MATLAB: How to achieve a faster 3D Translation

Question

I'm making a GUI to allow a user to do image translation on set of 3D image data.

I want the user to be able to visually see the effects of the shift (using XY, XZ, and YZ slices).

I've tried this for 3D:

 % 3D transform:
    trslt   = [eye(3) xyz'; 0 0 0 1]';
    tform   = maketform('affine', trslt);
    data = tformarray(data, tform,  rsmp, [2 1 3], [2 1 3], sizXYZ([2 1 3]), [], 0);

However, performing the following 2D operations runs in a fraction of the time:

    xyTform = maketform('projective',[1 1; 1 sizY; sizX 1; sizX sizY],[1+x 1+y; 1+x sizY+y; sizX+x 1+y; sizX+x sizY+y]);
    zTform  = maketform('projective',[1 1; 1 sizY; sizZ 1; sizZ sizY],[1+z 1; 1+z sizY; sizZ+z 1; sizZ+z sizY]);
    data = tformarray(data, zTform,  rsmp, [3 1], [3 1], sizXYZ([3 1]), [], 0);
    data = tformarray(data, xyTform, rsmp, [2 1], [2 1], sizXYZ([2 1]), [], 0);

Is there any better (or faster) way to do this?

Edit: Just to clarify, I'm using this transform to allow shifting by "fractional" pixel amounts. I know this would be easier if shifting by whole pixels.

Answer 1

You may be able to get better speeds with griddedInterpolant(), especially if you have to do this multiple times at the same query points.