3 * VP5 compatible video decoder
5 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
7 * This file is part of FFmpeg.
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.
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.
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
29 #include "bitstream.h"
30 #include "mpegvideo.h"
37 static int vp5_parse_header(vp56_context_t *s, const uint8_t *buf, int buf_size,
40 vp56_range_coder_t *c = &s->c;
43 vp56_init_range_decoder(&s->c, buf, buf_size);
44 s->framep[VP56_FRAME_CURRENT]->key_frame = !vp56_rac_get(c);
46 vp56_init_dequant(s, vp56_rac_gets(c, 6));
47 if (s->framep[VP56_FRAME_CURRENT]->key_frame)
50 if(vp56_rac_gets(c, 5) > 5)
53 if (vp56_rac_get(c)) {
54 av_log(s->avctx, AV_LOG_ERROR, "interlacing not supported\n");
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 */
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);
71 /* Gives very similar result than the vp6 version except in a few cases */
72 static int vp5_adjust(int v, int t)
88 static void vp5_parse_vector_adjustment(vp56_context_t *s, vp56_mv_t *vect)
90 vp56_range_coder_t *c = &s->c;
91 vp56_model_t *model = s->modelp;
94 for (comp=0; comp<2; comp++) {
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;
112 static void vp5_parse_vector_models(vp56_context_t *s)
114 vp56_range_coder_t *c = &s->c;
115 vp56_model_t *model = s->modelp;
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);
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);
135 static void vp5_parse_coeff_models(vp56_context_t *s)
137 vp56_range_coder_t *c = &s->c;
138 vp56_model_t *model = s->modelp;
139 uint8_t def_prob[11];
141 int ct; /* code type */
142 int pt; /* plane type (0 for Y, 1 for U or V) */
144 memset(def_prob, 0x80, sizeof(def_prob));
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];
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];
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);
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);
181 static void vp5_parse_coeff(vp56_context_t *s)
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) */
191 for (b=0; b<6; b++) {
192 int ct = 1; /* code type */
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];
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;
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;
217 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 2;
219 sign = vp56_rac_get(c);
224 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 1;
225 sign = vp56_rac_get(c);
228 coeff = (coeff ^ -sign) + sign;
230 coeff *= s->dequant_ac;
231 s->block_coeff[b][permute[coeff_idx]] = coeff;
233 if (ct && !vp56_rac_get_prob(c, model2[1]))
236 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 0;
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];
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];
254 static void vp5_default_models_init(vp56_context_t *s)
256 vp56_model_t *model = s->modelp;
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;
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));
269 static int vp5_decode_init(AVCodecContext *avctx)
271 vp56_context_t *s = avctx->priv_data;
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;
286 AVCodec vp5_decoder = {
290 sizeof(vp56_context_t),