How to shear an imagesc image

Hi,

I have an image, created using imagesc function from a data matrix, like so:

imagesc (myarray, [-50 0]);

which I am then trying to shear by an angle a using the following code:

a = tand(10); 
T = maketform('affine', [1 0 0; a 1 0; 0 0 1] );
B = imtransform(A,T,'cubic','FillValues',orange);
orange = [255 127 0]';
figure
imshow(B)

But I keep on failing, as I guess I'm not defining A (my original image created using imagesc) correctly.

Could anyone please explain how to define it correctly so it works as an input for the imtransform function?

Thank you.

[KSSV]

What error you are getting? You must specify you error along with full code.

[Linda Toca]

Well, if I define A as A= imagesc (myarray, [-50 0]); and the try to to run B, i get:

Error using imtransform>check_A (line 479)

A must be a nonsparse numeric array.

Error in imtransform>parse_inputs (line 373)

args.A = check_A(varargin{1});

Error in imtransform (line 266)

args = parse_inputs(varargin{:});

So I know the problem probably lies in how I define the A

Answer 1

[Pranjal Kaura]

Hey Linda,

Using functions 'imtransform' and 'maketform' is not recommended because of compatibilty considerations. You can use 'imwarp' and 'affine2d' instead. Here's a code snippet addressing the changes

a = tand(10); 
T = affine2d( [1 0 0; a 1 0; 0 0 1] );
B = imwarp(img,T,'cubic','FillValues',0);

Could you share more information regarding your usecase and why you need 'imagesc' function? Also the complete code, wherein you're defining 'A'.