Patent ID: 8515166

Claim:
A method of compressing a 2×2 block based binary image, the method comprising: determining whether each pixel included in a block corresponds to existing patterns included in an existing block using a computer processor; generating a number N of pixels of the block that are included in the existing patterns using a computer processor, wherein N is a natural number; and when N is more than a predetermined value, compressing the block to a binary bit stream using a computer processor, the bit stream comprising information of patterns of the pixels included in the existing patterns and color information of the pixels having a new pattern, wherein the binary bit stream further comprises: mode information indicating whether the binary bit stream includes compressed binary image information; sub-mode information indicating whether the existing pattern is used; pattern information indicating whether first through N th pixels are included in the existing patterns, wherein the pixels included in the block are sequentially denoted as first through M th pixels, wherein M is a natural number higher than N; information about N; pixel pattern type information indicating in which pattern of the existing patterns the N pixels are included; and color information for the pixels having the new pattern.