ffmpeg/libavcodec/vp5.c

   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 "get_bits.h"
  31 #include "internal.h"
  32
  33 #include "vp56.h"
  34 #include "vp56data.h"
  35 #include "vp5data.h"
  36
  37
  38 static int vp5_parse_header(VP56Context *s, const uint8_t *buf, int buf_size)
  39 {
  40     VP56RangeCoder *c = &s->c;
  41     int rows, cols;
  42
  43     ff_vp56_init_range_decoder(&s->c, buf, buf_size);
  44     s->frames[VP56_FRAME_CURRENT]->key_frame = !vp56_rac_get(c);
  45     vp56_rac_get(c);
  46     ff_vp56_init_dequant(s, vp56_rac_gets(c, 6));
  47     if (s->frames[VP56_FRAME_CURRENT]->key_frame)
  48     {
  49         vp56_rac_gets(c, 8);
  50         if(vp56_rac_gets(c, 5) > 5)
  51             return AVERROR_INVALIDDATA;
  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 AVERROR_PATCHWELCOME;
  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         if (!rows || !cols) {
  60             av_log(s->avctx, AV_LOG_ERROR, "Invalid size %dx%d\n",
  61                    cols << 4, rows << 4);
  62             return AVERROR_INVALIDDATA;
  63         }
  64         vp56_rac_gets(c, 8);  /* number of displayed macroblock rows */
  65         vp56_rac_gets(c, 8);  /* number of displayed macroblock cols */
  66         vp56_rac_gets(c, 2);
  67         if (!s->macroblocks || /* first frame */
  68             16*cols != s->avctx->coded_width ||
  69             16*rows != s->avctx->coded_height) {
  70             int ret = ff_set_dimensions(s->avctx, 16 * cols, 16 * rows);
  71             if (ret < 0)
  72                 return ret;
  73             return VP56_SIZE_CHANGE;
  74         }
  75     } else if (!s->macroblocks)
  76         return AVERROR_INVALIDDATA;
  77     return 0;
  78 }
  79
  80 static void vp5_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
  81 {
  82     VP56RangeCoder *c = &s->c;
  83     VP56Model *model = s->modelp;
  84     int comp, di;
  85
  86     for (comp=0; comp<2; comp++) {
  87         int delta = 0;
  88         if (vp56_rac_get_prob_branchy(c, model->vector_dct[comp])) {
  89             int sign = vp56_rac_get_prob(c, model->vector_sig[comp]);
  90             di  = vp56_rac_get_prob(c, model->vector_pdi[comp][0]);
  91             di |= vp56_rac_get_prob(c, model->vector_pdi[comp][1]) << 1;
  92             delta = vp56_rac_get_tree(c, ff_vp56_pva_tree,
  93                                       model->vector_pdv[comp]);
  94             delta = di | (delta << 2);
  95             delta = (delta ^ -sign) + sign;
  96         }
  97         if (!comp)
  98             vect->x = delta;
  99         else
 100             vect->y = delta;
 101     }
 102 }
 103
 104 static void vp5_parse_vector_models(VP56Context *s)
 105 {
 106     VP56RangeCoder *c = &s->c;
 107     VP56Model *model = s->modelp;
 108     int comp, node;
 109
 110     for (comp=0; comp<2; comp++) {
 111         if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][0]))
 112             model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
 113         if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][1]))
 114             model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
 115         if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][2]))
 116             model->vector_pdi[comp][0] = vp56_rac_gets_nn(c, 7);
 117         if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][3]))
 118             model->vector_pdi[comp][1] = vp56_rac_gets_nn(c, 7);
 119     }
 120
 121     for (comp=0; comp<2; comp++)
 122         for (node=0; node<7; node++)
 123             if (vp56_rac_get_prob_branchy(c, vp5_vmc_pct[comp][4 + node]))
 124                 model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
 125 }
 126
 127 static int vp5_parse_coeff_models(VP56Context *s)
 128 {
 129     VP56RangeCoder *c = &s->c;
 130     VP56Model *model = s->modelp;
 131     uint8_t def_prob[11];
 132     int node, cg, ctx;
 133     int ct;    /* code type */
 134     int pt;    /* plane type (0 for Y, 1 for U or V) */
 135
 136     memset(def_prob, 0x80, sizeof(def_prob));
 137
 138     for (pt=0; pt<2; pt++)
 139         for (node=0; node<11; node++)
 140             if (vp56_rac_get_prob_branchy(c, vp5_dccv_pct[pt][node])) {
 141                 def_prob[node] = vp56_rac_gets_nn(c, 7);
 142                 model->coeff_dccv[pt][node] = def_prob[node];
 143             } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
 144                 model->coeff_dccv[pt][node] = def_prob[node];
 145             }
 146
 147     for (ct=0; ct<3; ct++)
 148         for (pt=0; pt<2; pt++)
 149             for (cg=0; cg<6; cg++)
 150                 for (node=0; node<11; node++)
 151                     if (vp56_rac_get_prob_branchy(c, vp5_ract_pct[ct][pt][cg][node])) {
 152                         def_prob[node] = vp56_rac_gets_nn(c, 7);
 153                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
 154                     } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
 155                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
 156                     }
 157
 158     /* coeff_dcct is a linear combination of coeff_dccv */
 159     for (pt=0; pt<2; pt++)
 160         for (ctx=0; ctx<36; ctx++)
 161             for (node=0; node<5; node++)
 162                 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);
 163
 164     /* coeff_acct is a linear combination of coeff_ract */
 165     for (ct=0; ct<3; ct++)
 166         for (pt=0; pt<2; pt++)
 167             for (cg=0; cg<3; cg++)
 168                 for (ctx=0; ctx<6; ctx++)
 169                     for (node=0; node<5; node++)
 170                         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);
 171     return 0;
 172 }
 173
 174 static void vp5_parse_coeff(VP56Context *s)
 175 {
 176     VP56RangeCoder *c = &s->c;
 177     VP56Model *model = s->modelp;
 178     uint8_t *permute = s->idct_scantable;
 179     uint8_t *model1, *model2;
 180     int coeff, sign, coeff_idx;
 181     int b, i, cg, idx, ctx, ctx_last;
 182     int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
 183
 184     for (b=0; b<6; b++) {
 185         int ct = 1;    /* code type */
 186
 187         if (b > 3) pt = 1;
 188
 189         ctx = 6*s->coeff_ctx[ff_vp56_b6to4[b]][0]
 190               + s->above_blocks[s->above_block_idx[b]].not_null_dc;
 191         model1 = model->coeff_dccv[pt];
 192         model2 = model->coeff_dcct[pt][ctx];
 193
 194         coeff_idx = 0;
 195         for (;;) {
 196             if (vp56_rac_get_prob_branchy(c, model2[0])) {
 197                 if (vp56_rac_get_prob_branchy(c, model2[2])) {
 198                     if (vp56_rac_get_prob_branchy(c, model2[3])) {
 199                         s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 4;
 200                         idx = vp56_rac_get_tree(c, ff_vp56_pc_tree, model1);
 201                         sign = vp56_rac_get(c);
 202                         coeff = ff_vp56_coeff_bias[idx+5];
 203                         for (i=ff_vp56_coeff_bit_length[idx]; i>=0; i--)
 204                             coeff += vp56_rac_get_prob(c, ff_vp56_coeff_parse_table[idx][i]) << i;
 205                     } else {
 206                         if (vp56_rac_get_prob_branchy(c, model2[4])) {
 207                             coeff = 3 + vp56_rac_get_prob(c, model1[5]);
 208                             s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 3;
 209                         } else {
 210                             coeff = 2;
 211                             s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 2;
 212                         }
 213                         sign = vp56_rac_get(c);
 214                     }
 215                     ct = 2;
 216                 } else {
 217                     ct = 1;
 218                     s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 1;
 219                     sign = vp56_rac_get(c);
 220                     coeff = 1;
 221                 }
 222                 coeff = (coeff ^ -sign) + sign;
 223                 if (coeff_idx)
 224                     coeff *= s->dequant_ac;
 225                 s->block_coeff[b][permute[coeff_idx]] = coeff;
 226             } else {
 227                 if (ct && !vp56_rac_get_prob_branchy(c, model2[1]))
 228                     break;
 229                 ct = 0;
 230                 s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx] = 0;
 231             }
 232             coeff_idx++;
 233             if (coeff_idx >= 64)
 234                 break;
 235
 236             cg = vp5_coeff_groups[coeff_idx];
 237             ctx = s->coeff_ctx[ff_vp56_b6to4[b]][coeff_idx];
 238             model1 = model->coeff_ract[pt][ct][cg];
 239             model2 = cg > 2 ? model1 : model->coeff_acct[pt][ct][cg][ctx];
 240         }
 241
 242         ctx_last = FFMIN(s->coeff_ctx_last[ff_vp56_b6to4[b]], 24);
 243         s->coeff_ctx_last[ff_vp56_b6to4[b]] = coeff_idx;
 244         if (coeff_idx < ctx_last)
 245             for (i=coeff_idx; i<=ctx_last; i++)
 246                 s->coeff_ctx[ff_vp56_b6to4[b]][i] = 5;
 247         s->above_blocks[s->above_block_idx[b]].not_null_dc = s->coeff_ctx[ff_vp56_b6to4[b]][0];
 248     }
 249 }
 250
 251 static void vp5_default_models_init(VP56Context *s)
 252 {
 253     VP56Model *model = s->modelp;
 254     int i;
 255
 256     for (i=0; i<2; i++) {
 257         model->vector_sig[i] = 0x80;
 258         model->vector_dct[i] = 0x80;
 259         model->vector_pdi[i][0] = 0x55;
 260         model->vector_pdi[i][1] = 0x80;
 261     }
 262     memcpy(model->mb_types_stats, ff_vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
 263     memset(model->vector_pdv, 0x80, sizeof(model->vector_pdv));
 264 }
 265
 266 static av_cold int vp5_decode_init(AVCodecContext *avctx)
 267 {
 268     VP56Context *s = avctx->priv_data;
 269     int ret;
 270
 271     if ((ret = ff_vp56_init(avctx, 1, 0)) < 0)
 272         return ret;
 273     s->vp56_coord_div = vp5_coord_div;
 274     s->parse_vector_adjustment = vp5_parse_vector_adjustment;
 275     s->parse_coeff = vp5_parse_coeff;
 276     s->default_models_init = vp5_default_models_init;
 277     s->parse_vector_models = vp5_parse_vector_models;
 278     s->parse_coeff_models = vp5_parse_coeff_models;
 279     s->parse_header = vp5_parse_header;
 280
 281     return 0;
 282 }
 283
 284 AVCodec ff_vp5_decoder = {
 285     .name           = "vp5",
 286     .long_name      = NULL_IF_CONFIG_SMALL("On2 VP5"),
 287     .type           = AVMEDIA_TYPE_VIDEO,
 288     .id             = AV_CODEC_ID_VP5,
 289     .priv_data_size = sizeof(VP56Context),
 290     .init           = vp5_decode_init,
 291     .close          = ff_vp56_free,
 292     .decode         = ff_vp56_decode_frame,
 293     .capabilities   = CODEC_CAP_DR1,
 294 };