BINARY IMAGE REDUCTION METHOD

摘要

According to the present invention, provided a binary image reduction method, wherein when horizontal and vertical conversion ratios .alpha.x and .alpha.y are respectively given by: 1/nx > .alpha.x ? 1/(nx + 1) 1/ny > .alpha.y ? 1/(ny + 1) (where nx and ny are natural numbers) some or all of 2(nx + 1) x 2(ny + 1) original pixels are referred in horizontal and vertical directions to have a converted pixel as a central pixel to detect a thin line whose horizontal line width in an original picture is equal to or smaller than nx pixels and whose vertical line width in the original picture is equal to or smaller than ny pixels, and which has a length equal to or larger than a predetermined value in horizontal, vertical, and oblique directions, and a value of the thin line is substituted in a converted pixel closest to the thin line upon detection of the thin line.