techinal file raster and vector images

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  • 1.HA1 Technical File

2. Vector Images There are two different types of computer graphics, raster and vector. Vector graphics use mathematical relationships between points and the paths connecting them to describe an image. Vector graphics are composed of paths. Changing the attributes of a vectorobject will not affect the object itself, and you can freely change theattributes without destroying the original object. Because vector based images are scalable, they are resolution dependent, and by decreasing or increasing the lines, they will still remain as sharp, fresh lines. A type of vector object in font. The best thing about vector images is that they can be easily scaled without losing any of their characteristics. 3. HA1 - Technical File Becky Doyle Raster Images A raster graphic is bitmap which is an array of pixels with values indicating the colours, and the bitmap colours are defined in pixels. Since the sizes are measured in pixels, the print dimension depends on the resolution of the printer. BMP records every pixels in the image, so the size is very big even for small images. If you try and scale the image to a larger size, it degrades the image and you start to see all the pixels that make up the image. It does this because raster images have a fixed resolution and can not be resized without losing image quality. A bitmap is technically characterized by the width and height of the image in pixels and by the number of bits per pixel . Bitmap images tend to have larger file sizes than vector graphics as they are often compressed to reduce their size 4. Anti-aliasing Anti-aliasing is a method where the eye is fooled into thinking that a jagged edge is really smooth. It is often used in games and on graphics cards. The image on the right has been anti-aliased, and if you make the letter into standard size, you will see that the edges look fairly smooth. A downside to using anti-aliasing is that if on a game, this method has been used, it can slow the game down a lot. So its best to lower the number that you anti-aliased the objects as.Using this method brings a more pleasing experience to the users eye, as it genuinely look smooth. Little do they know that a bit of magic has been used to disguise the fact there are jagged edges. 5. Resolution Resolution describes the detail that an image holds, and it applies to raster digital images, film images and any other types of image. The higher the resolution, the more detail that is in the image. The resolution of an image is measured in pixels. Pixels are tiny dots/squares that are displayed together in on colour in millions of shades. The person that is viewing an image will see a nicely formed picture, and the pixels can only be visible if you zoom in to the image. Aspect Ratio The aspect ratio of a shape or image is the ratio of its longer dimension to its shorter one. 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. 6. File Formats Colour Models A file format is a particular way in which information is encoded for storage on a computer file. File formats includeGif, Jpeg, Tiff, Eps, PSD and PDF.Gif is a bitmap image format.Jpegis a commonly used method of lossy compression for digital photography. Tiff stanf for tagged image file format, this is used for storing images, and is popular among graphic artists. PSDis a Photoshop document. Itholds support for most imaging options available in Photoshop. The last one is PDF. This means portable document format, and is used representing documents in a manner independent of application software, hardware, and operating systems. Acolour modelis an abstract mathematical model describing the way colours can be represented as tuples of numbers, typically as three or four values or colour components. There are two types of colour models, those that aresubtractiveand those that areadditive . Additive colour models uselightto display colour while subtractive models use printinginks . Colours perceived in additive models are the result oftransmittedlight. Colours perceived in subtractive models are the result ofreflectedlight. 7. Adobe Photoshop Adobe Photoshop is a graphics editingapplicationpopular for it's extensive amount of features. Photoshop is also, currently, the leading graphics editing application.Photo shop is also an image creation software as well as an editor. Photo shop can create any effect or style needed in a drawing or painting or layout. There are graphic software that can do specialized work faster and moreefficientthan Photo shop (such as painter for realistic paint effects), but Photo shop can do it all in one program.The basics of Photo shop are easy to learn, even the CS versions. They are very intuitive, and there are several ways to do almost everything to work with an individual's style of drawing and skill level yet you can spend years learning all the pro level features.Photo shop works by altering individual pixels in an image as opposed to a vector drawing program that draws with points, lines and objects mathematically. Photo shop is best with images that have complex textures, blends and photo realism, but Photo shop is also very good at vector drawing as long as the image doesn't need to be scaled and you don't need specialized CAD drawing tools. 8. Adobe Illustrator Adobe Illustratoris a vector graphics editor developed and marketed by Adobe Systems. It is often used to draw illustrations, cartoons, diagrams, charts and logos. Unlike bitmap images that stores information in a grid of dots, Illustrator uses mathematical equations to draw out the shapes. This makes vector graphics scalable without the loss of resolution. Some advantages of vector graphics are they are scalable without losing resolution, they have crisp and sharp lines at any sizes and they are good for drawing illustrations. The use of mathematical equations to generate points, lines, curves and other shapes is a difference between Adobe Illustrator and other graphics software programs on the market. This technique is known in the jargon of the industry as "geometrical primitives" and is the basis of vector graphics. Contained within the software are a range of tools designed to allow a smooth interface between the user and the program. Using these tools, a competent operator can create brilliantly coloured artwork, cartoon drawings and all kinds of illustrations and graphic material. The developers of Adobe Illustrator kept terminology relatively simple for users by using familiar words such as text, blend, trace, pen, brush and mesh. 9. Adobe InDesign Adobe InDesignis 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.You can use the Gradient Palette in InDesign to create colours that change from one colour to another when applied to an object. InDesign is the perfect choice for making any document that needs some creative layout, from posters to newspapers. It offers all kinds of features to modify your text and images, which can work together in interesting ways to create a unique and professional design. 10. Bibliography 11. Bibliography

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