Patent ID: 6094453
Filing Date: 2000-07-25
Classification: G06T,H04N

Abstract:
A method of encoding and compressing digital data comprising the steps of:representing an image as a group of pixels, each pixel expressed in a truncated format;dividing the group of pixels into elemental blocks of pixels suitable for compression;storing a base image representing a reference for comparison of successive images to detect change in the successive images;encoding changes from the base image by storing the location of any change and the value of changed data, the location of any change being stored in a header file;compressing the stored header file and changed data using a quad-tree format;generating a signal representing the compressed header file and changed data;receiving the compressed header file and changed data:decompressing the compressed header file and changed data;decoding the changes from the base image;applying a proportional dither routine to smooth background intensities in the changed image; andrestoring the changed image based on the location of any change and the value of changed data.