-static float _dist(int el,float *ref, float *b,int step){
- int i;
- float acc=0.f;
- for(i=0;i<el;i++){
- float val=(ref[i]-b[i*step]);
- acc+=val*val;
- }
- return(acc);
-}
-
-int _best(codebook *book, float *a, int step){
- encode_aux_threshmatch *tt=book->c->thresh_tree;
-
-#if 0
- encode_aux_nearestmatch *nt=book->c->nearest_tree;
- encode_aux_pigeonhole *pt=book->c->pigeon_tree;
-#endif
- int dim=book->dim;
- int k,o;
- /*int savebest=-1;
- float saverr;*/
-
- /* do we have a threshhold encode hint? */
- if(tt){
- int index=0,i;
- /* find the quant val of each scalar */
- for(k=0,o=step*(dim-1);k<dim;k++,o-=step){
-
- i=tt->threshvals>>1;
- if(a[o]<tt->quantthresh[i]){
-
- for(;i>0;i--)
- if(a[o]>=tt->quantthresh[i-1])
- break;
-
- }else{
-
- for(i++;i<tt->threshvals-1;i++)
- if(a[o]<tt->quantthresh[i])break;
-
- }
-
- index=(index*tt->quantvals)+tt->quantmap[i];
- }
- /* regular lattices are easy :-) */
- if(book->c->lengthlist[index]>0) /* is this unused? If so, we'll
- use a decision tree after all
- and fall through*/
- return(index);
- }
-
-#if 0
- /* do we have a pigeonhole encode hint? */
- if(pt){
- const static_codebook *c=book->c;
- int i,besti=-1;
- float best=0.f;
- int entry=0;
-
- /* dealing with sequentialness is a pain in the ass */
- if(c->q_sequencep){
- int pv;
- long mul=1;
- float qlast=0;
- for(k=0,o=0;k<dim;k++,o+=step){
- pv=(int)((a[o]-qlast-pt->min)/pt->del);
- if(pv<0 || pv>=pt->mapentries)break;
- entry+=pt->pigeonmap[pv]*mul;
- mul*=pt->quantvals;
- qlast+=pv*pt->del+pt->min;
- }
- }else{
- for(k=0,o=step*(dim-1);k<dim;k++,o-=step){
- int pv=(int)((a[o]-pt->min)/pt->del);
- if(pv<0 || pv>=pt->mapentries)break;
- entry=entry*pt->quantvals+pt->pigeonmap[pv];
- }
- }
-
- /* must be within the pigeonholable range; if we quant outside (or
- in an entry that we define no list for), brute force it */
- if(k==dim && pt->fitlength[entry]){
- /* search the abbreviated list */
- long *list=pt->fitlist+pt->fitmap[entry];
- for(i=0;i<pt->fitlength[entry];i++){
- float this=_dist(dim,book->valuelist+list[i]*dim,a,step);
- if(besti==-1 || this<best){
- best=this;
- besti=list[i];
- }
- }
-
- return(besti);
- }
- }
-
- if(nt){
- /* optimized using the decision tree */
- while(1){
- float c=0.f;
- float *p=book->valuelist+nt->p[ptr];
- float *q=book->valuelist+nt->q[ptr];
-
- for(k=0,o=0;k<dim;k++,o+=step)
- c+=(p[k]-q[k])*(a[o]-(p[k]+q[k])*.5);
-
- if(c>0.f) /* in A */
- ptr= -nt->ptr0[ptr];
- else /* in B */
- ptr= -nt->ptr1[ptr];
- if(ptr<=0)break;
- }
- return(-ptr);
- }
-#endif
-
- /* brute force it! */
- {
- const static_codebook *c=book->c;
- int i,besti=-1;
- float best=0.f;
- float *e=book->valuelist;
- for(i=0;i<book->entries;i++){
- if(c->lengthlist[i]>0){
- float this=_dist(dim,e,a,step);
- if(besti==-1 || this<best){
- best=this;
- besti=i;
- }
- }
- e+=dim;
- }
-
- /*if(savebest!=-1 && savebest!=besti){
- fprintf(stderr,"brute force/pigeonhole disagreement:\n"
- "original:");
- for(i=0;i<dim*step;i+=step)fprintf(stderr,"%g,",a[i]);
- fprintf(stderr,"\n"
- "pigeonhole (entry %d, err %g):",savebest,saverr);
- for(i=0;i<dim;i++)fprintf(stderr,"%g,",
- (book->valuelist+savebest*dim)[i]);
- fprintf(stderr,"\n"
- "bruteforce (entry %d, err %g):",besti,best);
- for(i=0;i<dim;i++)fprintf(stderr,"%g,",
- (book->valuelist+besti*dim)[i]);
- fprintf(stderr,"\n");
- }*/
- return(besti);
- }
-}
-