METHOD AND APPARATUS FOR QUICKLY SEARCHING CHANGING ELEMENTS, ESPECIALLY REGARDING TO REDUCING TIME REQUIRED FOR SEARCHING LINE DATA

摘要

PURPOSE: A method and an apparatus for quickly searching changing elements are provided to reduce time required for searching line data by omitting search for unnecessary changing elements in transmitting and receiving line data in a facsimile. CONSTITUTION: A first changing element of a current line and a first changing element of a previous line are searched(10). It is judged whether a data compression mode is a vertical mode(12). If so, line data are formed and a location of an observed pixel is updated(14). If not, a second changing element of the current line and a second changing element of the previous line are searched, and the searched changing element of the current line or previous line is decided as a new changing element to the observed pixel to be updated(16). It is judged whether the location of the observed pixel is an end of the width(18).