Integral image c

1. What is the integral of an image?
2. What are integral images used for?
3. How to calculate integral image in matlab?

What is the integral of an image?

In an integral image, every pixel is the summation of the pixels above and to the left of it. To illustrate, the following shows and image and its corresponding integral image. The integral image is padded to the left and the top to allow for the calculation.

What are integral images used for?

An Integral image is where each pixel represents the cumulative sum of a corresponding input pixel with all pixels above and left of the input pixel. It enables rapid calculation of summations over image sub-regions. Any rectangular subset of such sub-region can be evaluated in constant time.

How to calculate integral image in matlab?

J = integralImage( I ) calculates the integral image from image I . The function zero-pads the top and left side of the output integral image, J . J = integralImage( I , orientation ) calculates the integral image with the orientation specified by orientation .