Own work.

Illustrates bilinear interpolation on the unit square. The four corners have fixed values as indicated in the figure, and the values in between are interpolated, and the interpolated values are represented by the colour.

Done in Matlab, source code:

# Grid of known points:
>> [X, Y] = meshgrid(0:1)
# Grid for interpolated values:
>> [XI,YI] = meshgrid(0:0.001:1);
# Known values to interpolate from:
>> Z = [0 1; 1 0.5]
# Do bilinear interpolation
>> ZI = interp2(X,Y,Z,XI,YI);
# Visualize result:
>> surf(XI,YI,ZI, 'EdgeColor','none'); alpha(0.9)
>> view([0 90])
>> print -dpng Bilininterp.png

• Image:BilinearInterpolExample.png

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