Digital Graphics File FormatsThomas Williams

Raster Graphics

A Raster graphic is made up of bitmaps. Bitmaps are made up of pixels, each pixel has a specific colour for that area of the image. Images made from bitmaps have a pre set resolution so when resizing an image it can develop some distortion (pixilation) in the image. The images taken by modern cameras are raster graphics, so when a camera states it’s a 10 megapixel camera this means the final image will be made of 10,000,000 pixels.

Vector Graphics

Vector graphics are made up of vectors/paths, vectors have a defined start and end to them, these will have angles, curves and points between them. These vectors can be made into any shape possible. When vectors are resized there is no pixilation or deterioration in the image. Vector graphic are perfect for images that need to be used on multiple times at many different sizes, such as a company logo that will be small on a pen but large on the side of a vehicle.

Raster Graphics

JPEGStands For Joint Photographic Experts Group

Used For/Example Images on the Internet and photographs

Advantage One of the most common file types when it comes to picture files, this means there are lots of programs that can read JPEG images. They can also be read on all modern mobile phones.

Disadvantage JPEG images can lose there quality over time if they are compressed and recompressed with multiple edits, that is why it is best to only save a finished image in a JPEG.

TIFFStands For Tagged Image File Format

Used For/Example Desktop publishing, TIFF’s are very popular with graphic designers.

Advantage A single TIFF file can have a multi page document saved to it. TIFF’s also have the ability to be saved with lossless compression which means they do not lose any quality when they are compressed.

Disadvantage Generally quite a large image size, so larger storage devices will need to be used. Majority of websites do not support TIFF files and the ones that do have a very slow upload speed.

GIFStands For Graphics Interchange Format

Used For/Example Used to create small animations often found on the internet.

Advantage They use a relatively small file size so there able to be uploaded to the internet quickly and still retain there quality. GIF’s also support a transparent background, this means they can be placed on top of any background.

Disadvantage There are only 256 colours that make up a GIF file so they can appear pixelated at times. Another disadvantage is that once the GIF has been animated it can not be edited anymore meaning if there was a mistake you will have to go back and start again.

BMPStands For Bitmap

Used For/Example Similar uses as a TIFF and JPEG file, so they would be used for things like images on the Internet, photographs and desktop publishing.

Advantage Doesn’t degrade over time like a JPEG can with multiple edits and saves. Very versatile file format because it is supported on nearly all devices and a large range of programs.

Disadvantage Can be a very large file size, compression can be achieved but the file must but uncompressed before it can be used which can slow down the reading process. Can not be scaled very well so normally must be used at the resolution it is saved in.

Vector Graphics

PSDStands For Photoshop Document

Used For/Example Image manipulation

Advantage A PSD file remember all layers separately and any individual formatting you have done to each layer.If desired it can support a transparent background but this can still only be used in Photoshop.

Disadvantage A PSD tends to have a very large file size, especially files that have many layers with lots of adjustments to each layer.Can only be read by adobes program Photoshop so the file needs to be converted to a more widely used file type like JPEG.

AIStands For Adobe Illustrator Art

Used For/Example Creating company logos

Advantage Can be scaled up or down to any size as it will not lose any of its definition.Can be opened on a multitude of programs such as Adobe After Effects, CorelDRAW, DrawPlus, just name a few.Most advanced vector format widely available to the mass market.

Disadvantage Even though it is the most advanced vector file it is not a standard format, the standard format for vector graphics would be PSD. Newer versions may have compatibility issues with older programs.

FLAStands For Flash File

Used For/Example Creating animations and games

Advantage Can be used to create very high quality documents with a relatively small file size.Ability to use sound and video to enhance project.

Disadvantage Unable to be uploaded to the internet so it has to be exported as a SWF (ShockWave Flash) file first.

WMFStands For Windows Metafile

Used For/Example WMF files have a similar use as AI files they are also used for clipart images.

Advantage Can be scaled up and down with out any loss in quality.Unlike some vector file types, a WMF file can contain both vector and bitmap parts.

Disadvantage Work best on windows devices as it was initially designed for windows.

File Format Capture and Optimising

CompressionDefinition Compression is the processes of reducing a

files size by limiting the amount of coloured squares that are saved.

Advantage An advantage to compressing a file is that it is easier to upload to the internet, email to somebody or view on the internet.

Disadvantage The higher the compression the more chance pixilation can occur.

Image CaptureMethod Scanner

How is it used for image capture of graphics

It is used to capture physical images, these could be drawings, printed photographs, pages from magazines, etc.

Method CameraHow is it used for image capture of

graphicsA camera is used to take photographs of the world around the photographer, most commonly taken in a digital format (JPEG file)

Method Graphics TabletHow is it used for image capture of

graphicsThis is used for more precise manipulation of programs like Photoshop to create more accurate artwork.

OptimisingWhy would you optimise? You would optimise an image to make

viewing on the internet easier.

How can you optimise? You can optimise an image on Photoshop by changing the image size to no more then 500 pixels wide.

Advantage to optimising An advantage to optimising an image is to increase the download speed of the file.

Disadvantage to optimising A disadvantage to optimising an image is that you end up with a relatively small image that if it is a file that uses bitmaps it may not scale very well.

Storage

File SizeWhat could affect a Working Scale (Photoshop) document file size?

There are a few things that can effect a PSD file size, these include the size of the image, the number of layers used, also the number of images used and there original file size.

How could you reduce the file size of a Working Scale document without

affecting quality?

To reduce the file size you could merge certain layers together, you could also save it in different formats that retain the quality of the image but have very small file sizes like a JPEG.

What is an advantage of scaling up images before exporting?

Pixilation is more likely to occur when scaling an exported image up then scaling it down.

What is a disadvantage of scaling up images before exporting?

By scaling a image up before exporting will increase the file size.

File Naming ConventionsWhat naming conventions could you use when creating your video game assets?

• Specific names• Numbering• Descriptions• Dictating the part of the video game it

is for.

Why is it a good idea to accurately name your assets?

Is to use specific names that will accurately depict where that certain asset should belong in the final project.

Asset ManagementWhy would you use folders when storing

your assets?You would use folders to split up assets that could have similar names but are for different parts of the project.

What folders would you create and what would you save within them

I would create folders for each character of the project, within each folder would contain the different assets that make up the character, such as left arm, right arm and other body parts. These assets would have the same name as assets for other characters.