What is rolling ball in image processing?

The rolling-ball algorithm estimates the background intensity of a grayscale image in case of uneven exposure. It is frequently used in biomedical image processing and was first proposed by Stanley R. Sternberg in 1983 1. The algorithm works as a filter and is quite intuitive.

What is rolling ball background subtraction?

A local background value is determined for every pixel by averaging over a very large ball around the pixel. This value is hereafter subtracted from the original image, hopefully removing large spatial variations of the background intensities.

What is rolling ball radius?

The Rolling Ball Radius is the radius of curvature of the paraboloid. As a rule of thumb, for 8-bit or RGB images it should be at least as large as the radius of the largest object in the image that is not part of the background. Larger values will also work unless the background of the image is too uneven.

How do you subtract a background in Imagej?

Background can be subtracted using the “Subtract Background” tool: Process – Subtract background… The “Rolling Ball Radius” should be larger than a typical object in the image. Test using the “preview” option, start with 100 pixels. Save the background-subtracted image.

When to use the rolling ball image algorithm?

Sternberg, Stanley R. “Biomedical image processing.” Computer 1 (1983): 22-34. DOI:10.1109/MC.1983.1654163 In scikit-image, the rolling ball algorithm assumes that your background has low intensity (black), whereas the features have high intensity (white).

How does rolling ball image background subtraction work?

I am currently doing particle detection on some images and I wanted to do an Image Background Subtraction similar to what is available on ImageJ so as to even out the background tone. ImageJ uses a Rolling Ball algorithm which I believe is a type of Top-hat transform using a ball as a structuring element.

Which is the background of a rolling ball?

A ball of given radius is rolled over the bottom side of this surface; the hull of the volume reachable by the ball is the background. http://rsbweb.nih.gov/ij/developer/source/ij/plugin/filter/BackgroundSubtracter.java.html This algorithms are perfect for microscope images, to distinguish particles from background.

Is there an OpenCV implementation of ” rolling ball ” background subtraction algorithm?

Is there an OpenCV (android) implementation of “rolling ball” background subtraction algorithm found in ImageJ: Process->Subtract Background? OpenCV has a BackgroundSubtractorMOG class, but it is used for video streams not single, independent images.