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libavcodec/vp5.c

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00001 
00024 #include <stdlib.h>
00025 #include <string.h>
00026 
00027 #include "avcodec.h"
00028 #include "dsputil.h"
00029 #include "get_bits.h"
00030 
00031 #include "vp56.h"
00032 #include "vp56data.h"
00033 #include "vp5data.h"
00034 
00035 
00036 static int vp5_parse_header(VP56Context *s, const uint8_t *buf, int buf_size,
00037                             int *golden_frame)
00038 {
00039     VP56RangeCoder *c = &s->c;
00040     int rows, cols;
00041 
00042     ff_vp56_init_range_decoder(&s->c, buf, buf_size);
00043     s->framep[VP56_FRAME_CURRENT]->key_frame = !vp56_rac_get(c);
00044     vp56_rac_get(c);
00045     ff_vp56_init_dequant(s, vp56_rac_gets(c, 6));
00046     if (s->framep[VP56_FRAME_CURRENT]->key_frame)
00047     {
00048         vp56_rac_gets(c, 8);
00049         if(vp56_rac_gets(c, 5) > 5)
00050             return 0;
00051         vp56_rac_gets(c, 2);
00052         if (vp56_rac_get(c)) {
00053             av_log(s->avctx, AV_LOG_ERROR, "interlacing not supported\n");
00054             return 0;
00055         }
00056         rows = vp56_rac_gets(c, 8);  /* number of stored macroblock rows */
00057         cols = vp56_rac_gets(c, 8);  /* number of stored macroblock cols */
00058         if (!rows || !cols) {
00059             av_log(s->avctx, AV_LOG_ERROR, "Invalid size %dx%d\n",
00060                    cols << 4, rows << 4);
00061             return 0;
00062         }
00063         vp56_rac_gets(c, 8);  /* number of displayed macroblock rows */
00064         vp56_rac_gets(c, 8);  /* number of displayed macroblock cols */
00065         vp56_rac_gets(c, 2);
00066         if (!s->macroblocks || /* first frame */
00067             16*cols != s->avctx->coded_width ||
00068             16*rows != s->avctx->coded_height) {
00069             avcodec_set_dimensions(s->avctx, 16*cols, 16*rows);
00070             return 2;
00071         }
00072     } else if (!s->macroblocks)
00073         return 0;
00074     return 1;
00075 }
00076 
00077 static void vp5_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
00078 {
00079     VP56RangeCoder *c = &s->c;
00080     VP56Model *model = s->modelp;
00081     int comp, di;
00082 
00083     for (comp=0; comp<2; comp++) {
00084         int delta = 0;
00085         if (vp56_rac_get_prob(c, model->vector_dct[comp])) {
00086             int sign = vp56_rac_get_prob(c, model->vector_sig[comp]);
00087             di  = vp56_rac_get_prob(c, model->vector_pdi[comp][0]);
00088             di |= vp56_rac_get_prob(c, model->vector_pdi[comp][1]) << 1;
00089             delta = vp56_rac_get_tree(c, vp56_pva_tree,
00090                                       model->vector_pdv[comp]);
00091             delta = di | (delta << 2);
00092             delta = (delta ^ -sign) + sign;
00093         }
00094         if (!comp)
00095             vect->x = delta;
00096         else
00097             vect->y = delta;
00098     }
00099 }
00100 
00101 static void vp5_parse_vector_models(VP56Context *s)
00102 {
00103     VP56RangeCoder *c = &s->c;
00104     VP56Model *model = s->modelp;
00105     int comp, node;
00106 
00107     for (comp=0; comp<2; comp++) {
00108         if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][0]))
00109             model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
00110         if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][1]))
00111             model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
00112         if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][2]))
00113             model->vector_pdi[comp][0] = vp56_rac_gets_nn(c, 7);
00114         if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][3]))
00115             model->vector_pdi[comp][1] = vp56_rac_gets_nn(c, 7);
00116     }
00117 
00118     for (comp=0; comp<2; comp++)
00119         for (node=0; node<7; node++)
00120             if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][4 + node]))
00121                 model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
00122 }
00123 
00124 static int vp5_parse_coeff_models(VP56Context *s)
00125 {
00126     VP56RangeCoder *c = &s->c;
00127     VP56Model *model = s->modelp;
00128     uint8_t def_prob[11];
00129     int node, cg, ctx;
00130     int ct;    /* code type */
00131     int pt;    /* plane type (0 for Y, 1 for U or V) */
00132 
00133     memset(def_prob, 0x80, sizeof(def_prob));
00134 
00135     for (pt=0; pt<2; pt++)
00136         for (node=0; node<11; node++)
00137             if (vp56_rac_get_prob(c, vp5_dccv_pct[pt][node])) {
00138                 def_prob[node] = vp56_rac_gets_nn(c, 7);
00139                 model->coeff_dccv[pt][node] = def_prob[node];
00140             } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
00141                 model->coeff_dccv[pt][node] = def_prob[node];
00142             }
00143 
00144     for (ct=0; ct<3; ct++)
00145         for (pt=0; pt<2; pt++)
00146             for (cg=0; cg<6; cg++)
00147                 for (node=0; node<11; node++)
00148                     if (vp56_rac_get_prob(c, vp5_ract_pct[ct][pt][cg][node])) {
00149                         def_prob[node] = vp56_rac_gets_nn(c, 7);
00150                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
00151                     } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
00152                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
00153                     }
00154 
00155     /* coeff_dcct is a linear combination of coeff_dccv */
00156     for (pt=0; pt<2; pt++)
00157         for (ctx=0; ctx<36; ctx++)
00158             for (node=0; node<5; node++)
00159                 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);
00160 
00161     /* coeff_acct is a linear combination of coeff_ract */
00162     for (ct=0; ct<3; ct++)
00163         for (pt=0; pt<2; pt++)
00164             for (cg=0; cg<3; cg++)
00165                 for (ctx=0; ctx<6; ctx++)
00166                     for (node=0; node<5; node++)
00167                         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);
00168     return 0;
00169 }
00170 
00171 static void vp5_parse_coeff(VP56Context *s)
00172 {
00173     VP56RangeCoder *c = &s->c;
00174     VP56Model *model = s->modelp;
00175     uint8_t *permute = s->scantable.permutated;
00176     uint8_t *model1, *model2;
00177     int coeff, sign, coeff_idx;
00178     int b, i, cg, idx, ctx, ctx_last;
00179     int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
00180 
00181     for (b=0; b<6; b++) {
00182         int ct = 1;    /* code type */
00183 
00184         if (b > 3) pt = 1;
00185 
00186         ctx = 6*s->coeff_ctx[vp56_b6to4[b]][0]
00187               + s->above_blocks[s->above_block_idx[b]].not_null_dc;
00188         model1 = model->coeff_dccv[pt];
00189         model2 = model->coeff_dcct[pt][ctx];
00190 
00191         coeff_idx = 0;
00192         for (;;) {
00193             if (vp56_rac_get_prob(c, model2[0])) {
00194                 if (vp56_rac_get_prob(c, model2[2])) {
00195                     if (vp56_rac_get_prob(c, model2[3])) {
00196                         s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 4;
00197                         idx = vp56_rac_get_tree(c, vp56_pc_tree, model1);
00198                         sign = vp56_rac_get(c);
00199                         coeff = vp56_coeff_bias[idx+5];
00200                         for (i=vp56_coeff_bit_length[idx]; i>=0; i--)
00201                             coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i;
00202                     } else {
00203                         if (vp56_rac_get_prob(c, model2[4])) {
00204                             coeff = 3 + vp56_rac_get_prob(c, model1[5]);
00205                             s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 3;
00206                         } else {
00207                             coeff = 2;
00208                             s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 2;
00209                         }
00210                         sign = vp56_rac_get(c);
00211                     }
00212                     ct = 2;
00213                 } else {
00214                     ct = 1;
00215                     s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 1;
00216                     sign = vp56_rac_get(c);
00217                     coeff = 1;
00218                 }
00219                 coeff = (coeff ^ -sign) + sign;
00220                 if (coeff_idx)
00221                     coeff *= s->dequant_ac;
00222                 s->block_coeff[b][permute[coeff_idx]] = coeff;
00223             } else {
00224                 if (ct && !vp56_rac_get_prob(c, model2[1]))
00225                     break;
00226                 ct = 0;
00227                 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 0;
00228             }
00229             coeff_idx++;
00230             if (coeff_idx >= 64)
00231                 break;
00232 
00233             cg = vp5_coeff_groups[coeff_idx];
00234             ctx = s->coeff_ctx[vp56_b6to4[b]][coeff_idx];
00235             model1 = model->coeff_ract[pt][ct][cg];
00236             model2 = cg > 2 ? model1 : model->coeff_acct[pt][ct][cg][ctx];
00237         }
00238 
00239         ctx_last = FFMIN(s->coeff_ctx_last[vp56_b6to4[b]], 24);
00240         s->coeff_ctx_last[vp56_b6to4[b]] = coeff_idx;
00241         if (coeff_idx < ctx_last)
00242             for (i=coeff_idx; i<=ctx_last; i++)
00243                 s->coeff_ctx[vp56_b6to4[b]][i] = 5;
00244         s->above_blocks[s->above_block_idx[b]].not_null_dc = s->coeff_ctx[vp56_b6to4[b]][0];
00245     }
00246 }
00247 
00248 static void vp5_default_models_init(VP56Context *s)
00249 {
00250     VP56Model *model = s->modelp;
00251     int i;
00252 
00253     for (i=0; i<2; i++) {
00254         model->vector_sig[i] = 0x80;
00255         model->vector_dct[i] = 0x80;
00256         model->vector_pdi[i][0] = 0x55;
00257         model->vector_pdi[i][1] = 0x80;
00258     }
00259     memcpy(model->mb_types_stats, vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
00260     memset(model->vector_pdv, 0x80, sizeof(model->vector_pdv));
00261 }
00262 
00263 static av_cold int vp5_decode_init(AVCodecContext *avctx)
00264 {
00265     VP56Context *s = avctx->priv_data;
00266 
00267     ff_vp56_init(avctx, 1, 0);
00268     s->vp56_coord_div = vp5_coord_div;
00269     s->parse_vector_adjustment = vp5_parse_vector_adjustment;
00270     s->parse_coeff = vp5_parse_coeff;
00271     s->default_models_init = vp5_default_models_init;
00272     s->parse_vector_models = vp5_parse_vector_models;
00273     s->parse_coeff_models = vp5_parse_coeff_models;
00274     s->parse_header = vp5_parse_header;
00275 
00276     return 0;
00277 }
00278 
00279 AVCodec ff_vp5_decoder = {
00280     "vp5",
00281     AVMEDIA_TYPE_VIDEO,
00282     CODEC_ID_VP5,
00283     sizeof(VP56Context),
00284     vp5_decode_init,
00285     NULL,
00286     ff_vp56_free,
00287     ff_vp56_decode_frame,
00288     CODEC_CAP_DR1,
00289     .long_name = NULL_IF_CONFIG_SMALL("On2 VP5"),
00290 };

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