Computer Game GraphicsTechnical Files

Pixel andResolution

Image resolution is a term for the amount of detail an image holds. This term applies to raster images, vector images, film images and other types of images. Higher resolution means more detail and it can be measured in various ways.

Pixel resolution refers to the pixel count in digital imaging. To describe pixel resolution is when pixels are measured in the first column (width) and second column (height) for example an images pixel resolution might be 640 x 420. Another popular way of citing pixel resolution is by the number of pixels in an image.

Vector andRaster Images

There are two kinds of computer graphics, raster graphic (which is composed of pixels) and vector graphic (which is composed of paths). Raster images are more commonly known as a bitmap.

A raster graphic uses a grid of individual pixels which can be a different shade and colour. Whereas vector graphics use mathematical relationships between points and paths, connecting them to describe an image.

Bitmaps are best used for photographs and images with subtle shading and need a higher resolution than vector art which is more suited for page layout, type, line art and illustrations.

File Formats and uses

File format is the specific format in which an image is save. Each file format has its own unique characteristics, advantages and disadvantages. By defining the file format it will be possible to determine how many bits per pixel it can hold and any other additional information.

• BMP (Bit-map) is the standard raster file format for a Microsoft Windows application

• GIF (Graphics Interchange Format) is another bit-mapped graphics file format which is used by the internet and online message servers. GIFs support colours and various resolutions and also includes data compression.

• PNG (Portable Network Graphics) is a bit-mapped graphic that was originally made to replace the GIF as an image file

Format that did not require a patent license. It supports grey scale, palate based images and non-palate based images. PNG was designed for transferring images onto the internet and not for high quality print.

JPEG (Joint Photographic Experts Groups) is a lossy compression technique for coloured images which can reduce its file size to 5% but can lose some detail in the compression. It is the most common file format used by digital camera and other photographic capture devices.

File Formats and uses

• Tiff (Tagged Image File Format) is a file format for storing images and is popular among graphic artists. Originally run by a company called Aldus it is now under control of Adobe Systems. It is widely supported by image manipulation applications.

• PSD (Adobe Photoshop File) an image file created by Adobe Photoshop, a popular image-manipulation program. It may include image layers, adjustment layers, file information, key information and other Photoshop elements.

• PDF (Portable Document Format) is a file format created by Adobe systems and is now an open standard for electronic document exchange. When you covert documents, forms and graphics they look just like they would if printed but can also add interactive buttons, shields, audio and video.

• AI (Adobe Illustrator File) is a file extension for a vector graphic file format used in Adobe Illustrator a popular vector at application.

• EPS (Encapsulated Postscript File) is a graphic file format for exchanging images, drawings or even whole page layouts. An EPS file holds internally a description of such an object using the Postscript page description language.

Compression

File compression often comes in the form of a zip file. This compression system is very hand as it lets you reduce the overall bits and bites in a file. This is so it can be transferred over the web quicker or take up less space on a disk.

Image compression is essentially minimizing the size in bytes of a graphics file without affecting the quality of the image to a unacceptable level. As previously mentioned in the slides beforehand two most common compression graphic image formats are the JPEG and GIF format. When a text file or program can be compressed without the induction of errors up to a certain point is called a lossless compression. A single error can cause a lot of damage to the meaning of a file usually a small loss can be quite noticeable.

Image Capture Devices

Image capture devices are devices such as cameras and scanners that take an image and pixelate it so it can then be manipulated in computer program software's.

They share the same technology and takes light and focuses it via the lense onto the sensor made of silicon it is made up of tiny photisites that are sensitive to light. A photosite is usually called a pixel and there are millions of these in the sensor light.

Unfortunately photisites are colour blindAnd can only display the intensity of the light that hits its surface. In order to get a full colour image the sensor has to use a filter to look at the lights in its three primary colours. I combines them to create the full spectrum.

Optimizing

Image optimizing is using the most compressed yet visually acceptable image in the correct file format for the correct purpose.

Jpeg optimization is a lossy form of compression as the image information is degraded or lost. Jpeg compression is expressed in terms of percentage so a 100% is at it’s highest quality while lowest percentage loses tonal information and image detail.

GIF works by mapping the image to colour palette. The maximum number of colours available is 256 to 216 this is a small number of colours but it adds to the fact that GIF is a lossless compression file as relatively speaking with already a small number of colours compression doesn’t cause to much loss of image information.

Un-optimized Image

Optimized Image

Storage andAsset Management

You can store media files in many different places the most common being the internal hardrive of the computer but can also be stored in a company network drive, a pen drive for carrying files over to a computer not part of a network or an external hard drive which usually has a lot more memory then a pen drive. A new and very popular way of storing now is by cloud or skydrive.

Managing your assets are very important in professional settings so your media is well organized by appropriate name and date as well as the appropriate media file if needed to be passed on to another colleague. In terms of using a software such as Adobe Premiere or Lightwave Layout files are linked to a project so therefore need to be kept in an organizedFolder otherwise assets in a project could go missing or might not be updated.

A personal example is when I created some arcade machines in Lightwave modeller then took them over to layout I needed to make sure that all the customized surfaces I had created for them were in the same folder as the project otherwise they would have not showed up on the arcade machine leaving them in blank colours