Pixel Sharp Media

The word pixel is a contraction of the first two syllables of the English pic ture el ement and represents a single point (named dot ) on the screen of the computer or a digital image . Many points together give a picture. Everything on the screen is composed of a plurality of pixels.

The number of pixels on a screen (or off) determines the resolution of the screen. Screens of personal computers consist of eg 320 x 240 pixels or 640 x 480 pixels. Most current displays have a resolution of 800 × 600 pixels, 1040 x 800 pixels or more. The more pixels are available, the sharper the picture.

Pixel Dimensions

Pixels have no specific size. A display with a large area could contain as many pixels as a screen with a much smaller area. The image on the smaller screen will therefore look better because on the big screen, our eye can perceive individual pixels. This difference is particularly evident when an almost horizontal line is shown: on the larger screen the cascade effect of the line will be easily visible. A measure of the number of pixels is DPI (dots per inch). A higher DPI value gives more detail on the same surface. Typical values for DPI computer screens are between 50 and 100 DPI. Printers often have higher DPI values based photo printers often advertise huge values.

A pixel does not need to be square: it can prevent lower horizontal resolution than vertical or vice versa, for example in a widescreen. There are also horizontal and vertical dpi numbers. The ratio width: height is often called pixel ratio.

Digital pictures are made up of pixels and may also differ in size. The number of pixels per inch (PPI) called the resolution of the digital image. The higher the resolution the better the detail.

Color Information

Each pixel has a color. This color is often described with one or more bits (a "bit" is an abbreviation for "binary digit"). The number of bits per pixel determines how many colors a pixel can display. A two-bit pixel can display four colors, an 8-bit pixel displays 256 colors. In general, each additional bit doubles the number of colors available. What different colors a pixel can display depends not only on the number of bits available, but the color coding used. It can be agreed that each primary color will be a number of bits (RGB) or any unique combination of bits refers to a certain color on a palette. The latter system is used in GIF plates, which can use up to 256 colors.

The higher the image resolution and the greater the number of bits per pixel, the more computer memory needed for all information on the screen process. In the simplest view (1 pixel = 1 bit) can only be one pixel 'on' or 'off'.