HTML and Code design insider tricks

Digital Imaging

An image has to be digitised for a computer to understand it and therefore any image on a computer is digital.   Manipulating these images (view, edit etc) is Digital Imaging.

Image Resolution

The total number of pixels in an image.  The more pixels the better the image.  This is expressed in dots per inch (dpi) and therefore a printer with 600 dpi resolution will produce an image with 600 dots in a line within each inch.  The more dots the  better the print quality.

A computer monitor uses the smae way to discribe its quality of display.  A 640 x 480 will display an image with 640 pixels on 480 rows.   Higher quality display resolution could be 800 x 600 or 1024 x 768 or 1280 x 1024

Colour depth

This refers to the maximum nuber of colours that an image contains and is dictated by the resolution of the image.   Usually expressed in terms of  8 bit or 16 bit or 32 bit.

8 bit images contain upto 256 diferent colours

16 bit images contain upto 65,536 diferent colours

32 bit images contain upto 16 milion different colours

Hence the colour depth is sometimes is refered to as the bit depth as it can be seen theay are directly related.