Reduction of Data Representing One Pel Line
Original Publication Date: 1987-Aug-01
Included in the Prior Art Database: 2005-Feb-01
This article describes a method for reducing the number of bits for representing gray levels of pels (picture elements) in one scan line of a document by comparing the gray level of the succeeding pels to find out turning points, determining variations between (a) a virtual line connecting two pels at the turning points and (b) the gray levels of intermediate pels existing between the two pels at the turning points, and forming a data stream for each virtual line which includes the gray levels of the two pels, the number of the intermediate pels and the variations of the intermediate pels. Referring to Fig. 1, a horizontal axis represents pels of a document and a vertical axis represents gray levels which changes between level 0 and level 255. Exemplary gray levels Y0 through Y10 of pels X0 through X10 are shown.