/* this is a butchered version of derf's theora-exp code */ void quant_tables_init(oc_quant_table *_quant[2][3], const th_quant_info *_qinfo){ int qti; int pli; for(qti=0;qti<2;qti++)for(pli=0;pli<3;pli++){ int qi; int qri; /*These simple checks help us improve cache coherency later.*/ if(pli>0&&memcmp(_qinfo->qi_ranges[qti]+pli-1, _qinfo->qi_ranges[qti]+pli,sizeof(_qinfo->qi_ranges[qti][pli]))==0){ _quant[qti][pli]=_quant[qti][pli-1]; continue; } if(qti>0&&memcmp(_qinfo->qi_ranges[qti-1]+pli, _qinfo->qi_ranges[qti]+pli,sizeof(_qinfo->qi_ranges[qti][pli]))==0){ _quant[qti][pli]=_quant[qti-1][pli]; continue; } for(qi=qri=0;qri<=_qinfo->qi_ranges[qti][pli].nranges;qri++){ th_quant_base base; ogg_uint32_t q; int qi_start; int qi_end; int ci; memcpy(base,_qinfo->qi_ranges[qti][pli].base_matrices[qri], sizeof(base)); qi_start=qi; if(qri==_qinfo->qi_ranges[qti][pli].nranges)qi_end=qi+1; else qi_end=qi+_qinfo->qi_ranges[qti][pli].sizes[qri]; for(;;){ ogg_uint32_t qfac; /*In the original VP3.2 code, the rounding offset and the size of the dead zone around 0 were controlled by a "sharpness" parameter. The size of our dead zone is now controlled by the per-coefficient quality thresholds returned by our HVS module. We round down from a more accurate value when the quality of the reconstruction does not fall below our threshold and it saves bits. Hence, all of that VP3.2 code is gone from here, and the remaining floating point code has been implemented as equivalent integer code with exact precision.*/ /*Scale DC the coefficient from the proper table.*/ /*qfac=(ogg_uint32_t)_qinfo->dc_scale[qi]*base[0];*/ qfac=base[0]; /*q=(qfac/100)<<2;*/ q=OC_CLAMPI(OC_DC_QUANT_MIN[qti],q,OC_QUANT_MAX); _quant[qti][pli][qi][0]=(ogg_uint16_t)q; /*Now scale AC coefficients from the proper table.*/ for(ci=1;ci<64;ci++){ /*q=((ogg_uint32_t)_qinfo->ac_scale[qi]*base[ci]/100)<<2;*/ q=base[ci]; q=OC_CLAMPI(OC_AC_QUANT_MIN[qti],q,OC_QUANT_MAX); _quant[qti][pli][qi][ci]=(ogg_uint16_t)q; } if(++qi>=qi_end)break; /*Interpolate the next base matrix.*/ for(ci=0;ci<64;ci++){ base[ci]=(unsigned char)( (2*((qi_end-qi)*_qinfo->qi_ranges[qti][pli].base_matrices[qri][ci]+ (qi-qi_start)*_qinfo->qi_ranges[qti][pli].base_matrices[qri+1][ci]) +_qinfo->qi_ranges[qti][pli].sizes[qri])/ (2*_qinfo->qi_ranges[qti][pli].sizes[qri])); } } } } }