+/*! ========================================================================
+** Extended Template Library
+** Box Blur Template Implementation
+** $Id$
+**
+** Copyright (c) 2002 Robert B. Quattlebaum Jr.
+**
+** This package is free software; you can redistribute it and/or
+** modify it under the terms of the GNU General Public License as
+** published by the Free Software Foundation; either version 2 of
+** the License, or (at your option) any later version.
+**
+** This package is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+** General Public License for more details.
+**
+** === N O T E S ===========================================================
+**
+** This is an internal header file, included by other ETL headers.
+** You should not attempt to use it directly.
+**
+** ========================================================================= */
+
+/* === S T A R T =========================================================== */
+
+#ifndef __ETL_BOXBLUR_H
+#define __ETL_BOXBLUR_H
+
+/* === H E A D E R S ======================================================= */
+
+/* === M A C R O S ========================================================= */
+
+/* === T Y P E D E F S ===================================================== */
+
+/* === C L A S S E S & S T R U C T S ======================================= */
+
+_ETL_BEGIN_NAMESPACE
+
+template<typename T1,typename T2> void
+hbox_blur(T1 pen,int w, int h, int length, T2 outpen)
+{
+ int x,y;
+ typename T1::iterator_x iter, end;
+
+ length=std::min(w,length);
+ const float divisor(1.0f/(length*2+1));
+
+ for(y=0;y<h;y++,pen.inc_y(),outpen.inc_y())
+ {
+ iter=pen.x();
+ end=pen.end_x();
+
+ typename T1::accumulator_type tot(*iter*(length+1));
+
+ for (x=0;x<length && iter!=end;x++,++iter) tot+=*iter;
+ iter=pen.x();
+
+ for (x=0;x<w && iter!=end;x++,++iter,outpen.inc_x())
+ {
+ tot -= (x>length) ? iter[-length-1] : *pen.x();
+ tot += ((x+length)<w) ? iter[length] : end[-1];
+
+ outpen.put_value(tot*divisor);
+ }
+ outpen.dec_x(x);
+ }
+}
+
+#if 1
+template<typename T1,typename T2> void
+vbox_blur(T1 pen,const int w, const int h, int length, T2 outpen)
+{
+ int x,y;
+ typename T1::iterator_y iter, end;
+
+ length=std::min(h,length);
+ const float divisor(1.0f/(length*2+1));
+
+ for(x=0;x<w;x++,pen.inc_x(),outpen.inc_x())
+ {
+ iter=pen.y();
+ end=pen.end_y();
+
+ typename T1::accumulator_type tot(*iter*(length+1));
+
+ for (y=0;y<length && iter!=end;y++,++iter) tot+=*iter;
+ iter=pen.y();
+
+ for (y=0;y<h && iter!=end;y++,++iter,outpen.inc_y())
+ {
+ tot -= (y>length) ? iter[-length-1] : *pen.y();
+ tot += ((y+length)<h) ? iter[length] : end[-1];
+
+ outpen.put_value(tot*divisor);
+ }
+ outpen.dec_y(y);
+ }
+}
+
+#else
+
+template<typename T1,typename T2> void
+vbox_blur(T1 pen,int w, int h, int length,T2 outpen)
+{
+ int x,y;
+ typename T1::iterator_y iter, end, biter,eiter;
+
+ //print out the info I need to figure out if this is somehow a buffer overrun...
+ /*char *beginptr=0,*endptr=0;
+ {
+ T1 ypen = pen;
+ T1 endpen = pen;
+ endpen.move(w,h);
+ ypen.inc_y();
+
+ T2 open = outpen,
+ oepen = outpen;
+ oepen.move(w,h);
+ printf("V Blur (%d,%d,s-%d) in(%p,%p,st %d) out(%p,%p)\n",
+ w,h,length,(char*)pen.x(),(char*)endpen.x(),(char*)ypen.x()-(char*)pen.x(),
+ (char*)open.x(),(char*)oepen.x());
+ }*/
+ length=min(h-1,length);
+
+ const float divisor(1.0f/(length*2+1));
+ //const int div = (length*2+1);
+
+ //since the filter range is 2*length+1 we need h-1
+ for(x=0;x<w;x++,pen.inc_x(),outpen.inc_x())
+ {
+ iter=pen.y();
+ end=pen.end_y();
+
+ const typename T1::value_type bval = *iter;
+ const typename T1::value_type eval = end[-1];
+
+ typename T1::accumulator_type tot(bval*(length+1));
+ //beginptr = (char*)&*iter; endptr = (char*)&*end;
+
+ //printf("\nx line %d (%p,%p)\n",x,beginptr,endptr);
+
+ //printf("Init %.3f - ",tot);
+ for (y=0;y<length && iter!=end;y++)
+ {
+ tot+=iter[y];
+ //printf("(%d,%p,+%.3f->%.3f),",y,&iter[y],iter[y],tot);
+ }
+ iter=pen.y();
+
+ //printf(" tot=%.3f\n",tot);
+
+ biter = iter+(-length-1); //get the first one...
+ eiter = iter+length;
+
+ //y will always be > length
+ //T2 open = outpen;
+ for (y=0;y<h && iter!=end;y++,++iter,++biter,++eiter,outpen.inc_y())
+ {
+ //printf("y line %d - (%f) ",y,tot);
+
+ if (y>length)
+ {
+ typename T1::value_type &v = *biter;
+ /*if( (char*)&v < beginptr ||
+ (char*)&v >= endptr)
+ printf("crap! %d (%p off %p)\n",y,(char*)&v,(char*)&*iter);*/
+ tot -= v;
+ //printf("[%.3f,",v);
+ }
+ else
+ {
+ tot -= bval;
+ //printf("[%.3f,",bval);
+ }
+
+ if (y+length<h)
+ {
+ typename T1::value_type &v = *eiter;
+ /*if( (char*)&v < beginptr ||
+ (char*)&v >= endptr)
+ printf("crap! %d (%p off %p)\n",y,(char*)&v,(char*)&*iter);*/
+ tot += v;
+ //printf("%.3f]",v);
+ }
+ else
+ {
+ tot += eval;
+ //printf("%.3f]",eval);
+ }
+
+ //test handled in the previous case...
+ //tot -= (y>length) ? *biter : bval;
+ //tot += (y+length<h) ? *eiter : eval;
+
+ //printf(" - %.3f\n",tot);
+ outpen.put_value(tot*divisor);
+ }
+ outpen.dec_y(y);
+ }
+}
+#endif
+
+template<typename T1,typename T2> void
+box_blur(T1 pen,int w, int h, int blur_w, int blur_h, T2 outpen)
+ { hbox_blur(pen,w,h,blur_w,outpen); vbox_blur(pen,w,h,blur_h,outpen); }
+
+template<typename T1,typename T2> void
+box_blur(T1 pen,int w, int h, int size, T2 outpen)
+ { hbox_blur(pen,w,h,size,outpen); vbox_blur(pen,w,h,size,outpen); }
+
+template<typename T1,typename T2> void
+hbox_blur(T1 begin,T1 end, int len,T2 outpen)
+{
+ typename T1::difference_type size(end-begin);
+ hbox_blur(begin,size.x,size.y,len,outpen);
+}
+
+template<typename T1,typename T2> void
+vbox_blur(T1 begin,T1 end, int len,T2 outpen)
+{
+ typename T1::difference_type size(end-begin);
+ vbox_blur(begin,size.x,size.y,len,outpen);
+}
+
+template<typename T1,typename T2> void
+box_blur(T1 begin,T1 end, int blur_w, int blur_h,T2 outpen)
+{
+ typename T1::difference_type size(end-begin);
+ hbox_blur(begin,size.x,size.y,blur_w,outpen); vbox_blur(begin,size.x,size.y,blur_h,outpen);
+}
+
+template<typename T1,typename T2> void
+box_blur(T1 begin,T1 end, int blursize,T2 outpen)
+{
+ typename T1::difference_type size(end-begin);
+ hbox_blur(begin,size.x,size.y,blursize,outpen); vbox_blur(begin,size.x,size.y,blursize,outpen);
+}
+
+_ETL_END_NAMESPACE
+
+/* === E X T E R N S ======================================================= */
+
+/* === E N D =============================================================== */
+
+#endif