JNTU B.Tech IV COMPUTER VISION Previous Question Paper (September - 2020 - R16)

Erosion is a fundamental morphological operation that shrinks or thins objects in a binary image. It is defined by the set of all points where the structuring element fits entirely within the foreground of the image. Mathematically, for an image A and a structuring element B, erosion is denoted as A ⊖ B. The operation is computed by sliding the structuring element over the image; a pixel at the center of the structuring element is set to 1 only if all corresponding pixels in the image under the structuring element are 1. Otherwise, the pixel is set to 0. This process effectively removes small noise components, breaks thin connections between objects, and separates touching objects.

Dilation is a morphological operation that expands or thickens objects in a binary image. It is defined by the set of all points where the structuring element intersects with the foreground of the image. Mathematically, for an image A and a structuring element B, dilation is denoted as A ⊕ B. The operation is computed by sliding the structuring element over the image; a pixel at the center of the structuring element is set to 1 if at least one pixel in the image under the structuring element is 1. This process effectively fills in small holes or gaps within objects, bridges small breaks in contours, and enlarges the boundaries of foreground regions. Dilation is the dual of erosion, often used in preprocessing steps to connect fragmented parts of an object before further analysis.