Images stored as a series of tiny dots called pixels. Each pixel is assigned a colour, and when they are viewed together they form a picture
Used for digital photographs
Vector Image Format
Images made up of mathematical formulas consisting of lines and curves. With the exception of flash (vector graphics program) most browsers do not support vector graphics on the web
Used for Text and simple logos
Commonly used on web pages, graphics interchange format (GIF) files are unlike many other popular image formats in that they only support up to 8 bits of colour depth (256 colours). However, since the GIF format uses lossless compression, it does not noticeably degrade the original image when resized.
Used in simple web graphics such as navigational buttons and headers
Joint Photographic Experts Group (JPEG) files provide full 24-bit colour but use lossy compression. While most users won’t see much of a difference between a moderately compressed JPEG and the original image, a heavily compressed JPEG will appear blurry and make individual pixels noticabe.
Used in photographs, especially in web sites
Remain as separate files from the destination file, can be updated independently
Stored as part of the destination file, cannot be updated
The set of colours included in an image. Defined as a designated subset of the total range of colours supported by a computer graphics system. Each colour in the palette is assigned a number, and for each pixel, one of the these numbers is stored. This number determines the colour of the pixel.
Any method of data compression that guarantees the original data can be reconstructed exactly, bit-for-bit
Not usually used by JPEG files which use lossy compression
Problems with .bmp format
Reducing the size of a bitmap file distorts the original image because pixels are removed to reduce the overall image size. Increasing the size of a bitmap has the effect of increasing individual pixels, making lines ad shapes appear jagged.
There are large memory requirements for this type of graphic as each pixel requires 1-3 bytes of memory
Flickr is an online program that allows people to store, sort, search and share photos. Someone may use this so they can share photos with their friends or so that they can look at their friend’s photos.
It is predominantly a recreational tool but does allow the viewing and transfer of photos which could have an academic use