• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 "internal.h"
31 
32 #include "vp56.h"
33 #include "vp56data.h"
34 #include "vp5data.h"
35 
36 
vp5_parse_header(VP56Context * s,const uint8_t * buf,int buf_size)37 static int vp5_parse_header(VP56Context *s, const uint8_t *buf, int buf_size)
38 {
39     VP56RangeCoder *c = &s->c;
40     int rows, cols;
41     int ret;
42 
43     ret = ff_vp56_init_range_decoder(&s->c, buf, buf_size);
44     if (ret < 0)
45         return ret;
46     s->frames[VP56_FRAME_CURRENT]->key_frame = !vp56_rac_get(c);
47     vp56_rac_get(c);
48     ff_vp56_init_dequant(s, vp56_rac_gets(c, 6));
49     if (s->frames[VP56_FRAME_CURRENT]->key_frame)
50     {
51         int render_x, render_y;
52 
53         vp56_rac_gets(c, 8);
54         if(vp56_rac_gets(c, 5) > 5)
55             return AVERROR_INVALIDDATA;
56         vp56_rac_gets(c, 2);
57         if (vp56_rac_get(c)) {
58             avpriv_report_missing_feature(s->avctx, "Interlacing");
59             return AVERROR_PATCHWELCOME;
60         }
61         rows = vp56_rac_gets(c, 8);  /* number of stored macroblock rows */
62         cols = vp56_rac_gets(c, 8);  /* number of stored macroblock cols */
63         if (!rows || !cols) {
64             av_log(s->avctx, AV_LOG_ERROR, "Invalid size %dx%d\n",
65                    cols << 4, rows << 4);
66             return AVERROR_INVALIDDATA;
67         }
68         render_y = vp56_rac_gets(c, 8);  /* number of displayed macroblock rows */
69         render_x = vp56_rac_gets(c, 8);  /* number of displayed macroblock cols */
70         if (render_x == 0 || render_x > cols ||
71             render_y == 0 || render_y > rows)
72             return AVERROR_INVALIDDATA;
73         vp56_rac_gets(c, 2);
74         if (!s->macroblocks || /* first frame */
75             16*cols != s->avctx->coded_width ||
76             16*rows != s->avctx->coded_height) {
77             int ret = ff_set_dimensions(s->avctx, 16 * cols, 16 * rows);
78             if (ret < 0)
79                 return ret;
80             return VP56_SIZE_CHANGE;
81         }
82     } else if (!s->macroblocks)
83         return AVERROR_INVALIDDATA;
84     return 0;
85 }
86 
vp5_parse_vector_adjustment(VP56Context * s,VP56mv * vect)87 static void vp5_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
88 {
89     VP56RangeCoder *c = &s->c;
90     VP56Model *model = s->modelp;
91     int comp, di;
92 
93     for (comp=0; comp<2; comp++) {
94         int delta = 0;
95         if (vp56_rac_get_prob_branchy(c, model->vector_dct[comp])) {
96             int sign = vp56_rac_get_prob(c, model->vector_sig[comp]);
97             di  = vp56_rac_get_prob(c, model->vector_pdi[comp][0]);
98             di |= vp56_rac_get_prob(c, model->vector_pdi[comp][1]) << 1;
99             delta = vp56_rac_get_tree(c, ff_vp56_pva_tree,
100                                       model->vector_pdv[comp]);
101             delta = di | (delta << 2);
102             delta = (delta ^ -sign) + sign;
103         }
104         if (!comp)
105             vect->x = delta;
106         else
107             vect->y = delta;
108     }
109 }
110 
vp5_parse_vector_models(VP56Context * s)111 static void vp5_parse_vector_models(VP56Context *s)
112 {
113     VP56RangeCoder *c = &s->c;
114     VP56Model *model = s->modelp;
115     int comp, node;
116 
117     for (comp=0; comp<2; comp++) {
118         if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][0]))
119             model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
120         if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][1]))
121             model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
122         if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][2]))
123             model->vector_pdi[comp][0] = vp56_rac_gets_nn(c, 7);
124         if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][3]))
125             model->vector_pdi[comp][1] = vp56_rac_gets_nn(c, 7);
126     }
127 
128     for (comp=0; comp<2; comp++)
129         for (node=0; node<7; node++)
130             if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][4 + node]))
131                 model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
132 }
133 
vp5_parse_coeff_models(VP56Context * s)134 static int vp5_parse_coeff_models(VP56Context *s)
135 {
136     VP56RangeCoder *c = &s->c;
137     VP56Model *model = s->modelp;
138     uint8_t def_prob[11];
139     int node, cg, ctx;
140     int ct;    /* code type */
141     int pt;    /* plane type (0 for Y, 1 for U or V) */
142 
143     memset(def_prob, 0x80, sizeof(def_prob));
144 
145     for (pt=0; pt<2; pt++)
146         for (node=0; node<11; node++)
147             if (vp56_rac_get_prob_branchy(c, vp5_dccv_pct[pt][node])) {
148                 def_prob[node] = vp56_rac_gets_nn(c, 7);
149                 model->coeff_dccv[pt][node] = def_prob[node];
150             } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
151                 model->coeff_dccv[pt][node] = def_prob[node];
152             }
153 
154     for (ct=0; ct<3; ct++)
155         for (pt=0; pt<2; pt++)
156             for (cg=0; cg<6; cg++)
157                 for (node=0; node<11; node++)
158                     if (vp56_rac_get_prob_branchy(c, vp5_ract_pct[ct][pt][cg][node])) {
159                         def_prob[node] = vp56_rac_gets_nn(c, 7);
160                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
161                     } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
162                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
163                     }
164 
165     /* coeff_dcct is a linear combination of coeff_dccv */
166     for (pt=0; pt<2; pt++)
167         for (ctx=0; ctx<36; ctx++)
168             for (node=0; node<5; node++)
169                 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);
170 
171     /* coeff_acct is a linear combination of coeff_ract */
172     for (ct=0; ct<3; ct++)
173         for (pt=0; pt<2; pt++)
174             for (cg=0; cg<3; cg++)
175                 for (ctx=0; ctx<6; ctx++)
176                     for (node=0; node<5; node++)
177                         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);
178     return 0;
179 }
180 
vp5_parse_coeff(VP56Context * s)181 static int vp5_parse_coeff(VP56Context *s)
182 {
183     VP56RangeCoder *c = &s->c;
184     VP56Model *model = s->modelp;
185     uint8_t *permute = s->idct_scantable;
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     if (vpX_rac_is_end(c)) {
192         av_log(s->avctx, AV_LOG_ERROR, "End of AC stream reached in vp5_parse_coeff\n");
193         return AVERROR_INVALIDDATA;
194     }
195 
196     for (b=0; b<6; b++) {
197         int ct = 1;    /* code type */
198 
199         if (b > 3) pt = 1;
200 
201         ctx = 6*s->coeff_ctx[ff_vp56_b6to4[b]][0]
202               + s->above_blocks[s->above_block_idx[b]].not_null_dc;
203         model1 = model->coeff_dccv[pt];
204         model2 = model->coeff_dcct[pt][ctx];
205 
206         coeff_idx = 0;
207         for (;;) {
208             if (vp56_rac_get_prob_branchy(c, model2[0])) {
209                 if (vp56_rac_get_prob_branchy(c, model2[2])) {
210                     if (vp56_rac_get_prob_branchy(c, model2[3])) {
211                         s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 4;
212                         idx = vp56_rac_get_tree(c, ff_vp56_pc_tree, model1);
213                         sign = vp56_rac_get(c);
214                         coeff = ff_vp56_coeff_bias[idx+5];
215                         for (i=ff_vp56_coeff_bit_length[idx]; i>=0; i--)
216                             coeff += vp56_rac_get_prob(c, ff_vp56_coeff_parse_table[idx][i]) << i;
217                     } else {
218                         if (vp56_rac_get_prob_branchy(c, model2[4])) {
219                             coeff = 3 + vp56_rac_get_prob(c, model1[5]);
220                             s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 3;
221                         } else {
222                             coeff = 2;
223                             s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 2;
224                         }
225                         sign = vp56_rac_get(c);
226                     }
227                     ct = 2;
228                 } else {
229                     ct = 1;
230                     s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 1;
231                     sign = vp56_rac_get(c);
232                     coeff = 1;
233                 }
234                 coeff = (coeff ^ -sign) + sign;
235                 if (coeff_idx)
236                     coeff *= s->dequant_ac;
237                 s->block_coeff[b][permute[coeff_idx]] = coeff;
238             } else {
239                 if (ct && !vp56_rac_get_prob_branchy(c, model2[1]))
240                     break;
241                 ct = 0;
242                 s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 0;
243             }
244             coeff_idx++;
245             if (coeff_idx >= 64)
246                 break;
247 
248             cg = vp5_coeff_groups[coeff_idx];
249             ctx = s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx];
250             model1 = model->coeff_ract[pt][ct][cg];
251             model2 = cg > 2 ? model1 : model->coeff_acct[pt][ct][cg][ctx];
252         }
253 
254         ctx_last = FFMIN(s->coeff_ctx_last[ff_vp56_b6to4[b]], 24);
255         s->coeff_ctx_last[ff_vp56_b6to4[b]] = coeff_idx;
256         if (coeff_idx < ctx_last)
257             for (i=coeff_idx; i<=ctx_last; i++)
258                 s->coeff_ctx[ff_vp56_b6to4[b]][i] = 5;
259         s->above_blocks[s->above_block_idx[b]].not_null_dc = s->coeff_ctx[ff_vp56_b6to4[b]][0];
260         s->idct_selector[b] = 63;
261     }
262     return 0;
263 }
264 
vp5_default_models_init(VP56Context * s)265 static void vp5_default_models_init(VP56Context *s)
266 {
267     VP56Model *model = s->modelp;
268     int i;
269 
270     for (i=0; i<2; i++) {
271         model->vector_sig[i] = 0x80;
272         model->vector_dct[i] = 0x80;
273         model->vector_pdi[i][0] = 0x55;
274         model->vector_pdi[i][1] = 0x80;
275     }
276     memcpy(model->mb_types_stats, ff_vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
277     memset(model->vector_pdv, 0x80, sizeof(model->vector_pdv));
278 }
279 
vp5_decode_init(AVCodecContext * avctx)280 static av_cold int vp5_decode_init(AVCodecContext *avctx)
281 {
282     VP56Context *s = avctx->priv_data;
283     int ret;
284 
285     if ((ret = ff_vp56_init(avctx, 1, 0)) < 0)
286         return ret;
287     ff_vp5dsp_init(&s->vp56dsp);
288     s->vp56_coord_div = vp5_coord_div;
289     s->parse_vector_adjustment = vp5_parse_vector_adjustment;
290     s->parse_coeff = vp5_parse_coeff;
291     s->default_models_init = vp5_default_models_init;
292     s->parse_vector_models = vp5_parse_vector_models;
293     s->parse_coeff_models = vp5_parse_coeff_models;
294     s->parse_header = vp5_parse_header;
295 
296     return 0;
297 }
298 
299 AVCodec ff_vp5_decoder = {
300     .name           = "vp5",
301     .long_name      = NULL_IF_CONFIG_SMALL("On2 VP5"),
302     .type           = AVMEDIA_TYPE_VIDEO,
303     .id             = AV_CODEC_ID_VP5,
304     .priv_data_size = sizeof(VP56Context),
305     .init           = vp5_decode_init,
306     .close          = ff_vp56_free,
307     .decode         = ff_vp56_decode_frame,
308     .capabilities   = AV_CODEC_CAP_DR1,
309 };
310