HA1 - Technical File – Raster & Vector Images A raster image is a way to represent digital images. A raster image represents an image in a series of bits of information which translate into pixels on the screen. These pixels form points of colour which creates an overall finished image. When a raster image is created, the image on the screen is converted into pixels, The raster image system uses red, green and blue. When a raster image is viewed, the pixels usually smooth out visually for the user, who see’s a photograph or a drawing. When blown up, the pixels in a raster image become apparent. Depending on resolution, some raster images can be enlarged to very large sizes, while others quickly become difficult to see.
HA1 - Technical File – Raster & Vector Images A vector image is the use of geometrical primitives such as points, lines, curves and shapes or polygon which are based on mathematical equations to represent images in computer graphics. Computer displays are made up from grids of small rectangular cells called pixels, the picture is built up with these cells. The smaller and closer together the cells are the better the quality if the image, but the bigger the file need to store the date. If the number of pixels is kept the size of the file generated will depend on the resolution required but the size of the vector file generating the bitmap/raster file will always remain the same.
HA1 - Technical File – Ant Aliasing Anti aliasing is a method of fooling the eye that a jagged edge is really smooth. It is often in games and on games graphic cards. The chance to smooth edges of images especially in games, it creates a realistic 3D image on the screen. Anti aliasing does not actually smooth edges of the images it merely fools the eye. The jagged edges are caused by limitations in computer screen. Monitors are capable of producing nearly perfect straight lines either horizontal or vertical, but when it comes to diagonal lines any angle your monitors is not capable of producing a line without some jagged edge. This is because your screen is made up of pixels in a grid form. When you draw a diagonal line on the computer screen it has to cross several grid lines, this is because pixels create blocks of coloured diagonal lines and displace this blocks slightly causing jagged lines.
HA1 - Technical File – Resolution Image resolution describes the detail an image holds. This applies to Raster digital images, film images and other types of images. Higher resolution means more image detail. It can be measure in various ways. Resolution quantifies how close lines can be to each other and still be visible resolved. Resolution can be tied to physical sizes like lines per inch or per mm , to the overall size of a picture lines per height or to angular subtenant. Line pairs are often used instead of lines, a line pair comprises a dark line and an adjacent light line. A resolution of ten times per millimetre means 5 dark lines alternating with 5 light lines or 5 line pairs per millimetre.
HA1 - Technical File – Aspect Ratio The aspect ratio of a shape is the ratio of its longer dimension. It may be applied to two characteristics dimensions of a three dimensional shape.
HA1 - Technical File – File Formats A file format is a particular way that information is stored on the computer in a file. Since a disk drive or indeed any computer storage, can store only bits, the computer must have some way of converting information. There are different ways of formats for different kinds of information, sometimes these formats compete with each other. GIF File Format: Conceptually, a GIF file describes a fixed sized graphical area populated with zero or more ‘images’. Many GIF files have a single file that fills the entire logical screen, others divide the logical screen into separate sub-images. These images may also function as animated frames in an animated GIF file, these also don't fill the logical screen. JPEG File Format: JPEG compression is used in a number of image file formats. JPEG/Exif is the most common image format used by digital cameras and other photographic image capture devices; along with JPEG/JFIF, it is the most common format for storing and transmitting photographic images on the World Wide Web.
HA1 - Technical File – Colour models A color model is an abstract mathematical model describing the way colors 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, the resulting set of colors is called color space. This section describes ways in which human colour vision can be modeled. Media that transmit light use additive color mixing with primary colors of red, green, and blue, each of which stimulates one of the three types of the eye's color receptors with as little stimulation as possible of the other two. This is called "RGB" color space. Mixtures of light of these primary colors cover a large part of the human color space and thus produce a large part of human color experiences. This is why color television sets or color computer monitors need only produce mixtures of red, green and blue light. 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 colors. 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 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.
HA1 - Technical File – Adobe Photoshop Adobe Photoshop is a graphics editing program. The newest version of Adobe® Photoshop® CS5 software redefines digital imaging with breakthrough tools for photography editing, superior image selections, realistic painting, and more. And now, use it with creativity-boosting mobile apps. Photoshop uses colour models RGB, lab, CMYK, greyscale, binary bitmap, and duotone. Photoshop has the ability to read and write raster and vector image formats such as .EPS, .PNG, .GIF, and .JPEG. Photoshop has ties with other Adobe software for media editing, animation, and authoring. Photoshop CS4 features are a new 3D engine allowing painting directly on 3D models, wrapping 2D images around 3D shapes, converting gradient maps to 3D objects, adding depth to layers and text, getting print-quality output with the new ray-tracing rendering engine. It supports common 3D formats; the new Adjustment and Mask Panels, Content-aware scaling, Fluid Canvas Rotation and File display options.
HA1 - Technical File – Adobe Illustrator Adobe® Illustrator® CS5 software helps you create distinctive vector artwork for any project. Take advantage of the precision and power of sophisticated drawing tools, expressive natural brushes, and a host of time-savers.
HA1 - Technical File – Adobe InDesign Adobe® InDesign® CS5.5 software lets you design and pre-flight engaging page layouts for print or digital distribution with built-in creative tools and precise control over typography. Integrate interactivity, video, and audio for playback on tablets, Smartphone's, and computers.