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Digital Graphics File FormatsMillie Casemore
Raster GraphicsRaster graphics are essentially an image
created/made up by bitmaps. Bitmaps are made up of pixels which store a colour corresponding to the
image it makes up. They have a set resolution, for example 300dpi. Therefore, a disadvantage is when
being resized they can become distorted because the pixel are being stretched (less pixels per inch).
However an advantage of Raster graphics is that they can create complex, high quality images if they are
not resized.
Vector GraphicsVector graphics are images made up by paths and
strokes through mathematical formulas. They are made up of set start and end points and are connected by
lines (straight of curved). The lines can have different thicknesses and colour. An example of Vector graphics
is clipart, which are simple images created through vector graphics. An advantage of this is when being
resized, no image quality is lost. Also they have a small file size. However they are not good for creating
detailed images.
ResizingRASTER GRAPHICS
VECTOR GRAPHICS
The image here, after being resized, has clearly lost quality
and is not as clear as the image on the left.
Whereas here the image, after being resized, has
lost no quality and is still as clear as the image on
the left.
Raster Graphics
JPEGStands For Joint Photographic Expert Group
Used For/Example JPEG is a file format commonly used for images often posted online or to be saved to a computer. Eg. Facebook uploads.
Advantage/s • Small file size• Colour depth of 8 bits (256 colours
per channel)• Universally compatible
Disadvantage/s • Has a lossy compression algorithm meaning when it is compressed data is deleted from the image.
• However in comparison to RAW files, they have a small colour depth (8 bits compared to 10/12 bit)
TIFFStands For Tag File Image Format
Used For/Example Commonly used in the publishing/printing industry
Advantage • Option of lossless compression algorithm meaning they loose no data upon compression
• Can store high quality images without data being lost
• Suitable to store the working project without data being lost
Disadvantage • Large file size due to lossless compression
• Not suitable to store the ‘finished product’
• Not universally compatible/not as widely accepted as JPEG
GIFStands For Graphic Interchange Format
Used For/Example Commonly used for short clips of animations
Advantage • 8 bit colour depth• Suitable for logos and images with few
different colours• Good for short animations• Lossless compression
Disadvantage • Low quality if high amounts of colour are in the image
BMPStands For Bitmap Image File
Used For/Example Used to store images (bitmap files) and is very similar to JPEG and TIFF. Often used for printable images.
Advantage • Lossless compression so no data is deleted
• Produce high quality images
Disadvantage • Large file which cannot be compressed, particularly if there is a lot of colours
• Resizing the image usually results in a distorted image due to the bitmap/raster graphic file format
Vector Graphics
PSDStands For Photoshop Document
Used For/Example Used by magazine creators and publicists to create front covers, logos and to manipulate photos
Advantage • Can save multiple layers and page formatting information
• Good for working products• Lossless compression• Supports transparent
images/backgrounds
Disadvantage • Not suitable for final product• Large file size• Only compatible with Adobe
file formats/programs meaning not many programs will open PSD files
AIStands For Adobe Illustrator Art
Used For/Example Commonly used by digital artists to create for example logos
Advantage • Uses vector so images can be scaled to be either large or small and no image quality will be lost
Disadvantage • Not as widely compatible
• Specialist software (like adobe products) is needed
FLAStands For Flash File
Used For/Example Used to create basic games and animations, for example mini clip flash games
Advantage • High quality images/animations can be created
• Ideal for the web due to small file size• Can support video and sound
Disadvantage • Difficult to create and execute• Require specialist software
WMFStands For Windows Metafile
Used For/Example Used to create company logos by digital artists and companies. Similar to AI files
Advantage • Can contain both bitmap and vector images
• Images can be scaled large or small with no definition lost using vectors
Disadvantage • It is a low resolution image and is will create poor quality image is resized as a raster graphic
• Limited to only Microsoft programs to load up metafiles
File Format Capture and Optimising
CompressionDefinition Lossy compression reduces the file size
significantly by deleting data which is irrelevant therefore compressing the image. Whereas lossless compression reconstructs the file making it smaller but not deleting redundant data.
Advantage • Reduces the file size so it takes up less space on the hard drive and means the image is more suitable for the web.
Disadvantage • Due to data being deleted image quality is lost because pixels have been removed/deleted. Each time the file is opening more pixels are removed and over a period of time the image begins to become pixelated.
Image CaptureMethod Scanner
How is it used for image capture of graphics
A scanner shines light on an image (photos, sketches, writing) and digitises the image. The digitised image is then saved on the computer.
Method Camera
How is it used for image capture of graphics
Cameras are used to capture images by light entering the camera lens and the camera saves the data of each pixel using a sensor. Higher the megapixel, the higher quality image.
Method Graphics Tablet
How is it used for image capture of graphics
Graphics tablets allow users to directly draw onto the tablet or they a pen and display the image on a screen. This is a digital image and saved onto the hard drive.
OptimisingWhy would you optimise? Images are optimised to make for viewing
on the web easier and to reduce the file size so download time is shorter.
How can you optimise? Images can be optimised by changing the ‘image size’ in Photoshop. This includes changing the colour depth, resolution and using lossy compression to delete data.
Advantage to optimising Images, when optimised, will have smaller file sizes and reduce the time to it takes download the image.
Disadvantage to optimising However when images are optimised image quality is lost because the resolution will be lowered and various other components which make the image high quality.
Storage
File SizeWhat could affect a Working Scale (Photoshop) document file size?
• Number of layers and whether they’re merged
• Resolution of file• Whether unnecessary parts of layers
are cropped or not• Rasterising smart objects • Amount of colour/colour depth
How could you reduce the file size of a Working Scale document without
affecting quality?
• Using vector graphics so when resizing no image quality is lost
• Merge layers together • Delete excess data which is redundant
What is an advantage of scaling up images before exporting?
• Larger image for easier viewing• Consistent/same image quality (no
quality/data lost)
What is a disadvantage of scaling up images before exporting?
• Larger file size which can affect loading time on the internet
• Although no data is lost, pixels may be stretched because they’re being manipulated bigger
File Naming ConventionsWhat naming conventions could you use when creating your video game assets?
• Don’t use overcomplicated file names, straight to the point
• Use dates when the file was created• Abbreviate the file content• Use hyphens to separate each detail of
the file (date, content)• Don’t use spaces• If there is numerous file version,
number which version it is and the date is was created/modified
Why is it a good idea to accurately name your assets?
It is a good idea to name your assets so you can find certain files easily and efficiently. You can do this by searching for the file name/what your need and, if named correctly, you should find the asset.
Asset ManagementWhy would you use folders when storing
your assets?Using folders, when sorting assets, increases efficiency when finding particular files. This is because you can save files in folders and subfolders which are named appropriately. For example in your pictures folder you could have a subfolder called ‘Photoshop’ so you can easily access/find all your Photoshop files. Also it means you can directly search for specific files in these folders.
What folders would you create and what would you save within them
• In documents I would have a folder named ‘Media Coursework’ and within that folder I’d have folders named after each project. Within each folder there are subfolders containing each different part of the project (research, design, product). These files will all be named appropriately and be named after the folder their in e.g.. RESEARCH – Logo.
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