% PROBLEM 5.3
% ===========

% Load the image
imbase = ['../text/images/'];
gs = imread([imbase,'cameraman.tif']);   % Grayscale
A = double(gs);

% Speciay the different filters
Ha = [-1 -1 0 ; -1 0 1 ; 0 1 1];
Hb = [0 -1 -1 ; 1 0 -1 ; 1 1 0];
Hc = [-1 -1 -1 ; 2 2 2 ; -1 -1 -1];
Hd = [-1 2 -1 ; -1 2 -1 ; -1 2 -1];
He = [-1 -1 -1 ; -1 8 -1 ; -1 -1 -1];
Hf = [1 1 1 ; 1 1 1 ; 1 1 1];
Hg = [-1 0 1 ; -1 0 1 ; -1 0 1];
Hh = [0 -1 0 ; -1 4 -1 ; 0 -1 0];

% Do the filtering
Ya = filter2(Ha,A);
Yb = filter2(Hb,A);
Yc = filter2(Hc,A);
Yd = filter2(Hd,A);
Ye = filter2(He,A);
Yf = filter2(Hf,A);
Yg = filter2(Hg,A);
Yh = filter2(Hh,A);

% Plot the results
figure(1);clf;colormap gray
subplot(331);imagesc(A);title('Original image');
colorbar
subplot(332);imagesc(Ya);title('Filter a: 45 degree edges');
colorbar
subplot(333);imagesc(Yb);title('Filter b: -45 degree edges');
colorbar
subplot(334);imagesc(Yc);title('Filter c: Horizontal edges');
colorbar
subplot(335);imagesc(Yd);title('Filter d: Vertical edges');
colorbar
subplot(336);imagesc(Ye);title('Filter e: Laplacian');
colorbar
subplot(337);imagesc(Yf);title('Filter f: Smoothing');
colorbar
subplot(338);imagesc(Yg);title('Filter g Vertical edges');
colorbar
subplot(339);imagesc(Yh);title('Filter h: Laplacian');
colorbar
print -djpeg p5p3.jpg

clear all


% PROBLEM 5.10
% ============
imbase = ['../text/images/'];
% Cameraman image
gs = imread([imbase,'cameraman.tif']);   % Grayscale
A = double(gs);
% Mandrill image
load('mandrill.mat');
B = im2uint8(ind2gray(X,map));

figure(1);clf;colormap(gray);
figure(2);clf;colormap(gray);

alpha = linspace(0,1,9);
for idx = 1:length(alpha)
  h = fspecial('laplacian',alpha(idx));
  fa = filter2(h,A,'same');
  fb = filter2(h,B,'same');
  
  figure(1);subplot(3,3,idx);
  imagesc(fa);title(['Laplacian \alpha= ',num2str(alpha(idx))])
  figure(2);subplot(3,3,idx);
  imagesc(fb);title(['Laplacian \alpha= ',num2str(alpha(idx))])
end
figure(1);print -djpeg p5p10_lap_cam.jpg
figure(2);print -djpeg p5p10_lap_man.jpg

figure(1);clf;colormap(gray);
figure(2);clf;colormap(gray);
hsize = [3 7 11];
sig = [.1 1 10];
cnt = 1;
for idx1 = 1:length(hsize)
  for idx2 = 1:length(sig)
    h = fspecial('log',hsize(idx1),sig(idx2));
    fa = filter2(h,A,'same');
    fb = filter2(h,B,'same');
    
    figure(1);subplot(3,3,cnt);
    imagesc(fa);
    title(['LoG size = ',num2str(hsize(idx1)),' \sigma = ',num2str(sig(idx2))])
    figure(2);subplot(3,3,cnt);
    imagesc(fb);
    title(['LoG size = ',num2str(hsize(idx1)),' \sigma = ',num2str(sig(idx2))])
    cnt = cnt+1;
  end
end
figure(1);print -djpeg p5p10_log_cam.jpg
figure(2);print -djpeg p5p10_log_man.jpg

% PROBLEM 5.18
% ============
% Cameraman image
gs = imread([imbase,'cameraman.tif']);   % Grayscale
gs = double(gs);
% Do the blur
b = ones(3)/9;
gs1 = filter2(b,gs,'same');

% Do the unsharp mask
usm = fspecial('unsharp',.9);
gs2 = filter2(usm,gs1,'same');

% Plot the results
figure(1);clf;colormap(gray);
subplot(131);imagesc(gs(30:100,90:160));title('Original');axis square
subplot(132);imagesc(gs1(30:100,90:160));title('Blurred');axis square
subplot(133);imagesc(gs2(30:100,90:160));title('After unsharp masking');axis square

print -djpeg p5p18.jpg