function?im_ext?=?bound_extension（imByBxtype）

%?im_ext?=?bound_extension（imBtype）;
%
%?Extend?an?image?for?avoiding?boundary?artifacts
%
%???By?Bx:????widths?of?the?added?stripes.
%???type:???‘mirror‘????????Mirror?extension
%???????????‘mirror_nr‘:????Mirror?without?repeating?the?last?pixel
%???????????‘circular‘:?????fft2-like
%???????????‘zeros‘

%?Javier?Portilla?Universidad?de?Granada?Jan?2004

[NyNxNc]?=?size（im）;

im_ext?=?zeros（Ny+2*ByNx+2*BxNc）;
im_ext（By+1:Ny+ByBx+1:Nx+Bx:）?=?im;

if?strcmp（type‘mirror‘）

????im_ext（1:By::）?=?im_ext（2*By:-1:By+1::）;
????im_ext（:1:Bx:）?=?im_ext（:2*Bx:-1:Bx+1:）;
????im_ext（Ny+1+By:Ny+2*By::）?=?im_ext（Ny+By:-1:Ny+1::）;
????im_ext（:Nx+1+Bx:Nx+2*Bx:）?=?im_ext（:Nx+Bx:-1:Nx+1:）;
????im_ext（1:By1:Bx:）?=?im_ext（2*By:-1:By+12*Bx:-1:Bx+1:）;
????im_ext（Ny+1+By:Ny+2*ByNx+1+Bx:Nx+2*Bx:）?=?im_ext（Ny+By:-1:Ny+1Nx+Bx:-1:Nx+1:）;
????im_ext（1:ByNx+1+Bx:Nx+2*Bx:）?=?im_ext（2*By:-1:By+1Nx+Bx:-1:Nx+1:）;
????im_ext（Ny+1+By:Ny+2*By1:Bx:）?=?im_ext（Ny+By:-1:Ny+12*Bx:-1:Bx+1:）;

elseif?strcmp（type‘mirror_nr‘）????
????????
????im_ext（1:By::）?=?im_ext（2*By+1:-1:By+2::）;
????im_ext（:1:Bx:）?=?im_ext（:2*Bx+1:-1:Bx+2:）;
????im_ext（Ny+1+By:Ny+2*By::）?=?im_ext（Ny+By-1:-1:Ny::）;
????im_ext（:Nx+1+Bx:Nx+2*Bx:）?=?im_ext（:Nx+Bx-1:-1:Nx:）;
????im_ext（1:By1:Bx:）?=?im_ext（2*By+1:-1:By+22*Bx+1:-1:Bx+2:）;
????im_ext（Ny+1+By:Ny+2*ByNx+1+Bx:Nx+2*Bx:）?=?im_ext（Ny+By-1:-1:NyNx+Bx-1:-1:Nx:）;
????im_ext（1:ByNx+1+Bx:Nx+2*Bx:）?=?im_ext（2*By+1:-1:By+2Nx+Bx-1:-1:Nx:）;
????im_ext（Ny+1+By:Ny+2*By1:Bx:）?=?im_ext（Ny+By-1:-1:Ny2*Bx+1:-1:Bx+2:）;
????????
elseif?strcmp（type‘circular‘）????????
????????
????im_ext（1:By::）?=??im_ext（Ny+1:Ny+By::）;
????im_ext（:1:Bx:）?=?im_ext（:Nx+1:Nx+Bx:）;
????im_ext（Ny+1+By:Ny+2*By::）?=?im_ext（By+1:2*By::）;
????im_ext（:Nx+1+Bx:Nx+2*Bx:）?=?im_ext（:Bx+1:2*Bx:）;
????im_ext（1:By1:Bx:）?=?im_ext（Ny+1:Ny+ByNx+1:Nx+Bx:）;
????im_ext（Ny+1+By:Ny+2*ByNx+1+Bx:Nx+2*Bx:）?=?im_ext（By+1:2*ByBx+1:2*Bx:）;
????im_ext（1:ByNx+1+Bx:Nx+2*Bx:）?=?im_ext（Ny+1:Ny+ByBx+1:2*Bx:）;
????im_ext（Ny+1+By:Ny+2*By1:Bx:）?=?im_ext（By+1:2*ByNx+1:Nx+Bx:）;
???
end????
????????

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----
?????文件????????2254??2008-11-18?14:31??bound_extension.m
?????文件???????16812??2010-06-14?14:53??nlmeans_lnla2008_goossens.m
?????文件????????3364??2010-06-14?13:53??psdnoise.m
?????文件??????269256??2005-07-23?12:18??barbara_big.tif
?????文件?????????335??2006-04-07?20:43??GetPSNR.m