Digital Graphics File Formats

Samuel Woodhouse

Raster Graphics• Raster Graphics are digitally created images

that are made up of bitmaps. Bitmaps are made up of tiny rectangular pixels inside of a grid which contains both an x and y axis. The pixels are then located on co-ordinates inside this grid. Each pixel contains the colour information for that specific section. Bitmapped images have a fixed resolution, which means that when they are enlarged, they can become very pixelated and distorted. Raster images can be created when something is being scanned.

Vector Graphics• Vector graphics are made up of vectors

(paths/strokes). They have a start poit and an end point, and they use geometric shape formulas in order to represent images and fill in the gaps. They can be used in things such as logo's for companies and they often have a very low file size. They don't lose quality, even after being enlarged, so you could enlarge a vector to whatever size you wanted, whether it be a billboard or a business card.

http://www.brachadesigns.com/design/wp-content/uploads/2015/01/raster_vs_vector.jpg

https://upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Bitmap_VS_SVG.svg/2000px-Bitmap_VS_SVG.svg.png

Raster Graphics

JPEGStands For Joint Photographic experts Group

Used For/Example JPEG’s are used to compress images in order to keep the file size low. They are used in photography to capture a large number of images and on web pages, such as facebook to keep the website running at a fast speed.

Advantage The file size is low, which means more images can be stored and that a website/computer may be able to run faster. They are stored as full colour images and have large compression ratios. The images are usually good quality. JPEG’s are a universal file and can be opened almost anywhere.

Disadvantage JPEG's tend to lose quality over time due to compression and recompression. Each time an image is saved, less pixels will be saved in order to keep the size of the file low. Also, layers can not be saved, as the image is only saved as one full image.

TIFFStands For Tagged Image File Format

Used For/Example TIFF’s can be used for swapping raster graphics (BITMAP images) through different programs. They can be used when scanning certain images. They are commonly used in desktop publishing. Also Adobe Indesign documents are often saved as TIFF’s

Advantage They can be compressed in order toreduce file size. They do this by using specific mathematic algorithms. These mean that no image data gets lost, which is lossless compression.TIFF’s are compatible with both MAC and PC’s. TIFF’s can also save multi page documents.

Disadvantage The size of TIFF files tend to be large, as they can store so much information, therefore a large storage device will be needed to store the images. The majority of websites and online image galleries don’t support TIFF files, they prefer to use file formats such as JPEG.

GIFStands For Graphics Interchange Format

Used For/Example GIF’s are most commonly used to store short, animations that are made up of a series of photos playing on a loop.

Advantage They have a small file size as they are compressed files, this helps them to be easily viewed online. GIF files are also useful as they show movement, which is better than a still image in some cases. They are fairly easy to create.

Disadvantage GIF's are usually in bad quality and they come across as very pixelated. This is partially caused by their colour palette that only contains 256 colours.Once saved, the GIF can’t be edited again.

BMPStands For bitmap image file

Used For/Example They are used when saving image files. They are used for printable images, as they produce high quality products.

Advantage Bitmap Image files are very versatile.They can be used on many different programs on both MAC and PC's. They store colour data for each individual pixel, which results in crisp,high quality graphics.

Disadvantage They are very large files, due to the large amount of image information, so therefore they take up a lot of storage space. Due to their large file size, websites tend to use JPEG's and other file types more often.

Vector Graphics

PSDStands For Photoshop Document

Used For/Example This file format is used primarily for Adobe Photoshop. However it can also be used in other Adobe products, such as After Effects and Premiere. They can be used for image manipulation and magazine covers can be created using these documents.

Advantage The advantages of PSD files are that they retain the layer information. Also they don’t compress the image file, so this means that they keep the same quality of the image. They also contain all of the original image data, such as layers, when they are saved. Therefore they can easily be re-edited later. Images can also be saved without a background.

Disadvantage PSD’s can have a large file size, as the images aren’t compressed. This can take up lots of storage space. Also there are sometimes compatibility issues with older Adobe products, after using more recent Adobe software. Not only that, but PSD files are only compatible with other Adobe products.

AIStands For Adobe Illustrator

Used For/Example They are used a lot in print media for artwork and vector-based drawings. AI files are saved as Vectors. They are used by designers to create things for companies, such as cartoons, logos and illustrations.

Advantage They can be opened in programs like Adobe Acrobat and any other PDF reader.The files are vector based, so no matter what size the image is, it won't lose quality and become pixelated.

Disadvantage An AI file requires specialist software to open the file. This means that they can only be viewed on some occasions.

FLAStands For Flash File Format

Used For/Example These are movie or animation files that have been created using the Adobe Flash product. Very high quality animations can be made using these files. They are used for creating animations and games.

Advantage

Reference :Michael Bluejay. (2007). Video file

formats for the web compared. Available: http://websitehelpers.com/video/format

s.html. Last accessed 30th Nov 2015.

These files work equally as well on PC's and MAC's and any other devices. “More users have flash installed than any other media player”, so more of them could view a file in this format.They are high quality files, yet they can have a low file size. This means that they can be used on websites without slowing them down too much. These files can include both video and sound.

Disadvantage The files are very complex, and include a lot of information, so therefore they can take up a lot of storage space depending on certain circumstances. Only limited software can run these files.

WMFStands For Windows Metafile

Used For/Example A WMF is a graphics file format. They are used to store vector and bitmap information in memory, for playback later on. They can be used when creating logos and clipart.

Advantage They can contain both vector and bitmap information. They make the most out of the resolution of the output device. Can be resized with no distortion that can occur when resizing bitmaps.

Disadvantage Not many application are available that allow editing to take place on metafiles.WMF's are only available on Windows platforms.

File Format Capture and Optimising

CompressionDefinition Compression is when a digital file is reduced

in size. By doing this, you change the way that the data is coded. As a result of compression, more memory becomes available.

Advantage The file size is reduced, which frees up more memory. Due to a small file size, compressed files can usually be easy to send via email, and they can be used on webpages, without slowing them down too much.

Disadvantage The quality of the file will decrease. Images may come across as more pixelated, due to the fact that some of the image information (layer information etc.) can be lost and that less pixels are saved each time. Colour information can also be lost/changed.

Image CaptureMethod Scanner

How is it used for image capture of graphics They scan products, and pick up text, handwriting, imagery and objects, like paper and in doing so, they create a digital image, which is usually then edited and viewed on a computer. They are generally used for flat objects/documents as opposed to 3D objects.

Method Camera

How is it used for image capture of graphics Camera's are used to capture digital images. They use an electronic image sensor to do so. They tend to be portable, so using a camera, the photographer can take a photograph of almost anything. Cameras are used to capture 3D images, such as landscapes or family photographs.

Method Graphics Tablet

How is it used for image capture of graphics

This device allows users to hand draw images, similarly to drawing on paper. However it is digital, so the images are easily edited and usually come across as more professional. By using one of these you personally create a piece of artwork, rather than having the device create it for you. Using one of these you could draw or trace a piece of artwork and transfer it to your computer.

OptimisingWhy would you optimise? You would optimise an image for a website

in order to reduce the file size, so that the website can then run faster. This would mean that people can easily look at the image on a website.

How can you optimise? To optimise an image you can use image editing software such as Adobe photoshop to change the image dimensions. In adobe photoshop you would change the ‘image size’ and make sure that the image width was no larger than 500 pixels wide. You can also change the bit depth and the resolution.

Advantage to optimising Optimising an image can reduce the time it takes to download it. It does this by reducing the file size. If an image is optimised, it can help to make a website run faster, due to it’s low file size.

Disadvantage to optimising If you optimise an image, pixel information is lost. And after optimising you can not get that information back.

Storage

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

If there is a lot of information on the document, such as layers and colour information, the file size will be larger.

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

affecting quality?

You could convert the file to a lossless format, which would reduce the file size, without losing much, if any quality.

What is an advantage of scaling up images before exporting?

Scaling an image to be smaller before exporting, may be a good thing as some websites don’t allow large images, as they take up a lot of room.

What is a disadvantage of scaling up images before exporting?

If an image is scaled up too big before exporting, the image may lose quality and become pixelated. The file size may also become large and take up a lot of memory space.

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

When creating files, the names should include a short description of what the file is. It should also include a date of when I saved the file, and it should also include the creator's name.

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

It’s a good idea to name your files, so that when looking for the file next time, it is easy to find if you follow these conventions each time.

Asset ManagementWhy would you use folders when storing

your assets?When storing files, folders can be used to keep everything organised. Each folder can represent either a date, or a project that you’ve been working on. This way, files are easy to find. Using folders can make finding work a lot quicker and easier.

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

I would create a Media folder to hold all of my Media coursework. In that folder would be four other folders; Print based media, Photography, Video games, Work Related Learning and Video. In each of these folders I would include either weekly folders, or a folder or each different project for that specific unit of work. For example, I would save my rotoscoping work, in the rotoscope folder in my print based media folder.