Graphics And Image Files[1]

Graphics and Image Files Vlad Botchkarev Saadat Ahmed Emma Boothman Dave Hughes

Vectors and Bitmap (Raster) Images

Vector images Are defined mathematically by the computer Can be modified Easily scalable Less memory required

Bitmap images Rectangular grid of pixels with each pixel holding

a specific colour value Suitable for photos

GIF and JPEG Images GIF Suited for simple images such as

graphics or logos

JPEG Suited for photos and images with

smooth variation of tone and colour Relatively small file size Quality decreases when repeatedly

edited and saved

Embedded and Linked Graphics Embedded files

Permanently linked to document

Independent of original source Stored as part of the file and

not externally

Linked files Dependent on original source Change if source document

changes (e.g. Microsoft Excel spreadsheet)

Not stored as part of document; need to be present with document

Default action after copy-paste is embedded. Source: Microsoft Office Online Help

http://previews0.coolclips.com/01/tf05038/NVTech_busi0407.jpg

What is a Colour Palette? Collection of colours used by the

image Different colour ranges for different

uses

Personal photography, advanced editing High-resolution, 24 bit (16 million

colours) Uses large palette

Web-based imaging Lower-resolution, 8 bit (156

colours) Small palette

Not all computer monitors designed with advanced colour range

Faster loading speeds via slow connections

http://www1.istockphoto.com/file_thumbview_approve/720581/2/istockphoto_720581_painter_s_palette.jpg

Source: PaintshopPro Help

What is Lossless Compression? Do JPEG files normally use this?

Lossless compression is the compression of a file without a loss of quality

Jpeg files do not use lossless compression

The image is an exact copy whilst taking up less disk space

Taken from: http://en.wikipedia.org/wiki/Lossless_compression

What the FBS skills wiki says about png files

Png – portable network graphics It is a bitmapped image format that

employs lossless compression It was created to improve on gif

format, and overcomes many problems that are associated with gif and jpg files

It does not, however, support animationsTaken from: FBS skills wiki

Why .bmp format images are bad and why should you avoid using them?

.bmp images cannot be compressed, therefore will have a large file size.

They are not capable of storing animation.

They are not supported by web browsers.

Taken from:http://support.microsoft.com/kb/320314

and http://www.fortunecity.com/skyscraper/windows/364/bmpffrmt.html

What is Flickr?

It is a worldwide photo sharing website.

Used for communal purposes and used by bloggers.

Can also be used in group work to allow easy access for all members of a group to access the same material to use it in one shared document. Taken from: http://en.wikipedia.org/wiki/Flickr