source: issm/trunk-jpl/src/m/contrib/morlighem/modeldata/interpFromGeotiff.m@ 23876

function dataout = interpFromGeotiff(geotiffname,X,Y),

usemap = 0;
if license('test','map_toolbox')==0,
        disp('WARNING: map toolbox not installed, trying house code');
        usemap = 0;
elseif license('checkout','map_toolbox')==0
        disp('WARNING: map toolbox not available (checkout failed), trying house code');
        usemap = 0;
end

if usemap,
        [data,R] = geotiffread(geotiffname);
        data=double(flipud(data));
        xdata=R.XLimWorld(1):R.DeltaX:R.XLimWorld(2); xdata=xdata(:);
        xdata =(xdata(1:end-1)+xdata(2:end))/2;
        ydata=R.YLimWorld(2):R.DeltaY:R.YLimWorld(1); ydata=flipud(ydata(:));
        ydata =(ydata(1:end-1)+ydata(2:end))/2;
else

        %Get image info
        Tinfo = imfinfo(geotiffname);
        N     = Tinfo.Width;
        M     = Tinfo.Height;
        dx    = Tinfo.ModelPixelScaleTag(1);
        dy    = Tinfo.ModelPixelScaleTag(2);
        minx  = Tinfo.ModelTiepointTag(4);
        maxy  = Tinfo.ModelTiepointTag(5);

        %Generate vectors
        xdata = minx + dx/2 + ((0:N-1).*dx);
        ydata = maxy - dy/2 - ((M  -1:-1:0).*dy);

        %Read image
        data=double(flipud(imread(geotiffname)));
        data(find(abs(data)>10^30))=NaN;
end

dataout = InterpFromGrid(xdata,ydata,data,X,Y);
dataout(dataout==-9999)=NaN;