aboutsummaryrefslogtreecommitdiffstats
path: root/libavcodec/vp5.c
blob: 54db620bde69ff298d955bc7739e023064bdff2c (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
/*
 * Copyright (C) 2006  Aurelien Jacobs <aurel@gnuage.org>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * VP5 compatible video decoder
 */

#include <stdlib.h>
#include <string.h>

#include "avcodec.h"
#include "internal.h"

#include "vp56.h"
#include "vp56data.h"
#include "vp5data.h"


static int vp5_parse_header(VP56Context *s, const uint8_t *buf, int buf_size)
{
    VP56RangeCoder *c = &s->c;
    int rows, cols;

    ff_vp56_init_range_decoder(&s->c, buf, buf_size);
    s->frames[VP56_FRAME_CURRENT]->key_frame = !vp56_rac_get(c);
    vp56_rac_get(c);
    ff_vp56_init_dequant(s, vp56_rac_gets(c, 6));
    if (s->frames[VP56_FRAME_CURRENT]->key_frame)
    {
        vp56_rac_gets(c, 8);
        if(vp56_rac_gets(c, 5) > 5)
            return AVERROR_INVALIDDATA;
        vp56_rac_gets(c, 2);
        if (vp56_rac_get(c)) {
            av_log(s->avctx, AV_LOG_ERROR, "interlacing not supported\n");
            return AVERROR_PATCHWELCOME;
        }
        rows = vp56_rac_gets(c, 8);  /* number of stored macroblock rows */
        cols = vp56_rac_gets(c, 8);  /* number of stored macroblock cols */
        if (!rows || !cols) {
            av_log(s->avctx, AV_LOG_ERROR, "Invalid size %dx%d\n",
                   cols << 4, rows << 4);
            return AVERROR_INVALIDDATA;
        }
        vp56_rac_gets(c, 8);  /* number of displayed macroblock rows */
        vp56_rac_gets(c, 8);  /* number of displayed macroblock cols */
        vp56_rac_gets(c, 2);
        if (!s->macroblocks || /* first frame */
            16*cols != s->avctx->coded_width ||
            16*rows != s->avctx->coded_height) {
            int ret = ff_set_dimensions(s->avctx, 16 * cols, 16 * rows);
            if (ret < 0)
                return ret;
            return VP56_SIZE_CHANGE;
        }
    } else if (!s->macroblocks)
        return AVERROR_INVALIDDATA;
    return 0;
}

static void vp5_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
{
    VP56RangeCoder *c = &s->c;
    VP56Model *model = s->modelp;
    int comp, di;

    for (comp=0; comp<2; comp++) {
        int delta = 0;
        if (vp56_rac_get_prob_branchy(c, model->vector_dct[comp])) {
            int sign = vp56_rac_get_prob(c, model->vector_sig[comp]);
            di  = vp56_rac_get_prob(c, model->vector_pdi[comp][0]);
            di |= vp56_rac_get_prob(c, model->vector_pdi[comp][1]) << 1;
            delta = vp56_rac_get_tree(c, ff_vp56_pva_tree,
                                      model->vector_pdv[comp]);
            delta = di | (delta << 2);
            delta = (delta ^ -sign) + sign;
        }
        if (!comp)
            vect->x = delta;
        else
            vect->y = delta;
    }
}

static void vp5_parse_vector_models(VP56Context *s)
{
    VP56RangeCoder *c = &s->c;
    VP56Model *model = s->modelp;
    int comp, node;

    for (comp=0; comp<2; comp++) {
        if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][0]))
            model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
        if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][1]))
            model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
        if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][2]))
            model->vector_pdi[comp][0] = vp56_rac_gets_nn(c, 7);
        if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][3]))
            model->vector_pdi[comp][1] = vp56_rac_gets_nn(c, 7);
    }

    for (comp=0; comp<2; comp++)
        for (node=0; node<7; node++)
            if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][4 + node]))
                model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
}

static int vp5_parse_coeff_models(VP56Context *s)
{
    VP56RangeCoder *c = &s->c;
    VP56Model *model = s->modelp;
    uint8_t def_prob[11];
    int node, cg, ctx;
    int ct;    /* code type */
    int pt;    /* plane type (0 for Y, 1 for U or V) */

    memset(def_prob, 0x80, sizeof(def_prob));

    for (pt=0; pt<2; pt++)
        for (node=0; node<11; node++)
            if (vp56_rac_get_prob_branchy(c, vp5_dccv_pct[pt][node])) {
                def_prob[node] = vp56_rac_gets_nn(c, 7);
                model->coeff_dccv[pt][node] = def_prob[node];
            } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
                model->coeff_dccv[pt][node] = def_prob[node];
            }

    for (ct=0; ct<3; ct++)
        for (pt=0; pt<2; pt++)
            for (cg=0; cg<6; cg++)
                for (node=0; node<11; node++)
                    if (vp56_rac_get_prob_branchy(c, vp5_ract_pct[ct][pt][cg][node])) {
                        def_prob[node] = vp56_rac_gets_nn(c, 7);
                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
                    } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
                    }

    /* coeff_dcct is a linear combination of coeff_dccv */
    for (pt=0; pt<2; pt++)
        for (ctx=0; ctx<36; ctx++)
            for (node=0; node<5; node++)
                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);

    /* coeff_acct is a linear combination of coeff_ract */
    for (ct=0; ct<3; ct++)
        for (pt=0; pt<2; pt++)
            for (cg=0; cg<3; cg++)
                for (ctx=0; ctx<6; ctx++)
                    for (node=0; node<5; node++)
                        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);
    return 0;
}

static int vp5_parse_coeff(VP56Context *s)
{
    VP56RangeCoder *c = &s->c;
    VP56Model *model = s->modelp;
    uint8_t *permute = s->idct_scantable;
    uint8_t *model1, *model2;
    int coeff, sign, coeff_idx;
    int b, i, cg, idx, ctx, ctx_last;
    int pt = 0;    /* plane type (0 for Y, 1 for U or V) */

    if (c->end <= c->buffer && c->bits >= 0) {
        av_log(s->avctx, AV_LOG_ERROR, "End of AC stream reached in vp5_parse_coeff\n");
        return AVERROR_INVALIDDATA;
    }

    for (b=0; b<6; b++) {
        int ct = 1;    /* code type */

        if (b > 3) pt = 1;

        ctx = 6*s->coeff_ctx[ff_vp56_b6to4[b]][0]
              + s->above_blocks[s->above_block_idx[b]].not_null_dc;
        model1 = model->coeff_dccv[pt];
        model2 = model->coeff_dcct[pt][ctx];

        coeff_idx = 0;
        for (;;) {
            if (vp56_rac_get_prob_branchy(c, model2[0])) {
                if (vp56_rac_get_prob_branchy(c, model2[2])) {
                    if (vp56_rac_get_prob_branchy(c, model2[3])) {
                        s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 4;
                        idx = vp56_rac_get_tree(c, ff_vp56_pc_tree, model1);
                        sign = vp56_rac_get(c);
                        coeff = ff_vp56_coeff_bias[idx+5];
                        for (i=ff_vp56_coeff_bit_length[idx]; i>=0; i--)
                            coeff += vp56_rac_get_prob(c, ff_vp56_coeff_parse_table[idx][i]) << i;
                    } else {
                        if (vp56_rac_get_prob_branchy(c, model2[4])) {
                            coeff = 3 + vp56_rac_get_prob(c, model1[5]);
                            s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 3;
                        } else {
                            coeff = 2;
                            s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 2;
                        }
                        sign = vp56_rac_get(c);
                    }
                    ct = 2;
                } else {
                    ct = 1;
                    s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 1;
                    sign = vp56_rac_get(c);
                    coeff = 1;
                }
                coeff = (coeff ^ -sign) + sign;
                if (coeff_idx)
                    coeff *= s->dequant_ac;
                s->block_coeff[b][permute[coeff_idx]] = coeff;
            } else {
                if (ct && !vp56_rac_get_prob_branchy(c, model2[1]))
                    break;
                ct = 0;
                s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 0;
            }
            coeff_idx++;
            if (coeff_idx >= 64)
                break;

            cg = vp5_coeff_groups[coeff_idx];
            ctx = s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx];
            model1 = model->coeff_ract[pt][ct][cg];
            model2 = cg > 2 ? model1 : model->coeff_acct[pt][ct][cg][ctx];
        }

        ctx_last = FFMIN(s->coeff_ctx_last[ff_vp56_b6to4[b]], 24);
        s->coeff_ctx_last[ff_vp56_b6to4[b]] = coeff_idx;
        if (coeff_idx < ctx_last)
            for (i=coeff_idx; i<=ctx_last; i++)
                s->coeff_ctx[ff_vp56_b6to4[b]][i] = 5;
        s->above_blocks[s->above_block_idx[b]].not_null_dc = s->coeff_ctx[ff_vp56_b6to4[b]][0];
    }
    return 0;
}

static void vp5_default_models_init(VP56Context *s)
{
    VP56Model *model = s->modelp;
    int i;

    for (i=0; i<2; i++) {
        model->vector_sig[i] = 0x80;
        model->vector_dct[i] = 0x80;
        model->vector_pdi[i][0] = 0x55;
        model->vector_pdi[i][1] = 0x80;
    }
    memcpy(model->mb_types_stats, ff_vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
    memset(model->vector_pdv, 0x80, sizeof(model->vector_pdv));
}

static av_cold int vp5_decode_init(AVCodecContext *avctx)
{
    VP56Context *s = avctx->priv_data;
    int ret;

    if ((ret = ff_vp56_init(avctx, 1, 0)) < 0)
        return ret;
    s->vp56_coord_div = vp5_coord_div;
    s->parse_vector_adjustment = vp5_parse_vector_adjustment;
    s->parse_coeff = vp5_parse_coeff;
    s->default_models_init = vp5_default_models_init;
    s->parse_vector_models = vp5_parse_vector_models;
    s->parse_coeff_models = vp5_parse_coeff_models;
    s->parse_header = vp5_parse_header;

    return 0;
}

AVCodec ff_vp5_decoder = {
    .name           = "vp5",
    .long_name      = NULL_IF_CONFIG_SMALL("On2 VP5"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_VP5,
    .priv_data_size = sizeof(VP56Context),
    .init           = vp5_decode_init,
    .close          = ff_vp56_free,
    .decode         = ff_vp56_decode_frame,
    .capabilities   = AV_CODEC_CAP_DR1,
};