Digital Graphics File Formats

Unit 54 Digital Graphics for PrintLearning Outcome 1

Raster GraphicsRaster Graphics are one of the main types of

digital graphics. They are made up of Bitmaps (or pixels) which record the colour information of that section of the image. Bitmapped images have a set resolution meaning that changing the size of the image results in it becoming distorted (or pixelated).

Vector Graphics Vector Graphics are another main type of digital

graphics. They are made up of Vectors (or paths/strokes) which are defined by the start point and end point, with curves and angles between them. Vectors can be resized infinite times and pixilation won’t occur. This means that Vector Graphics are good for commercial uses such as company logos that need to be in many different formats/sizes.

Distinction between Raster and Vector GraphicsRaster graphics will become pixilated after

resizing an image, whereas, Vector graphics offer lossless compression – retaining all of the original data, even after resizing.

Here is a diagram to help explain the fundamental difference between the two:

Raster Graphics

JPEGStands For Joint Photographic Expert

GroupUsed For/Example JPEGs are primarily used for

photographs and on websites. They are used widely on the internet.

Advantage • Small file size.• Good for use on websites where

data usage is important.• Widely compatible with most

mobile phones, tablets, computers, cameras etc.

Disadvantage • Sacrifice image quality for file size meaning that they aren’t always optimal visually.

• Because JPEG is a Raster Graphic, changing the size of the JPEG will result in it becoming pixilated.

TIFFStands For Tagged Image File Format

Used For/Example Newspapers/magazines/publishing. Useful for graphic designers.

Advantage • Lossless compression means that the file doesn’t lose composition.

• TIFF enables multipage documents in a single file, which is extremely useful for magazine covers and publishing.

Disadvantage • Large file size compared to other raster graphic formats – could be inconvenient.

• Isn’t available on as many platforms as JPEG, for example. May required specialised software to be able to view.

GIFStands For Graphics Interchange Format

Used For/Example Mainly used for low file size animation on the internet.

Advantage • GIFs are essential a series of images played quickly to create the illusion of movement. This means that they have a low file size in comparison to other video formats. GIFs are a good alternative to larger video formats.

• Offers lossless compression meaning that this format will not lose resolution.

Disadvantage • Due to GIFs being very compressed, their quality can be poor and pixilated.

BMPStands For Bitmap Image File

Used For/Example Common format in image processing programs.

Advantage • Lossless compression means that the file doesn’t lose composition.

• Optimised for Windows operating systems.

Disadvantage • BMP has a large file size meaning that it could be inconvenient to upload to the internet.

Vector Graphics

PSDStands For Photoshop Document

Used For/Example PSDs are used almost exclusively for Image Manipulation in Adobe’s Photoshop.

Advantage • Specialised – designed for a particular purpose and are good at what they do.

• Saves all of the layer information and page formatting in a single document.

• Lossless compression – No loss in definition. PSDs can be perfectly reconstructed.

Disadvantage • File sizes can become extremely large which means that they have to be converted if needed to be viewed effectively as an image.

• Not necessarily compatible with some platforms/devices/software.

AIStands For Adobe Illustrator Art

Used For/Example Used for creation of logos/designs in specifically in Adobe’s Illustrator.

Advantage • One of the main features of AI is that they are vectors and so have lossless compression. They can be stretched, resized, uploaded, downloaded and changed in any way, but will not lose definition.

Disadvantage • Can create some massive file sizes unless the image is rasterised.

• Designed for use in a specific program and so is only compatible with particular programs.

FLAStands For Flash File

Used For/Example Used to create animation and games in Adobe’s Flash systems.

Advantage • Can produce a high quality file with a relatively small file size.

• Files can also record sound and video which is something not many other image formats have.

• Widely readable/used on the internet and with most software.

Disadvantage • Created for specific use in Adobe programs, so there may be platforms/software that can’t read FLA.

WMFStands For Windows Metafile

Used For/Example An image format originally created for Microsoft Windows in 1990. Can be used to create designs and logos.

Advantage • WMF have lossless compression meaning that they do not lose definition unless they are rasterised.

Disadvantage • Have become largely irrelevant and replaced by more efficient file formats (such as AI.)

• As this format was designed in a particular operating system, it might not be compatible with systems like Apple’s Mac or Linux.

File Format Capture and

Optimising

CompressionDefinition Compression is reducing the amount

of bits in an image to reduce the file size. If a file has lossless compression, then the image will never lose definition. But if a file has lossy compression, then it has been changed by reducing the information in each pixel to make the file size smaller.

Advantage The primary advantage of using compression in images is that the file is carrying less information and therefore, the file size is reduced substantially. It is sacrificed for a lesser quality of the image in general as all of the bits will have less colour information.

Disadvantage The disadvantage is that the quality and clearness of the image is largely affected by compression, meaning that the image will appear blurry and distorted instead of clear and in it’s original quality.

Image CaptureMethod Scanner

How is it used for image capture of graphics

Scanners can be used to process physical documents and turn them into digital copies so that they can be sent/used online. They are useful in professional office working environments. Method Camera

How is it used for image capture of graphics

Cameras are commonly used to create photographs of surroundings and to record data via an image. They create a digital copy of this information so that it can be imported to a computer and used online. Method Graphics Tablet

How is it used for image capture of graphics

Graphics tablets have the primary function to manipulate images on a mobile device – essentially a portable version of Adobe’s Photoshop.

OptimisingWhy would you optimise? You would optimise an image if

you were uploading it to the internet as if an image is not optimised, it might take a long time to load that web page.

How can you optimise? One way to optimising an image is changing the size and dimensions of it. This is a basic function in any photograph manipulation software. In Photoshop, it can be done by going into Image>Image size.

Advantage to optimising • The file size is smaller making it easier and quicker to view on the internet.

Disadvantage to optimising • The file is smaller, meaning that it’s not in it’s original format.

• Some forms of optimising can make the file lose quality.

Storage

File SizeWhat could affect a Working Scale (Photoshop) document

file size?

The Working Scale will affect the dimensions of the image, meaning that the larger the width and height, the larger the file size is going to be. This is because as the width and height are increased, so is the amount of pixels in an image.

How could you reduce the file size of a Working Scale

document without affecting quality?

To reduce a file size without affecting the documents quality, you would have to give the image a smaller resolution by going into Image > Image Size in Photoshop.

What is an advantage of scaling up images before

exporting?

Making an image larger before it is exported is good because this means the picture will last longer (damaged through saves and uploads.)

What is a disadvantage of scaling up images before

exporting?

A disadvantage of this is that by scaling up the image, you could cause pixilation and reduce the quality of the image.

File Naming ConventionsWhat naming conventions

could you use when creating your video game assets?

To keep organised, I will have a structure in my files to make them easier to find. They will be named exactly what they are: for example, if there is a rotoscope of an elephant, it will be name elephant1.psd (or .jpeg or whichever format it is in. If there is an updated version of this file, it will be name elephant2.psd and so on.

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

It’s good to be organised so that you don’t lose any work as what I will be working on are large files which I will spend many hours on.

Asset ManagementWhy would you use folders when storing your assets?

Folders are a good idea because this keeps your work in order and organised. This avoids having a messy storage device which has lots of randomly named files and many different projects.

What folders would you create and what would you save

within them

• I will have all of my work saved into a folder called “Print Based Media” and then that folder sectioned into sub-catergories such as “Rotoscoping” or “Lecture Powerpoints”. This will enable me to know where everything is and keep a clean, pristine storage system.

References1. Various. (2015). Vector graphics. Available: https://en.wikipedia.org/wiki/Vector_graphics. Last accessed 24th

November 2015.

2. Various. (2015). Raster graphics. Available: https://en.wikipedia.org/wiki/Raster_graphics. Last accessed 24th November 2015.

3. Various. (2015). JPEG. Available: https://en.wikipedia.org/wiki/JPEG. Last accessed 26th November 2015.

4. Various. (2015). Tagged Image File Format. Available: https://en.wikipedia.org/wiki/Tagged_Image_File_Format. Last accessed 26th November 2015.

5. Various. (2015). GIF. Available: https://en.wikipedia.org/wiki/GIF. Last accessed 26th November 2015.

6. Various. (2015). BMP file format. Available: https://en.wikipedia.org/wiki/BMP_file_format. Last accessed 26th November 2015.

7. Various. (2015). Adobe Photoshop. Available: https://en.wikipedia.org/wiki/Adobe_Photoshop#File_format. Last accessed 27th November 2015.

8. Various. (2015). Adobe Illustrator Artwork. Available: https://en.wikipedia.org/wiki/Adobe_Illustrator_Artwork. Last accessed 27th November 2015.

9. Unknown. (2015). FLA file extension. Available: http://www.file-extensions.org/fla-file-extension. Last accessed 27th November 2015.

10. Various. (2015). Windows Metafile. Available: https://en.wikipedia.org/wiki/Windows_Metafile. Last accessed 27th November 2015.