% NAME:
% test_get_intensity_interp_01.m
%
% DESC:
% test the interpolation routines

close all
clear all
clc

I = imread('cameraman.tif');

% create points on the patch
w = 16;
[xx yy] = ndgrid(-w:w, -w:w);
xx = transpose(xx(:));
yy = transpose(yy(:));

% map the patch ont the image
xx0 = 88;
yy0 = 158;
phi = 60*pi/180;
x(1, :) = xx0 + cos(phi)*xx - sin(phi)*yy;
x(2, :) = yy0 + sin(phi)*xx + cos(phi)*yy;

% interpolate
mode = 0;
Ii0 = get_intensity_interp(I, x, mode);
Ii0 = reshape(Ii0, 2*w+1, 2*w+1);

mode = 1;
Ii1 = get_intensity_interp(I, x, mode);
Ii1 = reshape(Ii1, 2*w+1, 2*w+1);

mode = 2;
Ii2 = get_intensity_interp(I, x, mode);
Ii2 = reshape(Ii2, 2*w+1, 2*w+1);

% display the results
figure;

pp = 1;
qq = 4;

subplot(pp, qq, 1);
imshow(I)
hold on
plot(x(2, :), x(1, :), '.r')

subplot(pp, qq, 2);
imshow(imscale(Ii0))
title('Nearest Neighbour')

subplot(pp, qq, 3);
imshow(imscale(Ii1))
title('Bilinear')

subplot(pp, qq, 4);
imshow(imscale(Ii2))
title('Cubic')