1 files changed, 49 insertions, 0 deletions

diff --git a/SD-VBS/common/toolbox/toolbox_basic/affine/m_interp4.m b/SD-VBS/common/toolbox/toolbox_basic/affine/m_interp4.m
new file mode 100755
index 0000000..314f140
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+++ b/SD-VBS/common/toolbox/toolbox_basic/affine/m_interp4.m
@@ -0,0 +1,49 @@
+function [F,mask] = m_interp4(z,s,t)
+%INTERP4 2-D bilinear data interpolation.
+%       ZI = INTERP4(Z,XI,YI) assumes X = 1:N and Y = 1:M, where
+%       [M,N] = SIZE(Z).
+%
+%       Copyright (c) 1984-93 by The MathWorks, Inc.
+%       Clay M. Thompson 4-26-91, revised 7-3-91, 3-22-93 by CMT.
+%
+%  modified to 
+
+ 
+[nrows,ncols] = size(z);
+
+
+if any(size(z)<[3 3]), error('Z must be at least 3-by-3.'); end
+if size(s)~=size(t), error('XI and YI must be the same size.'); end
+
+% Check for out of range values of s and set to 1
+sout = find((s<1)|(s>ncols));
+if length(sout)>0, s(sout) = ones(size(sout)); end
+
+% Check for out of range values of t and set to 1
+tout = find((t<1)|(t>nrows));
+if length(tout)>0, t(tout) = ones(size(tout)); end
+
+% Matrix element indexing
+ndx = floor(t)+floor(s-1)*nrows;
+
+% Compute intepolation parameters, check for boundary value.
+d = find(s==ncols); 
+s(:) = (s - floor(s));
+if length(d)>0, s(d) = s(d)+1; ndx(d) = ndx(d)-nrows; end
+
+% Compute intepolation parameters, check for boundary value.
+d = find(t==nrows);
+t(:) = (t - floor(t));
+if length(d)>0, t(d) = t(d)+1; ndx(d) = ndx(d)-1; end
+d = [];
+
+% Now interpolate, reuse u and v to save memory.
+F =  ( z(ndx).*(1-t) + z(ndx+1).*t ).*(1-s) + ...
+     ( z(ndx+nrows).*(1-t) + z(ndx+(nrows+1)).*t ).*s;
+
+mask = ones(size(z));
+
+% Now set out of range values to zeros.
+if length(sout)>0, F(sout) = zeros(size(sout));mask(sout)=zeros(size(sout));end
+if length(tout)>0, F(tout) = zeros(size(tout));mask(tout)=zeros(size(tout));end
+