1/**
2 * @file
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 "get_bits.h"
30
31#include "vp56.h"
32#include "vp56data.h"
33#include "vp5data.h"
34
35
36static int vp5_parse_header(VP56Context *s, const uint8_t *buf, int buf_size,
37                            int *golden_frame)
38{
39    VP56RangeCoder *c = &s->c;
40    int rows, cols;
41
42    vp56_init_range_decoder(&s->c, buf, buf_size);
43    s->framep[VP56_FRAME_CURRENT]->key_frame = !vp56_rac_get(c);
44    vp56_rac_get(c);
45    vp56_init_dequant(s, vp56_rac_gets(c, 6));
46    if (s->framep[VP56_FRAME_CURRENT]->key_frame)
47    {
48        vp56_rac_gets(c, 8);
49        if(vp56_rac_gets(c, 5) > 5)
50            return 0;
51        vp56_rac_gets(c, 2);
52        if (vp56_rac_get(c)) {
53            av_log(s->avctx, AV_LOG_ERROR, "interlacing not supported\n");
54            return 0;
55        }
56        rows = vp56_rac_gets(c, 8);  /* number of stored macroblock rows */
57        cols = vp56_rac_gets(c, 8);  /* number of stored macroblock cols */
58        vp56_rac_gets(c, 8);  /* number of displayed macroblock rows */
59        vp56_rac_gets(c, 8);  /* number of displayed macroblock cols */
60        vp56_rac_gets(c, 2);
61        if (!s->macroblocks || /* first frame */
62            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    } else if (!s->macroblocks)
68        return 0;
69    return 1;
70}
71
72static void vp5_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
73{
74    VP56RangeCoder *c = &s->c;
75    VP56Model *model = s->modelp;
76    int comp, di;
77
78    for (comp=0; comp<2; comp++) {
79        int delta = 0;
80        if (vp56_rac_get_prob(c, model->vector_dct[comp])) {
81            int sign = vp56_rac_get_prob(c, model->vector_sig[comp]);
82            di  = vp56_rac_get_prob(c, model->vector_pdi[comp][0]);
83            di |= vp56_rac_get_prob(c, model->vector_pdi[comp][1]) << 1;
84            delta = vp56_rac_get_tree(c, vp56_pva_tree,
85                                      model->vector_pdv[comp]);
86            delta = di | (delta << 2);
87            delta = (delta ^ -sign) + sign;
88        }
89        if (!comp)
90            vect->x = delta;
91        else
92            vect->y = delta;
93    }
94}
95
96static void vp5_parse_vector_models(VP56Context *s)
97{
98    VP56RangeCoder *c = &s->c;
99    VP56Model *model = s->modelp;
100    int comp, node;
101
102    for (comp=0; comp<2; comp++) {
103        if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][0]))
104            model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
105        if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][1]))
106            model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
107        if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][2]))
108            model->vector_pdi[comp][0] = vp56_rac_gets_nn(c, 7);
109        if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][3]))
110            model->vector_pdi[comp][1] = vp56_rac_gets_nn(c, 7);
111    }
112
113    for (comp=0; comp<2; comp++)
114        for (node=0; node<7; node++)
115            if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][4 + node]))
116                model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
117}
118
119static void vp5_parse_coeff_models(VP56Context *s)
120{
121    VP56RangeCoder *c = &s->c;
122    VP56Model *model = s->modelp;
123    uint8_t def_prob[11];
124    int node, cg, ctx;
125    int ct;    /* code type */
126    int pt;    /* plane type (0 for Y, 1 for U or V) */
127
128    memset(def_prob, 0x80, sizeof(def_prob));
129
130    for (pt=0; pt<2; pt++)
131        for (node=0; node<11; node++)
132            if (vp56_rac_get_prob(c, vp5_dccv_pct[pt][node])) {
133                def_prob[node] = vp56_rac_gets_nn(c, 7);
134                model->coeff_dccv[pt][node] = def_prob[node];
135            } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
136                model->coeff_dccv[pt][node] = def_prob[node];
137            }
138
139    for (ct=0; ct<3; ct++)
140        for (pt=0; pt<2; pt++)
141            for (cg=0; cg<6; cg++)
142                for (node=0; node<11; node++)
143                    if (vp56_rac_get_prob(c, vp5_ract_pct[ct][pt][cg][node])) {
144                        def_prob[node] = vp56_rac_gets_nn(c, 7);
145                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
146                    } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
147                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
148                    }
149
150    /* coeff_dcct is a linear combination of coeff_dccv */
151    for (pt=0; pt<2; pt++)
152        for (ctx=0; ctx<36; ctx++)
153            for (node=0; node<5; node++)
154                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);
155
156    /* coeff_acct is a linear combination of coeff_ract */
157    for (ct=0; ct<3; ct++)
158        for (pt=0; pt<2; pt++)
159            for (cg=0; cg<3; cg++)
160                for (ctx=0; ctx<6; ctx++)
161                    for (node=0; node<5; node++)
162                        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);
163}
164
165static void vp5_parse_coeff(VP56Context *s)
166{
167    VP56RangeCoder *c = &s->c;
168    VP56Model *model = s->modelp;
169    uint8_t *permute = s->scantable.permutated;
170    uint8_t *model1, *model2;
171    int coeff, sign, coeff_idx;
172    int b, i, cg, idx, ctx, ctx_last;
173    int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
174
175    for (b=0; b<6; b++) {
176        int ct = 1;    /* code type */
177
178        if (b > 3) pt = 1;
179
180        ctx = 6*s->coeff_ctx[vp56_b6to4[b]][0]
181              + s->above_blocks[s->above_block_idx[b]].not_null_dc;
182        model1 = model->coeff_dccv[pt];
183        model2 = model->coeff_dcct[pt][ctx];
184
185        for (coeff_idx=0; coeff_idx<64; ) {
186            if (vp56_rac_get_prob(c, model2[0])) {
187                if (vp56_rac_get_prob(c, model2[2])) {
188                    if (vp56_rac_get_prob(c, model2[3])) {
189                        s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 4;
190                        idx = vp56_rac_get_tree(c, vp56_pc_tree, model1);
191                        sign = vp56_rac_get(c);
192                        coeff = vp56_coeff_bias[idx+5];
193                        for (i=vp56_coeff_bit_length[idx]; i>=0; i--)
194                            coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i;
195                    } else {
196                        if (vp56_rac_get_prob(c, model2[4])) {
197                            coeff = 3 + vp56_rac_get_prob(c, model1[5]);
198                            s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 3;
199                        } else {
200                            coeff = 2;
201                            s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 2;
202                        }
203                        sign = vp56_rac_get(c);
204                    }
205                    ct = 2;
206                } else {
207                    ct = 1;
208                    s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 1;
209                    sign = vp56_rac_get(c);
210                    coeff = 1;
211                }
212                coeff = (coeff ^ -sign) + sign;
213                if (coeff_idx)
214                    coeff *= s->dequant_ac;
215                s->block_coeff[b][permute[coeff_idx]] = coeff;
216            } else {
217                if (ct && !vp56_rac_get_prob(c, model2[1]))
218                    break;
219                ct = 0;
220                s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 0;
221            }
222
223            cg = vp5_coeff_groups[++coeff_idx];
224            ctx = s->coeff_ctx[vp56_b6to4[b]][coeff_idx];
225            model1 = model->coeff_ract[pt][ct][cg];
226            model2 = cg > 2 ? model1 : model->coeff_acct[pt][ct][cg][ctx];
227        }
228
229        ctx_last = FFMIN(s->coeff_ctx_last[vp56_b6to4[b]], 24);
230        s->coeff_ctx_last[vp56_b6to4[b]] = coeff_idx;
231        if (coeff_idx < ctx_last)
232            for (i=coeff_idx; i<=ctx_last; i++)
233                s->coeff_ctx[vp56_b6to4[b]][i] = 5;
234        s->above_blocks[s->above_block_idx[b]].not_null_dc = s->coeff_ctx[vp56_b6to4[b]][0];
235    }
236}
237
238static void vp5_default_models_init(VP56Context *s)
239{
240    VP56Model *model = s->modelp;
241    int i;
242
243    for (i=0; i<2; i++) {
244        model->vector_sig[i] = 0x80;
245        model->vector_dct[i] = 0x80;
246        model->vector_pdi[i][0] = 0x55;
247        model->vector_pdi[i][1] = 0x80;
248    }
249    memcpy(model->mb_types_stats, vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
250    memset(model->vector_pdv, 0x80, sizeof(model->vector_pdv));
251}
252
253static av_cold int vp5_decode_init(AVCodecContext *avctx)
254{
255    VP56Context *s = avctx->priv_data;
256
257    vp56_init(avctx, 1, 0);
258    s->vp56_coord_div = vp5_coord_div;
259    s->parse_vector_adjustment = vp5_parse_vector_adjustment;
260    s->parse_coeff = vp5_parse_coeff;
261    s->default_models_init = vp5_default_models_init;
262    s->parse_vector_models = vp5_parse_vector_models;
263    s->parse_coeff_models = vp5_parse_coeff_models;
264    s->parse_header = vp5_parse_header;
265
266    return 0;
267}
268
269AVCodec vp5_decoder = {
270    "vp5",
271    AVMEDIA_TYPE_VIDEO,
272    CODEC_ID_VP5,
273    sizeof(VP56Context),
274    vp5_decode_init,
275    NULL,
276    vp56_free,
277    vp56_decode_frame,
278    CODEC_CAP_DR1,
279    .long_name = NULL_IF_CONFIG_SMALL("On2 VP5"),
280};
281