Digital Graphics File Formats

Emily Pinder

Raster Graphics

• Give a definition of Raster Graphics

• Raster graphics are bitmaps which are made up of pixels which create an image on a computer. Each pixel records its own colour which has a fixed resolution size. The more pixels an image has the more detail the image will contain.

Vector Graphics

• Give a definition of Vector Graphics

• Vector graphics are images that are made up of paths and strokes. These paths are created by the computer to put the image together. Vectors are like a mathematical calculation which create the image.

Raster Graphics

JPEGStands For Joint Photographic Experts Group.

Used For/Example JEPG is a photograph and web format that most images are saved as.

Advantage The file size of JPEG can be highly compressed to make the file small and allow room for more images. A lot of different websites, cameras and computers around the world use the JPEG format which means the files are highly assessable.

Disadvantage Due to the high level of compression and recompression every time you edit and close the file, the file loses quality and overtime the image will degrade.

TIFFStands For Tagged Image File Format

Used For/Example Used for desktop publishing such as for magazines and graphic designs.

Advantage A TIFF file can have multiple pages in a single document. Tiff files also have the option of lossless compression. This means you do not lose any quality of the file due to compression.

Disadvantage TIFF files are specialist and many computers and programs will not open them. The files sizes are huge and they take a while to download and open.

GIFStands For Graphics Interchange Format

Used For/Example GIFs are used to create short digital animations using a series of images, played in a loop. They are often found on the internet.

Advantage GIFs are small files and are not very hard to make. They are only a few seconds long and are played on a constant loop.

Disadvantage GIF files are very small so the quality of the images are bad. They are not hard to make however you need specialist software to make them.

BMPStands For Bitmap Image File

Used For/Example Similar to a TIFF and JPEG file.

Advantage No loss in compression when the file is opened, edited and closed.

Disadvantage Due to this lossless compression this file size is very large.

Vector Graphics

PSDStands For Photoshop document

Used For/Example Used for imaged manipulation. For example editing magazine covers.

Advantage A photoshop document saves each stage of editing in a layer so you can still edit the image after saving. It also saves the page format and other information. This document also supports transparency.

Disadvantage PSD files cannot be opened with a web browser. Due to the large files sizes, the files are difficult to email and transfer.

AIStands For Adobe Illustrator Art.

Used For/Example Used to create graphics to represent companies.

Advantage Often used in logo creation and can be scaled bigger or smaller as the vectors have no loss in definition and do not pixelate.

Disadvantage For these files you need specific Adobe software to open and edit the file. The files are also often very large.

FLAStands For Flash File

Used For/Example Flash files are used to create animations and games.

Advantage This program can produce high quality files with a small file size. The files can also include sound and video.

Disadvantage Flash files are very large and can only be be seen when Flash Player is installed. They files can also take longer to load on webpages.

WMFStands For Windows metafile.

Used For/Example Windows metafiles are used for logos and are similar to AL files.

Advantage This program can be scaled larger or small as vectors do not lose any definition. WMF files can contain both vector and bitmap components.

Disadvantage Few programs support this file and the program can be hard to use. There is a lack of editing features with the software.

File Format Capture and Optimising

CompressionDefinition Lossy compression is the way in

which the size of a file is reduced. This is done by reducing the amount of information that is saved to the file.

Advantage Compression can drastically reduce the size of a file allow room for more files.

Disadvantage Due to the compression, images become more pixelated as they have less detail and less squares of colour.

Image CaptureMethod Scanner

How is it used for image capture of graphics

A scanner can digitise physical images such as sketches and mixed media by recreating the image using pixels.

Method Camera

How is it used for image capture of graphics

A camera is used for taking pictures of graphics which can then be edited.

Method Graphics Tablet

How is it used for image capture of graphics

When using a tablet you can use the mouse like a pen giving you more control of the image.

OptimisingWhy would you optimise? Optimising images is good for

reducing the file size and download speed allowing easy viewing on the internet.

How can you optimise? Images can be optimised from the internet by changing image size in photoshop. You can also reduce bit depth which reduces the amount of colour in an image and reduce the resolution of the pixels.

Advantage to optimising An advantage to optimising is reducing the file size which makes the file a lot more assessable.

Disadvantage to optimising A disadvantage to optimising is the loss of quality of the image as the bit depth will show less amounts of colour and the pixels are reduced, reducing the resolution of the image.