HA1 Task 1 - Technical Glossary

Task 1

VECTOR IMAGES: Vector Images use points to create images; these points can connect through curves or just being plain straight. It relies on a mathematical relationship between the points and paths that connect. The file formats for vector images are eps, wmf, fla, svg, ai. Vector shaped images can be scaled to any size both large and small.

RASTER IMAGES/BITMAP IMAGES: A Bitmap image can also be known as a raster image. A Bitmap image is the exact opposite of a Vector image. Bitmap images are made up of lots of pixels placed together; these pixels can each be different colours and shades as to create the patterns needed. They cannot be different sizes; each pixel can only be the same size as the pixel next to it.

Bitmap images cannot be scaled larger as well as the quality of the image will come out less smooth and blockier. However, the image will be able to be scaled down to a smaller size as this makes the pixels smaller having the image looking smooth.

THE PIXEL: The term pixel is short for “picture element.” A pixel is usually referred to as a dot since it has a minute area that the pixel will colour; another name for pixel is a bit. A Raster/bitmap image is usually made up of pixels. Screens for TV’s and monitors will use pixels to portray its images, these screens will consist of thousands of pixels as to get a clear image since people would prefer to see smooth images compared to blocky ones. However, if you set your resolution to a low one you can see the images start to become pixelated.

COLOUR DEPTH: Colour depth can also be known as bit depth, it is used to describe the numbers of colours used in an image, video, GIF etc. The scheme of bit/colour depth goes like this:

• If an image has 1 bit, then it holds 2 colours. These images and videos are usually in black and white.
• If an image has 2 bits then the images holds 4 colours and the image usually looks very grey with hints of white and light shades of grey.
• If an image has 4 bits then the image holds 16 colours. This is where colour begins to show although it can look quite pixelated.
• If an image has 8 bits then the image holds 256 colours, this is just a higher quality then 4 bits where you can begin to see the resolution become less pixelated.
• Finally, you have 24 bits, this has 16,777,216 colours and is also known as true colour. This is where images and videos become high quality and we begin to get resolution such as 720p.

The bits can go higher but the human eye can only distinguish between 10 million different colours so saving an image higher than 24 bits is a bit excessive.
                                                                                                                                                

COLOUR MODELS: Colour models are mathematical abstract ways on how to describe and define the ways in which colours will appear on a screen. Three popular colour models are:

• CMYK (Cyan, Magenta, Yellow, Black)
• RGB (RED, Green, Blue)
• Lab Colour

CMYK is mainly used when printing off work such as brochures or posters, they use this colour model because by combining these four colours and varying the percentages of each one. Different illusions of many colours can be made making the printed work seem more colour and eye catching for companies to gain attention from their audiences. CMYK is known as a "subtractive" colour model.

The RGB model is used when working with screen based designs, the colours here use a value of 0 to 255 so say you wanted full blue on your picture then you'd set the percentage of green and red to 0 and put the percentage of blue all the way up to 255. RGB is known as an "additive" colour model.

Lab Colour is made up of three components and is the most complex one of them all to use. The first component is the lighness which ranges from 0 to 100 and lets you decide or how light or dark you wish the image to be, the second component is the "a" component and comes from the green-red axis in the adobe picker, the finl compent is the "b" component and comes from the blue-yellow axis in adobe picker. Both the second and third component can range from +127 to -128. When photoshop is converting from one model to another, it uses Lab as the intermediate colour model.

RESOLUTION: Resolution comes down to the number of pixels shown on a screen, the lower the resolution the more pixels will be seen giving the image a chunky and bad quality look. It is expressed by the number of pixels on the horizontal and vertical axis. The higher the numbers on both axis then the better the quality (resolution) of the image. The resolution depends on the monitor and the size of it. This will also determine the sharpness of the image.

ANTI-ALIASING: It is a software technique used to get rid of jagged and stair stepped lines on the outside of an image to give it a smooth and sharper look. When it is not smooth the edges are known as jaggies and jaggies usually occur when the output device, monitor or printer doesn't have a high enough resolution to represent a smooth line. It removes the jaggies by surrounding the stairsteps with a immediate shade of grey or colour. However, this then makes the image look fuzzier. Anti alising is sometimes known as oversampling.

ASPECT RATIO: The aspect ratio is where the size of a geometric shape is measured. The ratio of the of the sizes of the different dimensions. E.g. the aspect ratio of a rectangles ratio would be it's longer side to it's shorter side (ratio of height to width). Ratios are set out in this fashion x:y. The numerical numbers are represented by x and y and are split apart by the colon in the middle. A square has the smallest possible aspect ratio of 1:1. Widescreen computers usually use the aspect ratio of 16:10 which also equals 1.6.

FILE FORMATS: File formats are documents which are saved in a certain way to store information. There are tons of formats within which a document can be saved and each one holds a special purpose of why it has that format. It's like an encryption that can only be opened using the correct software e.g. an ai file is usally saved in illustrator when you want to go back and edit a picture. This format is specific to Adobe illustrator in general and if tried opening with any other software (e.g. Photoshop) then it would not be allowed. After the editing is done the file can be saved under a different format such as a JPEG. This is because Formats need to be changed so that it allows for different options. We save files as JPEGS to compress an image and make it so we can use in other areas. -  bmp, png, gif, tiff, jpg, psd, pdf, eps and ai

COMPRESSION: Compression is where you reduce the size of a file and make it take up less memory. You compress the image to allow for more images to be stored in your memory.

IMAGE CAPTURE DEVICES: Image capture devices are also known as cameras. They are used to capture or take a picture of a real life event for you to hold onto or edit. People take pictures all the time using their cell phones, it basically works like the eye (which is what it is based off) and captures the moment that you took it so it stays with you, people take pictures of their faces, locations, everyday objects and of everything for many different reasons. As time has gone by the resolution of cameras has gone up with the first camera being very low in resolution and colour bit. It uses light to project an image upside down and then flips the image so it is the right way up such as what the eye and brain does for humans.

OPTIMISING: Optimising is where you try to get something to its full potential or maximum quality. Computers optimise by writing or rewriting code to maximise the efficiency, speed in retrieval, storage or execution (and more) so that it works better for people to use. Optimising an image can resort back to compression as that optimises a picture by getting rid of the massive amounts of memory an uncompressed image uses.

STORAGE AND ASSET MANAGEMENT: Storage management is abouth the processes and organisations of data storage resources. It is a broad category that includes virtualization, replication, mirroring, security, compression, traffic analysis, process automation, storage provisioning and related techniques. Asset management is a systematic process of deploying, operating, maintaining, upgrading, and disposing of assets cost-effectively. This just means that you upgrade and maintain a good system while using your time productively and spending as little money as possible.