Page 8 - Computer Graphics

7

Image Representation in Computer Graphics

Image Representation: In computer science, we can represent an image in various
forms. Most of the time, it refers to the way that brings information, such as color
is coded digitally, and how the image is stored, i.e., how an image file is
structured.

Several open standards were recommended to create, manipulate, store, and

exchange digital images. The rules described the format of image files, the
algorithms of image encoding, the form of additional information often named as
metadata.

A digital image is the composition of individual pixels or picture elements. The
pixels are arranged in the form of row and column to form a picture area. The
number of pixels in an image is a function of the size of the image and number of
pixels per unit length (e.g., inch) in horizontal as well as vertical direction.

Image Processing

It is a method to implement some operations on an image. It is also used to get an
enhanced image or to access some useful information from an image. It is a type
of processing in which the input is an image, and output may be the image or

characteristics/features correlated with that image.

For example– photographs, frames of video.

Most image processing techniques consider the image as a two-dimensional and
applying standard signal-processing technique on it.

Pixel: “Pixel is the smallest unit of a picture displayed on the computer screen.”

A pixel includes its own: -
 Intensity
 Name or Address

The size of the image is defined as the total number of pixels in the horizontal
direction times the total number of pixels in the vertical direction (512 x 512,640
x 480, or 1024 x 768).

The ratio of an image’s width to its height, we can measure it in unit length or
number of pixels, is known as the aspect ratio of the image.