3. BTec Level 3
Extended Diploma in Creative Media Production
HA1 - Technical File – Billie Dwyer
4. BTec Level 3
Extended Diploma in Creative Media Production
HA1 - Technical File – Raster and Vector Images
There are two kinds of computer graphics - raster (composed of pixels) and vector (composed of paths).
Raster images are more commonly called bitmap images.
A bitmap image uses a grid of individual pixels where each pixel can be a different colour or shade. Bitmaps
are composed of pixels.
Vector graphics use mathematical relationships between points and the paths connecting them to describe
an image. Vector graphics are composed of paths.
The larger you display a bitmap, the more jagged it appears,
while a vector image remains smooth at any size.
Raster Vector The jagged appearance of bitmap images can be partially
overcome with the use of "anti-aliasing". Anti-aliasing is the
application of subtle transitions in the pixels along the edges of
images to minimize the jagged effect . A scalable vector image
will always appear smooth .
Anti-Aliased Bitmap
Image: Smooth Vector Image:
5. Bitmap images require higher resolutions and anti-aliasing for a smooth appearance. Vector-based
graphics on the other hand are mathematically described and appear smooth at any size or
resolution.
Bitmaps are best used for photographs and images with subtle shading. Graphics best suited for the
vector format are page layout, type, line art or illustrations.
6. HA1 - Technical File – Antialiasing
Anti-Aliasing is a method of fooling the eye that a jagged edge is really smooth. Anti-Aliasing is often
referred in games and on graphics cards. In games especially the chance to smooth edges of the images
goes a long way to creating a realistic 3D image on the screen. Anti-Aliasing does not actually smooth
any edges of images it merely fools the eye.
Blown up letter a
with no anti-aliasing: Had anti-aliasing applied:
You can still tell that the letter of the left is jagged but the letter on the right looks a lot smoother and less
blurry than the example above. The image has been shrunk down back to normal size. Anti-Aliasing brings a
much more pleasing image to the eye. Something like what comes out of a high class printer rather than
what you can be used to seeing when on a computer screen.
7. HA1 - Technical File – Resolution
Resolution is the number of pixels in a linear inch—pixels per inch (or PPI), but it is most commonly referred
to as dots per inch (DPI). The more pixels, or “dots,” per inch, the higher your image resolution will be.
With colour images, each pixel can be one of 16 million different colours. For black and white images, there are
256 gradations of gray pixels ranging from black to white: 0 (black) through 255 (white). More pixels means
higher resolution, which creates better image quality because you end up with more realistic representations of
colour, better gradations of both individual colours and gray tones, and crisper images in general.
8. HA1 - Technical File – Aspect Ratio
The aspect ratio of a shape is the ratio of its longer dimension to its shorter
dimension. It may be applied to two characteristic dimensions of a three-
dimensional shape, such as the ratio of the longest and shortest axis, or for
symmetrical objects that are described by just two measurements, such as
the length and diameter of a rod. The aspect ratio of a torus is the ratio of
the major axis R to the minor axis r.
For a rectangle, the aspect ratio denotes the ratio of length to width of the rectangle. An aspect ratio of 1:1 is a square.
From left to right:
From left to right:
1.3 = 4:3: Some (not all) 20th century computer monitors (VGA, XGA,
etc.), standard-definition television
1.414… = √2:1: International paper sizes (ISO 216)
1.5 = 3:2: 35 mm film, iPhone displays
1.6 = 16:10, widely used widescreen computer displays (WXGA)
1.618…: Golden ratio, close to 16:10
1.6 = 5:3: super 16 mm, a standard film gauge in many European
countries
1.7 = 16:9: widescreen TV
9. HA1 - Technical File – File Formats
A file format is a particular way that information is encoded for storage in a computer
file.
Since a disk drive, or indeed any computer storage, can store only bits, the computer
must have some way of converting information to 0s and 1s and vice-versa. There are
different kinds of formats for different kinds of information. Within any format type,
e.g., word processor documents, there will typically be several different formats.
Sometimes these formats compete with each other.
File formats are divided into proprietary and open formats.
Some file formats are designed for very particular sorts of data: PNG files, for example,
store bitmapped images using lossless data compression. Other file formats, however,
are designed for storage of several different types of data: the Ogg format can act as a
container for many different types of multimedia, including any combination of audio
and/or video, with or without text (such as subtitles), and metadata. A text file can contain
any stream of characters, encoded for example as ASCII or Unicode, including possible
control characters. Some file formats, such as HTML, Scalable Vector Graphics and the
source code of computer software, are also text files with defined syntaxes that allow
them to be used for specific purposes.GIF – CompuServe's Graphics Interchange Format,
JPEG, JFIF (.jpg or .jpeg) – Joint Photographic Experts Group – a lossy image format
widely used to display photographic images, TIFF (.tif or .tiff) – Tagged Image File Format
(usually lossless, but many variants exist, including lossy ones), EPS is a DSC-
conforming PostScript document with additional restrictions which is intended to be usable
as a graphics file format, .psd (Photoshop document), the default file extension of the
proprietary file format of Adobe System's Photoshop program, Portable Document Format
(PDF) is a file format used to represent documents in a manner independent of application
software, hardware, and operating systems.
10. HA1 - Technical File – colour models
A colour model is an abstract mathematical model describing the way colours can be
represented as tuples of numbers, typically as three or four values or colour
components. When this model is associated with a precise description of how the
components are to be interpreted (viewing conditions, etc.), the resulting set of colors
is called colour space. This section describes ways in which human colour vision can
be modelled
RGB colour model
Media that transmit light (such as television) use additive
colour mixing with primary colours of red, green, and
blue, each of which stimulates one of the three types of
the eye's colour receptors with as little stimulation as
possible of the other two. This is called "RGB" colour
space. Mixtures of light of these primary colours cover a
large part of the human colour space and thus produce a
large part of human colour experiences. This is why
colour television sets or colour computer monitors need
only produce mixtures of red, green and blue light.
11. HA1 - Technical File – colour models
CMYK color model
It is possible to achieve a large range of colors seen by humans by
combining cyan, magenta, and yellow transparent dyes/inks on a white
substrate. These are the subtractive primary colours. Often a fourth
black is added to improve reproduction of some dark colors. This is
called "CMY" or "CMYK" color space.
The cyan ink absorbs red light but transmits green and blue, the
magenta ink absorbs green light but transmits red and blue, and the
yellow ink absorbs blue light but transmits red and green. The white
substrate reflects the transmitted light back to the viewer. Because in
practice the CMY inks suitable for printing also reflect a little bit of color,
making a deep and neutral black impossible, the K (black ink)
component, usually printed last, is needed to compensate for their
deficiencies. The dyes used in traditional color photographic prints and
slides are much more perfectly transparent, so a K component is
normally not needed or used in those media.
12. HA1 - Technical File – Adobe Photoshop
Photoshop is a popular image changing software package. It is
widely used by photographers for changing photographs (fix
colors, reduce noise, add effects, fix brightness/contrast) and by
graphic designers and Web designers to create and change
images for web pages.
Photoshop works on computer systems like Windows and Mac.
The software is made by the company Adobe. There is also a
version named Photoshop Elements, made for the home user that
does not want to buy the full version that is more expensive. The
current version is Photoshop CS5, which was released in April
2010.
13. HA1 - Technical File – Adobe illustrator
Adobe Illustrator is a vector graphics editor developed and
marketed by Adobe Systems. Illustrator is similar in scope,
intended market, and functionality to its competitors,
CorelDraw and Macromedia FreeHand
Versions 1–1.6 (Illustrator 88) Versions 6–10
Versions 2–5 Versions CS–CS5
14. HA1 - Technical File – 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 InCopy word
processor uses the same formatting engine as InDesign.
InDesign 1.0 (codenamed K2): August 31, 1999.
InDesign 1.5 (codenamed Sherpa): April 2001.
InDesign 2.0 (codenamed Annapurna): January 2002 (just days before QuarkXPress 5). First
version to support Mac OS X and native transparencies & drop shadows.
InDesign CS (codenamed Dragontail) and InDesign CS PageMaker Edition (3.0): October 2003.
InDesign CS2 (4.0) (codenamed Firedrake): shipped in May 2005.
InDesign Server (codenamed Bishop): released October 2005
InDesign CS3 (5.0) (codenamed Cobalt): April 2007. First Universal binary versions to natively
support Intel-based Macs, Regular expression, Table styles, new interface
InDesign CS3 Server (codenamed Xenon): released May 2007
InDesign CS4 (6.0) (codenamed Basil): Introduced September 23, shipped in October 2008.
InDesign CS4 Server (codenamed Thyme)
InDesign CS5 (7.0) released April 2010
InDesign CS5.5 (7.5) released April 2011