int oc_enc_quantize_c(ogg_int16_t _qdct[64],const ogg_int16_t _dct[64],
const ogg_uint16_t _dequant[64],const void *_enquant){
const oc_iquant *enquant;
int nonzero;
int zzi;
int val;
int d;
int s;
enquant=(const oc_iquant *)_enquant;
nonzero=0;
for(zzi=0;zzi<64;zzi++){
val=_dct[zzi];
d=_dequant[zzi];
val=val<<1;
if(abs(val)>=d){
s=OC_SIGNMASK(val);
/*The bias added here rounds ties away from zero, since token
optimization can only decrease the magnitude of the quantized
value.*/
val+=d+s^s;
/*Note the arithmetic right shift is not guaranteed by ANSI C.
Hopefully no one still uses ones-complement architectures.*/
val=((enquant[zzi].m*(ogg_int32_t)val>>16)+val>>enquant[zzi].l)-s;
_qdct[zzi]=(ogg_int16_t)val;
nonzero=zzi;
}
else _qdct[zzi]=0;
/*Search for the quantizer that matches the target most closely.
We don't assume a linear ordering, but when there are ties we pick the
quantizer closest to the old one.*/
static int oc_enc_find_qi_for_target(oc_enc_ctx *_enc,int _qti,int _qi_old,
int _qi_min,ogg_int64_t _log_qtarget){
ogg_int64_t best_qdiff;
int best_qi;
int qi;
best_qi=_qi_min;
best_qdiff=_enc->log_qavg[_qti][best_qi]-_log_qtarget;
best_qdiff=best_qdiff+OC_SIGNMASK(best_qdiff)^OC_SIGNMASK(best_qdiff);
for(qi=_qi_min+1;qi<64;qi++){
ogg_int64_t qdiff;
qdiff=_enc->log_qavg[_qti][qi]-_log_qtarget;
qdiff=qdiff+OC_SIGNMASK(qdiff)^OC_SIGNMASK(qdiff);
if(qdiff<best_qdiff||
qdiff==best_qdiff&&abs(qi-_qi_old)<abs(best_qi-_qi_old)){
best_qi=qi;
best_qdiff=qdiff;
}
}
return best_qi;
}
