Computer Vision

Digital Image


What is computer vision

Computer vision is a scientific field that tries to get as much information as possible out of images. It develops acquiring, processing and analyzing methods to solve some everyday problems with the help of digital images. Typical tasks of compute vision are:


What is a digital image

A digital image is a binary representation of a two-dimensional image. The term “digital image” usually means raster images (bitmapped images) or vector images.

Raster images

A raster image or bitmap is a matrix data structure which is representing points of colour viewable via monitor or other display mediums. It defines the size and color of all pixel in the display space but it does not need to contain a bit of color-coded information for each pixel. It only needs to tell about a new color while the display scans along the row. Those images are stored in files with different formats (JPEG, GIF, PNG, etc.). Those images are resolution dependent, which means that they can't be scaled up do a higher resolution without loss of quality.

Vector images

A vector image, or vector graphic, is the use of geometrical basics like lines,points, shapes and curves to show pictures on computers. Vector graphics use vectors, to lead trough the control points, which are showing absolute positions on the x and y axes. Those control points decide about the direction the vector has to take. Because of this, vector images can be scaled up to a infinitely size without loosing it`s quality, while pixel-based graphics can`t.

Why is image quality important?

The quality of an image is very important for every website. When people view your website they are making decisions about the level of trust they will have in a few seconds. No matter how decent your website is, if you have images on your website with bad quality, the overall impression of your website can be ruined and level of trust that people will have can be ruined to.

The following image shows the difference between Raster images and Vector images.




Vector Bitmap Example