This document provides information about various topics related to digital media production, including: - It discusses raster images and how they represent digital images as a series of pixels arranged in a grid, while vector images use geometric primitives. - It covers concepts like resolution, file formats, color models, and anti-aliasing as they relate to digital images. Common file formats discussed include JPEG, GIF, TIFF, EPS, and PSD. - Graphics editing and design software are described, including Adobe Photoshop, Illustrator, and InDesign. Their features and uses for image editing, vector graphics, and page layout are summarized.

1. BTec Level 3
Extended Diploma in Creative Media Production
HA1 - Technical File – Ashleigh Darlington.

2. BTec Level 3
Extended Diploma in Creative Media Production
HA1 - Technical File – Raster images.
A raster image, also called a bitmap is a way to represent digital
images. The raster image takes a wide variety of formats. A
raster image represents an image in a series of bits of
information which translate into pixels on the screen. These
pixels form points of colour which create an overall finished
image. When a raster image is created the image on the screen
is converted into pixels and each pixel is assigned a specific
value which determines its colour.
When a raster image is viewed, the pixels usually smooth out
visually for the user who sees a photograph or drawing, when
blown up the pixels in a raster image become apparent.
Depending on resolution, some raster images can be enlarged to
very large sizes, while others quickly become difficult to see. The
smaller the resolution, the smaller the digital image file, for this
reason people who work with computer graphics must find a
balance between resolution and image size.
Resolution refers to the number of pixels per inch (PPI) or dots
per inch (DPI) in the image. The higher the resolution the greater
the number of pixels, this allows a greater radiation of colour that
will translate better as the image is enlarged. The more pixels,
the more individual points of data to be stored, as well. For high
quality photography, a high DPI is preferred because the images
will look more appealing to the viewer. For small images which
do not need to be blown up, or when quality is not important, a
http://www.wisegeek.com/what-is-a-raster- low DPI can be used
image.htm

3. HA1 - Technical File – Vector images
Vector graphics is the use of geometrical primitives such as lines, curves, points
and shapes or polygons which are all based on mathematical equations to
represent images in computer graphics.
These are instances where working with vector tools and formats is the best
practice. There are times when both formats come together. An
understanding of the advantages and limitations of each technology and the
relationship between them is most likely to result in efficient and effective use
of tools.
Vector graphics formats are complementary to raster graphics, which is the
representation of images as an array of pixels as its typically used for the
representations of photographic images Vector graphics are stored as
mathematical expressions as opposed to bit mapped graphics which are
stored as a series of mapped 'dots', also known as pixels (picture cells) There
are instances when working with vector tools and formats is the best practice,
and instances when working with raster tools and formats is the best practice.
This example shows the effect of vector
Vector formats are not always appropriate in graphics work because devices such graphics versus raster graphics> The
as cameras and scanners produce raster graphics that are impractical to original vector based illustration is the
one shown at the left. The lower right
convert into vectors. image illustrates the same
magnification as a bitmap image.
Vector images can be scaled
indefinitely without degrading quality.

4. Anti-aliasing.
In digital signal processing, spatial anti-aliasing is the technique of minimizing the distortion
artefacts known as aliasing when representing a high resolution image at a lower resolution.
Anti-aliasing is used on digital photography, computer graphics, digital audio, and many
other applications.
Anti-aliasing means removing signal components that have higher frequency than is able to be
properly resolved by the recording (or sampling) device. The removal is done before sampling
at a lower resolution. When sampling is preformed without removing this part of the signal,
it causes undesirable artefacts such as the black and white noise near the top of figure 1-a
below.
In this approach, the ideal image is regarded as a
signal. The image displayed on the screen is taken as
samples, at each (x,y) pixel position, of a filtered
Above left: an version of the signal. Ideally, we would understand
aliased version of how the human brain would process the original
a simple shape.
Above right: an signal, and provide an image on screen that will yield
anti-aliased the most similar response by the brain
version of the
same shape.
Right: The anti-
aliased graphic at
5x magnification.

5. Image Resolution
Image resolution describes the detail an image holds. The term applies to
raster digital images, film, images, and other different types of images.
Higher resolution means more image detail.
Image resolution can be measured in various ways. Basically resolution
quantifies how close lines can be to each other and still be visibly
removed. Resolution units can be tried to physical sizes to the overall
size of the picture or to angular subtenant. Line pairs are often used
instead of lines, a line pair compromises a dark line and an adjacent line.
A resolution of ten lines per millimetre. Photographic lens and film
resolution are most often quoted in line pairs per millimetre.
Spatial Resolution:
The measure of how closely lines can
be resolved in an image is called spatial
resolution, and it depends on properties A classic test target
of the system creating the image, not used to determinate
just the pixel resolution in pixels per spatial resolution of
imaging sensors and
inch.
imaging sensors.

6. Aspect Ratio.
The aspect ratio of an image is the ratio of the width of the image to its
height, expressed as two numbers separated by a colon. That is for an x:y
aspect ratio, no matter how big or small the image is, the width is divided
into x units of equal length and the height is measured using the same
length unit, the height will be measured to be y units.
Aspect ratios are mathematically expressed as x:y and Xxy with the letter
particularly used for pixel dimensions. Cinematographic aspect ratios are
usually denoted as a decimal multiple of width vs. unit height.
The most common aspect ratios used today in the presentation of films in
movie theatres are 1.85:1 and 2.39:1
5 common
aspect ratios:

7. File Formats
A file format is the standard way that information is encoded for
storage in files on the computer . It specifies how certain bits are
used to encode information.
GIF: This stands for Graphics Interchange Format, it is a bitmap image format that was introduced by
CompuServe in 1987 and due to its wide support and portability it developed into widespread usage on the
World Wide Web. The format supports up to 8 bits per pixel, this allows a single image to reference a pallet up
to 256 distinct colours. It also supports animations. The colour limitation makes the GIF format unsuitable for
reproducing colour photographs and other images that have continuous colours, but it works better with
simpler images such as graphics or logos.
TIFF: This stands for Tagged Image File Format and this is used for storing images and it used mostly by graphic artists,
people in the publishing industry and both amateur and professional photographers in general. Tiff formats are widely supported
by image manipulation applications, by publishing and using page layout applications.
EPS: This stands for Encapsulated PostScript this is a conforming PostScript document that has additional restrictions which are
intended to be useful as a graphics file format. EPS files are more or less self contained. It is a standard graphics file format for
exchanging images, drawings (such as a logo or map) or even layouts of complete pages.
PSD This is a Proprietary File Format that is used to create and edit images in Adobe Photoshop, which is a Graphics Editing
Programme. It is a widely accepted format as it supports all available image types – Bitmap, RGB, Duotone, Grey scale, Indexed
Colour, CMYK, Lab, and Multichannel.
PDF: This stands for Portable Document Format and it was developed in the early 1900’s. It is used to
represent documents independently of application software, hardware and operating systems. Every PDF file
encapsulates a complete description of a fixed-layout flat document this includes: font, text, graphics and other
information.
JFIF: This stands for JPEG File Interchange Format and this is a standard image file format. It is a format for
exchanging JPEG encoded files compliant with the JPEG interchange format (JIF) standard. It solves some of
JIF's limitations in regard to simple JPEG encoded file interchange and as with all these files, image date with
them is compressed by using the techniques in the JPEG standard.

8. Color models.
A color model is am abstract mathematical model by describing the way colours can represented as tuples
of numbers, typically as three or four values or colour components. When the model is associated with a
precise description of how the components are to be interpreted.
CMYK Colour Model RGB Color Model
Recognizing that the geometry of the
RGB model is poorly aligned with the
Color color-making attributes recognized by
human vision, computer graphics
printing researchers developed two alternate
typically representations of RGB, HSV and
uses ink of HSL. HSV and HSL improve on the
color cube representation of RGB by
four colors: arranging colors of each hue in a radial
cyan, slice, around a central axis of neutral
magenta, colors which ranges from black at the
yellow, and bottom to white at the top. The fully
saturated colors of each hue then lie in
key (black a circle, a colour wheel.
The CMYK color model (process color, four
color) is a subtractive colour model used in
colour printing, and is also used to describe
the printing process itself. CMYK refers to the
four inks used in some color printing: cyan,
magenta, yellow, and key (black).

9. Adobe Photoshop
Adobe photoshop is a graphics editing program developed and published by Adobe
Systems incorporated.
Adobe Photoshop is released in two editions: Adobe Photoshop, and Adobe
Photoshop Extended, with the Extended having extra 3D image creation, motion
graphics editing, and advanced image analysis features.
Features
Photoshop uses color models RGB, lab,
CMYK, greyscale, binary bitmap, and
duotone. Photoshop has the ability to read
and write raster and vector image formats
such as .EPS, .PING, .GIF, and .JPEG.
Photoshop has ties with other Adobe
software for media editing, animation, and
authoring. Photoshop has ties with other
Adobe software for media editing,
animation, and authoring.

10. Adobe Illustrator
Adobe Illustrator is a vector graphics editor developed and marketed Adobe
Systems. Illustrator is similar in scope, intended market, and functionality to its
competitors, Corel Draw and Macromedia Free Hand.
Features
Among the new features included in Illustrator CS2 were Live Trace, Live Paint, a
control palette and custom workspaces. Live Trace allows for the conversion of
bitmap imagery into vector art and improved upon the previous tracing abilities.
Live Paint allows users more flexibility in applying color to objects, specifically
those that overlap. In the same year as the CS2 release, Adobe Systems
announced an agreement to acquire Macromedia in a stock swap valued at about
$3.4 billion and it integrated the companies' operations, networks, and customer-
care organizations shortly thereafter. Adobe now owned FreeHand along with the
entire Macromedia product line and in 2007, Adobe announced that it would
discontinue development and updates to the FreeHand program. Instead, Adobe
would provide tools and support to ease the transition to Illustrator.

11. Adobe Indesign
Adobe InDesign is a software application produced by Adobe Systems. It can be
used to create works such as posters, flyers, brochures, magazines, newspapers
and books. In conjunction with Adobe Digital Publishing Suite InDesign can publish
content suitable for tablet devices. Graphic designers and production artists are the
principal users, creating and laying out periodical publications, posters, and print
media. It also supports export to EPUB and SWF formats to create digital
publications, and content suitable for consumption on tablet computer devices. The
Adobe in copy word processor uses the same formatting engine as InDesign.