Latest version of the MATLAB function

the function img2data converts a .jpg, .png, etc. image to data and the
residuals of this data when fit to a straight line.

Author: johnharveybc

matlab/img2data.m

@@ -0,0 +1,54 @@
+function [ residual, y ] = img2data (x)
+
+gray = rgb2gray( x );
+BW = edge( gray );
+
+[height, width] = size(BW);
+y = zeros(1, width);
+residual = zeros(1, width);
+
+% for i = 1:width
+%     if max(BW(:, i)) > 0
+%         val = 0;
+%         count = 0;
+%         for j = 1: height   
+%             if BW(j,i) == 1
+%                 val = val + j;
+%                 count = count + 1;
+%             end
+%         end
+%         BW(:,i) = zeros(height, 1);
+%         val = round((val/count));
+%         BW(val, i) = 1;
+%     end
+% end
+
+imshowpair(gray,BW,'falsecolor')
+
+SE = strel('line', 4, 0);
+BWprime=imclose(BW, SE);
+      
+imshowpair(gray,BWprime,'falsecolor')
+
+for i = 1:width
+    for j = 0:height-1
+        if BWprime(height-j,i) == 1
+            y(1,i) = (j);
+        end
+    end
+end
+
+t = 1:width;
+z = zeros(1, width);
+c = fit (t', y', 'poly1');
+
+coeffs = coeffvalues(c);
+
+slope = coeffs(1);
+intercept = coeffs(2);
+
+for k = 1:width
+    residual(1,k) = y(1,k) - ( slope * k + intercept );
+end
+
+plot (t, residual, t, z)