integralImage3() - Image Processing

J = integralImage3(I) calculates
the integral image, J, from the input intensity
image, I.

Syntax

J = integralImage3(I) example

Example

Compute Integral Image of 3-D Input ImageOpen This Example
Create a 3-D input image.I = reshape(1:125,5,5,5);
Define a 3-by-3-by-3 sub-volume as [startRow, startCol, startPlane, endRow, endCol, endPlane].[sR, sC, sP, eR, eC, eP] = deal(2, 2, 2, 4, 4, 4);
Create an integral image from the input image and compute the sum over a 3-by-3-by-3 sub-volume of I.J = integralImage3(I);
regionSum = J(eR+1,eC+1,eP+1) - J(eR+1,eC+1,sP) - J(eR+1,sC,eP+1) ...
        - J(sR,eC+1,eP+1) + J(sR,sC,eP+1) + J(sR,eC+1,sP) ...
        + J(eR+1,sC,sP) -J(sR,sC,sP)

regionSum =

        1701

Verify that the sum of pixels is accurate.sum(sum(sum(I(sR:eR, sC:eC, sP:eP))))

ans =

        1701

Output / Return Value

Limitations

Alternatives / See Also

Reference