Multilayered image file
AssigneeSharp Laboratories of America, Inc.
InventorKristine E. Matthews
Life of this patent
Estimating the term…
Abstract
To improve compression efficiency and decompressed image quality, images are decomposed into separate layers each containing a limited number of image element types (text, line art, or photographic). Each layer can then be compressed separately with a process that is optimal for the type of image element included in the layer. Images are decomposed into foreground, background, and mask layers. The value of a pixel in the mask layer designates whether the spatially corresponding pixel of the recomposed image will be selected from the spatially corresponding pixels of either the foreground or the background layer.
Claims23
A method of encoding an image comprising:
- (a) defining a first layer;
- (b) defining a second layer;
- (c) modifying said first layer by adding information from a mask layer;
- (d) encoding the modified said first layer;
- and
- (e) encoding said second layer separate from said encoded modified first layer.
A digital image file readable by a computing processor and representative of an image comprising:
- (a) a first encoded portion including a first layer and a mask layer encoded together;
- and
- (b) a second encoded portion including a second layer.
Dependencies are inferred from the claim text.