1. Portfolio Task 5
By Emma Rigelsford

2. What is Digital Imaging?
• Digital images are objects which communicate
meaning or information.
• If an image is used or to be used on a
computer it is in digital form
• A photograph from a camera is a natural
image however once on a computer it is
manipulated into digital format.

3. What are Raster Images?
• Raster images can also be referred to as
bitmap images
• They are created on a computer with the use
of pixels
• Pixels are arranged in a small grid formation
where their colours and tones combine to
produce an image
• They are best for complex images or
photographic images
Example
Raster Image -

4. What are Vector Images?
• Vector images are created using mathematical
calculations on a computer
• Vector uses both line direction and magnitude
to create simple shapes i.e. lines, arcs
• These shapes can also be joined (combined)
together to make squares and circles as an
example.
Example
Vector
Image -

5. Advantages/Disadvantages for Raster
Images
Advantages:
• Ideal for professional photographic images which
contain a lot of colour
• More editing tools available to the consumer
• Can easily edit colour by seeing the individual
pixels making the image.
Disadvantages:
• Resolution dependent, can have pixels become
visible when the quality has been reduced
• The size will determine how much can be altered

6. Advantages/Disadvantages for Vector
Images
• Advantages
• More Flexible than raster images
• Smaller than raster files as they produce less information
when displayed/ edited
• Disadvantages
• To be viewed on computer they must be transformed into
pixels.
• Computer monitors can only show pixels so the computer
has to re-calculate the vector images to fit on the screen.
• The Computer must re-calculate the vector image every
time it refreshes.

7. What are Image file formats?
• Image file formats are the organizing of digital
images which allows a computer to tell what type
of data is stored in the current file selected.
• There are 5 types of Image file formats:
• .bmp – Bitmap
• .tif
• .gif
• Jpeg
• png

8. Advantages / Disadvantages of the
image file formats
• Used for: Natural Photographical images
• Name : JPEG
• Advantages:
• Compressed and take up less room
• Are a common file accepted by most websites
• Make the file smaller so they can be used in an email
JPEG – Disadvantages:
• The colour is slightly degraded once conversion from
normal image
• Designed for mainly websites and emails.

9. Advantages / Disadvantages of the
image file formats continued
• Used for Can be animated, used for large areas / solid
colours
• Name :GIF
• Advantages
• Great for websites
• Can make amusing images which are created from
movie clips
• Cross platform usage and made for online purposes
• Disadvantages
• Limited Colour availability
• Definitely not suited for high photographic images

10. Advantages / Disadvantages of the
image file formats continued
• Use: To save images to be read by multiple devices and to
get the max resolution and quality for the image.
• Name:TIFF
• Advantages
• High Quality images
• Saves the pristine full colour of the original photograph on
the camera
• Great for printing out large canvas prints of desired image
• Disadvantages
• Not suitable for most websites
• Extremely large file sizes from the colour

11. References
• Images:
• Vector Paris Image visited : 14/3/12
http://trialx.com/curetalk/wp-content/blogs.dir/7/files/2011/05/diseases/Vector-
3.jpg
• Raster Linux Head Image visited : 14/3/12
http://keithp.com/~keithp/talks/xr_ols2003/html/tux_head_raster_4x.png
Information:
Applied It 2A Moodle groups website Visited throughout the week of Week 8
Used the documents:
Raster Vector
Colour
Digital Imaging
Also visited:
http://amath.colorado.edu/computing/graphics/understand_fmts.html
14/3/12