The document discusses key concepts for digital graphics in computer games such as pixel resolution, vector and raster images, file formats, compression techniques, image capture devices, optimizing performance, storage and asset management. It provides definitions and examples for each topic. The sources used to compile the information are cited at the end.

1. Unit 78: Digital Graphics for
Computer Games
By Jason Finch

2. Pixel and Resolution
• Image resolution is a term that describes the detail an image
holds. The term applies to raster digital images, film images,
and other 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 resolved. Resolution units can
be tied to physical sizes (e.g. lines per mm, lines per inch), to
the overall size of a picture (lines per picture height, also
known simply as lines, TV lines, or TVL), or to angular
subtenant.

3. Vector and Raster Images
• Vector graphics is the use of geometrical primitives such as points, lines,
curves, and shapes or polygon(s), which are all based on mathematical
expressions, to represent images in computer graphics. "Vector", in this
context, implies more than a straight line.
• In computer graphics, a raster graphics image is a dot matrix data
structure representing a generally rectangular grid of pixels, or points of
colour, viewable via a monitor, paper, or other display medium. Raster
images are stored in image files with varying formats.

4. File Format and Uses
• A file format is a standard way that information is encoded for storage in a computer file. A
file format specifies how bits are used to encode information in a digital storage medium.
File formats may be either proprietary or free and may be either unpublished or open.
• Some file formats are designed for very particular types 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 different types of multimedia, including any combination of audio and video, with or
without text (such as subtitles), and metadata. A text file can contain any stream of
characters, including possible control characters, and is encoded in one of various character
encoding schemes. Some file formats, such as HTML, scalable vector graphics, and the source
code of computer software are text files with defined syntaxes that allow them to be used
for specific purposes.

5. Compression
• In computer science and information theory, data compression involves encoding
information using fewer bits than the original representation. Compression can be
either be lossy or lossless. Lossless compression reduces bits by identifying and
eliminating statistical redundancy. No information is lost in lossless compression.
Lossy compression reduces bits by identifying marginally important information
and removing it. The process of reducing the size of a data file is popularly referred
to as data compression, although its formal name is source coding (coding done at
the source of the data, before it is stored or transmitted).

6. Image Capture Devices
• A camera is a device that records images that can be stored directly, transmitted to another
location, or both. These images may be still photographs or moving images such as videos or
movies. An early mechanism for projecting images. The modern camera evolved from the
camera obscura.
• Traditional cameras capture light onto photographic film or photographic plate. Video and
digital cameras use an electronic image sensor, usually a charge coupled device (CCD) or a
CMOS sensor to capture images which can be transferred or stored in a memory card or
other storage inside the camera for later playback or processing.
• Cameras that capture many images in sequence are known as movie cameras or as ciné
cameras in Europe; those designed for single images are still cameras. However these
categories overlap as still cameras are often used to capture moving images in special effects
work and many modern cameras can quickly switch between still and motion recording
modes. A video camera is a category of movie camera that captures images electronically
(either using analog or digital technology).

7. Optimising
• In computer science, program optimization or software optimization is
the process of modifying a software system to make some aspect of it
work more efficiently or use fewer resources. In general, a computer
program may be optimized so that it executes more rapidly, or is capable
of operating with less memory storage or other resources, or draw less
power.

8. Storage and Asset Management
• Memory management is the act of managing computer memory. The essential
requirement of memory management is to provide ways to dynamically allocate
portions of memory to programs at their request, and freeing it for reuse when no
longer needed. This is critical to the computer system.
• Several methods have been devised that increase the effectiveness of memory
management. Virtual memory systems separate the memory addresses used by a
process from actual physical addresses, allowing separation of processes and
increasing the effectively available amount of RAM using paging or swapping to
secondary storage. The quality of the virtual memory manager can have an
extensive effect on overall system performance.

9. Sources used
• http://en.wikipedia.org/wiki/Image_resolution
• http://en.wikipedia.org/wiki/Vector_graphics
• http://en.wikipedia.org/wiki/Raster_graphics
• http://en.wikipedia.org/wiki/Camera
• http://
www.promotionalmerchandise.co.uk/images/D/zoom_promotiona
• http://en.wikipedia.org/wiki/Data_compression
• http://en.wikipedia.org/wiki/Program_optimization
• http://en.wikipedia.org/wiki/Memory_management

10. Sources used
• http://en.wikipedia.org/wiki/Image_resolution
• http://en.wikipedia.org/wiki/Vector_graphics
• http://en.wikipedia.org/wiki/Raster_graphics
• http://en.wikipedia.org/wiki/Camera
• http://
www.promotionalmerchandise.co.uk/images/D/zoom_promotiona
• http://en.wikipedia.org/wiki/Data_compression
• http://en.wikipedia.org/wiki/Program_optimization
• http://en.wikipedia.org/wiki/Memory_management