/*% cyntax % -lfb && cc -go # % -lfb * Bayer-Powell noise removal filter. * If the average of the neighbors differs from * the center by more than 64, replace the center * with the average of the nieghbors. */#include "filter.cc"void filter(unsigned char *l0, unsigned char *l1, unsigned char *l2, int nchan, int npix){	unsigned char *op=outline;	int periph, eps;	npix*=nchan;	if(npix==0) return;	do{		periph=l0[-nchan]+l0[0]+l0[nchan]		      +l1[-nchan]      +l1[nchan]		      +l2[-nchan]+l2[0]+l2[nchan];		eps=periph-8*l1[0];		if(eps<0) eps=-eps;		*op++=eps>64*8?periph>>3:l1[0];		l0++;		l1++;		l2++;	}while(--npix!=0);}