Compression

What is compression?

Compression is the process of reducing the size of the data in order to save space or transmission time. For data transmission, compression can be performed on just the data content or on the entire transmission unit.

Graphic image file formats are usually designed to compress information as much as possible (these can tend to become very large files).
Graphic image compression can be either lossy or lossless.


Effects of compression?

The images' file size will become smaller (some programmes will ask the specific size you are wanting to compress your image to).

The quallity of the image may be reduced.

Smaller files can be tranferred faster. This is beneficial with web design as it would take less time to upload the image and then display it.

Lossy
This type of compression reduces the size of the image by removing some data from it. Some colour data is usually removed in this process.
This type of compression reduces the quality of the image.
Some of the inofrmation is permanently lost in this process.

Lossless
This type of compression reduces the size of the image by changing the way in which the data is stored. Therefor this type of compression will make no visable changes to your image.



How can digital images be caputred?

Scanner-
Scanners are usually used to capture images from old photographs or documents.
Old photographs are physical prints so the scanner is the best way to capture these images.
In the games industry this type of image capture would be best suited for capturing concept art.


Digital camera-
Digital cameras are one of the main ways of capturing images. It is a very simple process of snapping the picture, connecting to pc, and transfering.
The image size can be changed on the camera before the image is captured. The image can be further compressed using compression or editing programmes.
Digital cameras are a good choice to capture detailed texture graphics for games.


Graphics Tablets-
Graphics tablets are used to draw images straight onto the computer. This makes the                    process much more realistic to really drawing rather than using a mouse.
Graphics tablets can be used to create a lot of digital art in games, for example the background art could be done this way.
Some concept art may be done this way rather than by hand.