Multimedia Types - JPEG

“Multimedia means that computer information can be represented through audio, video, and animation in addition to traditional media (i.e., text, graphics/drawings, images).” (Dave Marshall, 2004)

Multimedia applications can be found in different areas such as advertisements, art, education and many others.

Image is one of the rapidly developed multimedia technologies; usually it simplifies complex information as it conveys information quicker. Images compression is basically about reducing the number of pixels or grey levels of a source image.

JPEG, which stands for “Joint Photographic Experts Group” JPEG, is a Lossy compression scheme, which discards useless data during encoding. An image-compressed with JPEG is identical to the original image when uncompressed.

“JPEG is capable of producing very high-quality compressed images that are still far smaller than the original uncompressed data”. Web user for faster transmission mostly uses JPEG Image compression across network.

As well JPEG is one of the most widely used image format for digital cameras, the digital file size which the camera produces depends on the pixel count, each pixel generates 3 bytes, for example 10 MP camera generates 30 MB image file. Digital files can be compressed with JPEG without degrading in quality; in JPEG we can reduce the file size by the factor of 10, and still get a very high quality image.

However, JPEG is not the best compression method to compress images with large area of single color. As well if fast decompression is required then hardware-based JPEG solution is better than software based which is slow.

References:

Atkins, Bob (2003) Digital Cameras – A Beginner’s Guide [Online], Available from:

http://photo.net/equipment/digital/basics/

Marshall, Dave (2004) Introduction to Multimedia [Online], Available from: http://www.cs.cf.ac.uk/Dave/Multimedia/node10.html#SECTION01221000000000000000

Monash University (2006) Images and multimedia [Online] Available from:

http://www.monash.edu.au/staff/web/content/images.html

Murray, James D., Van Ryper, William (1996) Encyclopedia of Graphics File Formats, 2nd ed. 103 Morris street, Suite A, Sebastopol, CA 95472: O'Reilly & Associates Inc.