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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     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     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         vp56_rac_gets(c, 8);  /* number of displayed macroblock rows */
00059         vp56_rac_gets(c, 8);  /* number of displayed macroblock cols */
00060         vp56_rac_gets(c, 2);
00061         if (!s->macroblocks || /* first frame */
00062             16*cols != s->avctx->coded_width ||
00063             16*rows != s->avctx->coded_height) {
00064             avcodec_set_dimensions(s->avctx, 16*cols, 16*rows);
00065             return 2;
00066         }
00067     } else if (!s->macroblocks)
00068         return 0;
00069     return 1;
00070 }
00071 
00072 static void vp5_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
00073 {
00074     VP56RangeCoder *c = &s->c;
00075     VP56Model *model = s->modelp;
00076     int comp, di;
00077 
00078     for (comp=0; comp<2; comp++) {
00079         int delta = 0;
00080         if (vp56_rac_get_prob(c, model->vector_dct[comp])) {
00081             int sign = vp56_rac_get_prob(c, model->vector_sig[comp]);
00082             di  = vp56_rac_get_prob(c, model->vector_pdi[comp][0]);
00083             di |= vp56_rac_get_prob(c, model->vector_pdi[comp][1]) << 1;
00084             delta = vp56_rac_get_tree(c, vp56_pva_tree,
00085                                       model->vector_pdv[comp]);
00086             delta = di | (delta << 2);
00087             delta = (delta ^ -sign) + sign;
00088         }
00089         if (!comp)
00090             vect->x = delta;
00091         else
00092             vect->y = delta;
00093     }
00094 }
00095 
00096 static void vp5_parse_vector_models(VP56Context *s)
00097 {
00098     VP56RangeCoder *c = &s->c;
00099     VP56Model *model = s->modelp;
00100     int comp, node;
00101 
00102     for (comp=0; comp<2; comp++) {
00103         if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][0]))
00104             model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
00105         if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][1]))
00106             model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
00107         if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][2]))
00108             model->vector_pdi[comp][0] = vp56_rac_gets_nn(c, 7);
00109         if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][3]))
00110             model->vector_pdi[comp][1] = vp56_rac_gets_nn(c, 7);
00111     }
00112 
00113     for (comp=0; comp<2; comp++)
00114         for (node=0; node<7; node++)
00115             if (vp56_rac_get_prob(c, vp5_vmc_pct[comp][4 + node]))
00116                 model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
00117 }
00118 
00119 static void vp5_parse_coeff_models(VP56Context *s)
00120 {
00121     VP56RangeCoder *c = &s->c;
00122     VP56Model *model = s->modelp;
00123     uint8_t def_prob[11];
00124     int node, cg, ctx;
00125     int ct;    /* code type */
00126     int pt;    /* plane type (0 for Y, 1 for U or V) */
00127 
00128     memset(def_prob, 0x80, sizeof(def_prob));
00129 
00130     for (pt=0; pt<2; pt++)
00131         for (node=0; node<11; node++)
00132             if (vp56_rac_get_prob(c, vp5_dccv_pct[pt][node])) {
00133                 def_prob[node] = vp56_rac_gets_nn(c, 7);
00134                 model->coeff_dccv[pt][node] = def_prob[node];
00135             } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
00136                 model->coeff_dccv[pt][node] = def_prob[node];
00137             }
00138 
00139     for (ct=0; ct<3; ct++)
00140         for (pt=0; pt<2; pt++)
00141             for (cg=0; cg<6; cg++)
00142                 for (node=0; node<11; node++)
00143                     if (vp56_rac_get_prob(c, vp5_ract_pct[ct][pt][cg][node])) {
00144                         def_prob[node] = vp56_rac_gets_nn(c, 7);
00145                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
00146                     } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
00147                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
00148                     }
00149 
00150     /* coeff_dcct is a linear combination of coeff_dccv */
00151     for (pt=0; pt<2; pt++)
00152         for (ctx=0; ctx<36; ctx++)
00153             for (node=0; node<5; node++)
00154                 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);
00155 
00156     /* coeff_acct is a linear combination of coeff_ract */
00157     for (ct=0; ct<3; ct++)
00158         for (pt=0; pt<2; pt++)
00159             for (cg=0; cg<3; cg++)
00160                 for (ctx=0; ctx<6; ctx++)
00161                     for (node=0; node<5; node++)
00162                         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);
00163 }
00164 
00165 static void vp5_parse_coeff(VP56Context *s)
00166 {
00167     VP56RangeCoder *c = &s->c;
00168     VP56Model *model = s->modelp;
00169     uint8_t *permute = s->scantable.permutated;
00170     uint8_t *model1, *model2;
00171     int coeff, sign, coeff_idx;
00172     int b, i, cg, idx, ctx, ctx_last;
00173     int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
00174 
00175     for (b=0; b<6; b++) {
00176         int ct = 1;    /* code type */
00177 
00178         if (b > 3) pt = 1;
00179 
00180         ctx = 6*s->coeff_ctx[vp56_b6to4[b]][0]
00181               + s->above_blocks[s->above_block_idx[b]].not_null_dc;
00182         model1 = model->coeff_dccv[pt];
00183         model2 = model->coeff_dcct[pt][ctx];
00184 
00185         coeff_idx = 0;
00186         for (;;) {
00187             if (vp56_rac_get_prob(c, model2[0])) {
00188                 if (vp56_rac_get_prob(c, model2[2])) {
00189                     if (vp56_rac_get_prob(c, model2[3])) {
00190                         s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 4;
00191                         idx = vp56_rac_get_tree(c, vp56_pc_tree, model1);
00192                         sign = vp56_rac_get(c);
00193                         coeff = vp56_coeff_bias[idx+5];
00194                         for (i=vp56_coeff_bit_length[idx]; i>=0; i--)
00195                             coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i;
00196                     } else {
00197                         if (vp56_rac_get_prob(c, model2[4])) {
00198                             coeff = 3 + vp56_rac_get_prob(c, model1[5]);
00199                             s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 3;
00200                         } else {
00201                             coeff = 2;
00202                             s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 2;
00203                         }
00204                         sign = vp56_rac_get(c);
00205                     }
00206                     ct = 2;
00207                 } else {
00208                     ct = 1;
00209                     s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 1;
00210                     sign = vp56_rac_get(c);
00211                     coeff = 1;
00212                 }
00213                 coeff = (coeff ^ -sign) + sign;
00214                 if (coeff_idx)
00215                     coeff *= s->dequant_ac;
00216                 s->block_coeff[b][permute[coeff_idx]] = coeff;
00217             } else {
00218                 if (ct && !vp56_rac_get_prob(c, model2[1]))
00219                     break;
00220                 ct = 0;
00221                 s->coeff_ctx[vp56_b6to4[b]][coeff_idx] = 0;
00222             }
00223             coeff_idx++;
00224             if (coeff_idx >= 64)
00225                 break;
00226 
00227             cg = vp5_coeff_groups[coeff_idx];
00228             ctx = s->coeff_ctx[vp56_b6to4[b]][coeff_idx];
00229             model1 = model->coeff_ract[pt][ct][cg];
00230             model2 = cg > 2 ? model1 : model->coeff_acct[pt][ct][cg][ctx];
00231         }
00232 
00233         ctx_last = FFMIN(s->coeff_ctx_last[vp56_b6to4[b]], 24);
00234         s->coeff_ctx_last[vp56_b6to4[b]] = coeff_idx;
00235         if (coeff_idx < ctx_last)
00236             for (i=coeff_idx; i<=ctx_last; i++)
00237                 s->coeff_ctx[vp56_b6to4[b]][i] = 5;
00238         s->above_blocks[s->above_block_idx[b]].not_null_dc = s->coeff_ctx[vp56_b6to4[b]][0];
00239     }
00240 }
00241 
00242 static void vp5_default_models_init(VP56Context *s)
00243 {
00244     VP56Model *model = s->modelp;
00245     int i;
00246 
00247     for (i=0; i<2; i++) {
00248         model->vector_sig[i] = 0x80;
00249         model->vector_dct[i] = 0x80;
00250         model->vector_pdi[i][0] = 0x55;
00251         model->vector_pdi[i][1] = 0x80;
00252     }
00253     memcpy(model->mb_types_stats, vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
00254     memset(model->vector_pdv, 0x80, sizeof(model->vector_pdv));
00255 }
00256 
00257 static av_cold int vp5_decode_init(AVCodecContext *avctx)
00258 {
00259     VP56Context *s = avctx->priv_data;
00260 
00261     vp56_init(avctx, 1, 0);
00262     s->vp56_coord_div = vp5_coord_div;
00263     s->parse_vector_adjustment = vp5_parse_vector_adjustment;
00264     s->parse_coeff = vp5_parse_coeff;
00265     s->default_models_init = vp5_default_models_init;
00266     s->parse_vector_models = vp5_parse_vector_models;
00267     s->parse_coeff_models = vp5_parse_coeff_models;
00268     s->parse_header = vp5_parse_header;
00269 
00270     return 0;
00271 }
00272 
00273 AVCodec vp5_decoder = {
00274     "vp5",
00275     AVMEDIA_TYPE_VIDEO,
00276     CODEC_ID_VP5,
00277     sizeof(VP56Context),
00278     vp5_decode_init,
00279     NULL,
00280     vp56_free,
00281     vp56_decode_frame,
00282     CODEC_CAP_DR1,
00283     .long_name = NULL_IF_CONFIG_SMALL("On2 VP5"),
00284 };

Generated on Wed Dec 21 2011 18:44:11 for FFmpeg by  doxygen 1.7.1