Abstract: A method and apparatus for encoding an image is disclosed. In one embodiment, the method comprises identifying initial pixels within a spatially defined sub-section, the initial pixels at least a defined number of pixels each comprising a first color; identifying background pixels, the background pixels comprising the first color and in a first defined spatial proximity to the initial pixels; identifying text pixels, the text pixels contrasting the first color and in a second defined spatial proximity to the background pixels; identifying picture pixels as all pixels other than the background pixels and the text pixels; generating a background encoding comprising (i) spatial locations of the background pixels and (ii) a lossless encoding of the first color; generating a text encoding identifying a spatial location and a lossless color encoding of each of the text pixels; and generating a picture encoding comprising a lossy encoding of the picture pixels.

Abstract: A method and apparatus for encoding an image is disclosed. A decomposition circuit comprises a set of pixel filters used to identify picture pixels, background pixels and text pixels of the image. An image encoding circuit comprises a lossy discrete transform encoder for encoding the picture pixels, a constant color lossless encoder for encoding the background pixels, and a discrete color lossless encoder for encoding the text pixels.

Abstract: Decomposing a computer display image into different layer types and associated masks based on the unique nature of the image is disclosed. These types include text, objects, background and pictures. A set of image masks is used to uniquely identify different layer types within an image, where each layer type includes none, some or all of the pixels of the original image. Each layer of the image is processed prior to transmission (i.e. compressed) using a method appropriate for the characteristics of that layer.