| 摘要 |
<p>An image processing apparatus includes a dither processor (l4), which converts an electrical signal (l2) representing a continuous-tone input image into a binary image signal (l6) by a dither method using a dither matrix. The binary image signal (l6) is stored in a memory (l8), and supplied to a pixel-density conversion processor (20), which converts a pixel-density of the binary image signal at a predetermined ratio, and generates a converted image with the pixel coordinates as defined by the conversion ratio. A pixel coordinate calculator (22) calculates a coordinates position of each pixel of the converted image in the binary image, and selects a fiducial pixel. Reference pixel selector (24) defines a window area on the binary image containing the fiducial pixel and corresponding in size to the dither matrix size, and extracts reference picture elements in the window area. A calculator (26) calculates an average image-density of the reference picture elements and generates density data, which is binarized by a second dither processor (28) by using a second dither matrix. </p> |
