JPS6462970A - Two-dimensional encoding system - Google Patents

Abstract

PURPOSE:To increase an encoding speed by considering the necessity of a b2 changing point detection in two-dimensional encoding. CONSTITUTION:An image data compression processing part 1 contains an image data input part 11, an encoding part 12, an encoding data output part 13, and a control part 14. The encoding part 12 is composed of a changing point detecting circuit 121 to detect the changing point of the colors from a white to a black or from the black to the white, a two-dimensional encoding circuit 122 to encode under the control of the control part 14, and a code selecting circuit 123 to select a code by the control of the two-dimensional encoding circuit 122, and a division into a vertical mode, a horizontal mode, and pass mode is executed by the b2 changing point detection. Thereafter, whether the pass mode is generated or not at the time of the vertical mode is checked, and when it is not generated, the encoding speed can be speeded up by omitting the b2 changing point detection.