Remove the unwanted region from an image and rotate it to 45 degree

I have an image attached with this question. I wanted to remove the unwanted white portion and rotate image to 45 degree angle. The unwanted portion contains values either 255 or 0. Please help me.

[KALYAN ACHARJYA]

Remove the unwanted region

What does it mean?

Remove the pixel?? Then what remains there?

Answer 1

[Image Analyst]

Try this:

grayImage = imread('11.bmp');
subplot(2, 2, 1);
imshow(grayImage)
title('Original Image', 'FontSize', 15);

grayImage = imrotate(grayImage, -45);
subplot(2, 2, 2);
imshow(grayImage)
title('Rotated Image', 'FontSize', 15);

% Get mask
mask = bwconvhull(grayImage ~= 255 & grayImage ~= 0);
subplot(2, 2, 3);
imshow(mask)
title('mask', 'FontSize', 15);

% Find cropping index
[rows, columns] = find(mask)
% Crop 
croppedImage = grayImage(min(rows):max(rows), min(columns):max(columns));
subplot(2, 2, 4);
imshow(croppedImage)
title('Cropped Image', 'FontSize', 15);

[ashwini patil]

Thats great..... Thank you ... Its working fine.... and thanks again for quick response...

[ashwini patil]

Same thing I was trying to do on attached image. I want only ridge region of the fingerprint from the image attached with this question. I wrote following program for that. But gives same image as output. Please help me.

grayImage = imread('123.bmp'); 
subplot(2, 2, 1); 
imshow(grayImage) 
title('Original Image', 'FontSize', 15); 
% grayImage = imrotate(grayImage, -45); 
% subplot(2, 2, 2); 
% imshow(grayImage) 
% title('Rotated Image', 'FontSize', 15); 
% Get mask 
mask = bwconvhull(grayImage ~= 252 & grayImage ~= 253 & grayImage ~= 255 ); 
subplot(2, 2, 3); 
imshow(mask) 
title('mask', 'FontSize', 15); 
% Find cropping index 
[rows, columns] = find(mask); 
% Crop 
croppedImage = grayImage(min(rows):max(rows), min(columns):max(columns)); 
subplot(2, 2, 4); 
figure,imshow(croppedImage) 
title('Cropped Image', 'FontSize', 15);

[ashwini patil]

Hello sir, Please help me.. I want the solution as early as possible.. I attached one image with this question. I want only region of interest of this image. Means I want to remove white portion from image. Please guide me.

[Image Analyst]

What do you want in place of the white? Because images cannot have ragged bottoms or sides - they MUST remain rectangular.

[ashwini patil]

Now in my project I have to compute energy and entropy of the above cropped Images. Can you please guide me that how should the energy and entropy of an image is calculated??