Digital Graphics File Formats

Hannah Woollaston

Raster Graphics• Raster graphics are made up of Bitmaps, these are made up of pixels, then the pixels record

the data and information that makes up the image. Because raster graphic images are made up of bitmaps, they have a fixed resolution, unfortunately this means that resizing a bitmapped image can result in distortion and pixilation, this can make an image or graphic look un-professional.

• More information on Bitmaps and Megapixels…Cameras often mention megapixels, this is telling you how many million pixels or ‘bits’ the image is being separated into, the more pixels the better because this makes the image clearer and less bitty, the clearer the image, the better. Megapixels and bitmaps means the image is split into millions of the little squares, which each, in turn records the information of what size/colour etc. each part of the image should be, as an example, when you use an image from the internet it can sometimes become pixilated because it has been compressed when downloaded to less megapixels to make it easy to view/ use/ download.

Vector Graphics

• Vector graphics are made up of vectors, which can also be known as strokes and paths, are defined by a start and end points which contain curves, angles and points between each point. From the information contained within these vectors, the paths within the graphic can become any shape it needs to, for example, a square, a curvy shape, a triangle or even just a line. Vectors can be scaled both small and big, this is because vectors loose no detail or definition when scaled to different sizes, this enables vector graphics to be very flexible and a popular choice for business’ as vector graphics can be made small on leaflets or big on a posters.

Raster Graphics

JPEGStands For Joint Photographic Experts Group.

Used For/Example JPEGS are one of the most common choices for photographers as most cameras are set to use this format as default. It can also be found on web formats, people come into contact with JPEG files quite often as photos on Facebook are saved as them and photos on phones are saved as JPEGS to.

Advantage -JPEGS are universally used so a file saved as a JPEG can be accessible to a lot of people, making it a popular format for people to share things on. -Because it is compressed, it is easy to open online, even if the internet connection is slow.

Disadvantage -JPEGS loose quality each time you open and edit them as each time they are compressed and recompressed.-JPEGS images are not the best quality as they are made up of bitmaps and pixels so they only look good in a certain resolution

TIFFStands For Tagged Image File Format

Used For/Example Tiff files are popular with graphic designers as its used for desktop publishing .

Advantage -Have the option to keep the quality of the image, even when opening, closing and editing the file, this is called ‘Lossless compression’ -It can save multiple paged documents in a single file which, for example, is good for people working on designing magazines.

Disadvantage -Tiff files are not yet universally used and are normally only used within the field of graphic design which makes it difficult to share the file. -Tiff files get bigger each time as they don’t compress, this is an example of the constant battle between quality/file size. This also means that the files are difficult to share via email so a memory stick would need to be used.

GIFStands For Graphic Interchange Format

Used For/Example They are used for short digital animations, maybe to make a document more interesting and engaging, they are just a set of often JPEG images that are played on loop to make it look like a video.

Advantage - Easy to use and find.- Good for basic newsletters and un-

professional documents

Disadvantage -Often poor quality and can be jumpy when moving from image to image in the loop.

BMPStands For Bitmap Image File

Used For/Example Bitmap images files are similar to JPEG and TIFF files, particularly TIFF files because it grows in size.

Advantage -BMP files are reasonably universal so can be shared with people quite easily because it accessible to most people. -BMP files also don’t loose quality in compression so they retain the standard they were first created with.

Disadvantage -BMP files are becoming slightly outdated so they are becoming a less popular choice which means it will become difficult for people to share their work on this file type. -big file size because of lossless compression

Vector Graphics

PSDStands For Photoshop Document

Used For/Example Used for editing/creating images, creating fonts etc.

Advantage -lots of tools and techniques available, this helps to make editing the picture easier and makes the final image look more professional.-another advantage would be that it offers the option to save a a PSD file so it remembers the layers of each image and the effects applied to them so you can carry on working on image.

Disadvantage -Only people who have Photoshop can open Photoshop files, this makes it difficult to share work with others, it also means you can only work on PSD files on computer that have photoshop.- PSD files can be quite large, so take up a lot of room on memory sticks etc.

AIStands For Adobe Illustrator Art

Used For/Example Adobe illustrator art is commonly used by businesses for designing logos and posters etc.

Advantage - Designs can be made big or small without loosing quality because they are not made up of bitmaps. (this relates to the example above).

- AI files do not loose quality each time when saved and edited.

Disadvantage - Because AI files do not loose quality the files grow in size each time, so take up a lot of room.

- AI files can only be opened/edited on computers which have Adobe Illustrator art, which makes it difficult to share work.

FLAStands For Flash File

Used For/Example Used to create animations and games.

Advantage - FLA files produce high quality games/files but with a small file size so they don’t take up loads of room.

- You can include sound and video in FLA files, so this helps to make the animation or game more professional.

Disadvantage - Not completely universal yet but they are getting there.

- Can take a while to get use o how to use the program.

WMFStands For Windows Metafile

Used For/Example Used for logos, however they are not use by professionals as it is not the best program to use.

Advantage - Can be scaled big or small as it does not loose quality because it is a vector.

- They are good for making logos because of the point above.

Disadvantage - WMF are not used by professionals this is because it is not the best out there to use, this is because the tools for creating and editing are not as good as other programs.

- Because the files are not compressed they grow in size each time.

File Format Capture and Optimising

CompressionDefinition Compression happens on some file types

so that the files don’t get bigger and bigger and take up too much room, lossy compression is a way information on a particular file is striped out to make the file smaller.

Advantage -by compressing this stops the files from getting bigger each time they are edited and opened, this makes them easier to open/download.-compressing the files can make them pixelated, this can be beneficial because it can stop people from stealing the images.

Disadvantage -lossy compression means the information is striped out of the image, this lowers the quality of the image significantly.

Image CaptureMethod Scanner

How is it used for image capture of graphics

By placing the objects you want to be scanned into the scanner, and scanning them, they then become available to edited/use on the computer.

Method CameraHow is it used for image capture of

graphicsCameras are used to capture imagery by pressing the capture button, the shutter is then exposed and the image is captured, the images can then be uploaded onto a computer by either using a cable or inserting the SD card in to the computer.

Method Graphics TabletHow is it used for image capture of

graphicsImages can be drawn onto a graphics tablet, they normally have a stylus that acts like a pen to draw with.

OptimisingWhy would you optimise? Images are optimised so that they can be

viewed easily online, it is also to ensure they work for the format.

How can you optimise? -SGVO is a good tool or optimising vector images, as it minifies the SVG files (scalable vector graphics).-As for raster files, reducing the number of bytes and RGBA colours this can make the file size smaller.

Advantage to optimising -You can make the images less than 500 pixels wide so they don’t take long to load.-don’t take up as much memory.

Disadvantage to optimising - Can lower the quality of the image.- Easier for people to steal from online

because it makes the images easy to download.