Raster Image

A raster image is an image composed of a fixed grid of pixels, each assigned a specific colour. Photographs, scanned images, and most images viewed on screens are raster images. The quality of a raster image is determined by its resolution — the number of pixels in a given area — and its physical size. Scaling a raster image up beyond its native resolution causes visible pixelation as the software is forced to invent pixel information that does not exist in the original file. This is the fundamental limitation of raster formats for logo use. Professional logos are designed as vector artwork, which can be scaled to any size without quality loss. Raster versions of logos — typically PNG and JPEG files — are generated from the vector master at specific sizes for specific applications. While raster logo files are practical for everyday digital use, the vector source files are always the authoritative master.