_types_stats, vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
266 memset(model->vector_pdv, 0x80, sizeof(model->vector_pdv));
267 }
268
269 static int vp5_decode_init(AVCodecContext *avctx)
270 {
271 vp56_context_t *s = avctx->priv_data;
272
273 vp56_init(avctx, 1, 0);
274 s->vp56_coord_div = vp5_coord_div;
275 s->parse_vector_adjustment = vp5_parse_vector_adjustment;
276 s->adjust = vp5_adjust;
277 s->parse_coeff = vp5_parse_coeff;
278 s->default_models_init = vp5_default_models_init;
279 s->parse_vector_models = vp5_parse_vector_models;
280 s->parse_coeff_models = vp5_parse_coeff_models;
281 s->parse_header = vp5_parse_header;
282
283 return 0;
284 }
285
286 AVCodec vp5_decoder = {
287 "vp5",
288 CODEC_TYPE_VIDEO,
289 CODEC_ID_VP5,
290 sizeof(vp56_context_t),
291 vp5_decode_init,
292 NULL,
293 vp56_free,
294 vp56_decode_frame,
295 CODEC_CAP_DR1,
296 };