raster images: Also known as bitmap images, are composed of small squares, known as pixels, that lie on a grid. These images are resolution dependent – they represent a fixed number of pixels. As a result, they can appear jagged and lose detail if they are scaled on-screen or if they are printed at a higher resolution than they were created for. Raster images are created by scanning or by using a paint program such as Adobe Photoshop.

Digital Asset Management: consists of tasks and decisions surrounding ingesting, annotating, cataloguing, storage and retrieval of digital assets, such as digital photographs, animations, videos and music. Digital asset management systems are computer software and/or hardware systems that aid in the process of digital asset management.

Colourization: A process which allows painting a black/white or even a color video image with artificial colors

Colour Space: A two or three dimensional geometric representation of colors that can be seen or generated. RGB is an example of a two dimensional color space. LAB is a three dimensional color space.

Bit Depth in images: This refers to the color or gray scale of an individual pixel. A pixel with 8 bits per color gives a 24 bit image. (8 Bits X 3 colors is 24 bits.) CCD are colored in a pixel by pixel method.

Pixel: Picture element. The smallest unit (point) of an image displayed on screen. The quality of an image depends on the number of pixels per inch that make up the image

Pixellation: In computer graphics, pixelation is an effect caused by displaying a bitmap or a section of a bitmap at such a large size that individual pixels, small single-colored square display elements that comprise the bitmap, are visible to the eye.
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