About Picture Formats

There are two basic methods for storing and displaying images on a computer: raster or vector picture formats. The type of picture format to use ultimately depends on the purpose of the image. Will the image be used for the web or in print?

Features

A raster image format is composed of a series of dots, or pixels. Each pixel is formed by ones and zeros, or bits. The amount of bits that a computer uses to create each pixel displays the color depth of an image. A raster image can be composed of a minimum of one bit to a maximum of 256 bits. Keep in mind that the greater the number of bits, the greater the file size. Enlarging a raster image will result in distorted and jagged pictures, known as pixelation.

Types

Types of raster picture format include GIF, JPEG, Bitmap, MAC, PSP and TIFFs. The most common of raster formats are GIFs and JPEGs. Raster picture formats can be created and edited in programs, such as PhotoShop or PaintShopPro.

Function

GIFs and JPEGS have been most popularized by the their use on the web. For simple, transparent or simple animated images to be used for a website, GIFs would be an ideal choice. For photographs placed on a web, opt for JPEGs.

Features

On the other hand, a vector image, made for a specific software program, is more than a set of colored dots. They are vectors of data stored in mathematical formats that can create any number of shapes that can be edited without loss of quality. Vector images are versatile and are used in the context of creating two-dimensional computer graphics.

Types

Examples of Vector picture formats include: SVGs, SWFs, CDR and EMFs. Vector picture formats are created in vector graphics drawing software programs, or even within everyday Office tools.

Function

Shapes and lines created in Word and charts created in Excel are all vector images that are commonly used. Drawing programs, such as Flash, Illustrator or FreeHand create picture formats that can be used for a number of purposes, since they can be manipulated and scaled.

Considerations

It is fairly simple to convert a vector image to a raster image, but converting a raster image to a vector image will result in loss of quality. This is an important factor to consider if you will be printing an image for a color brochure or creating an image for a billboard. Before creating or buying any type of picture format, be sure to understand the ways you will be using the image. Doing so can save you a lot of time and money in the future.