Title:
【発明の名称】画像縮小装置
Document Type and Number:
Japanese Patent JP3048152
Kind Code:
B2
Abstract:
PURPOSE:To attain the reduction of a binary picture compensating the disadvantage of the projection method such as missing of a thin line by detecting it that a pattern of a reference picture element is a pattern requiring the predetermined correction with respect to an output value (projection) of the projection method around a noted picture element, and applying a positive or a negative correction value. CONSTITUTION:For example, 3X3 block data D1.1-D3.3 from a line buffer 1 as shown in figure (b) are inputted to a projection value calculator 2 and a correction value calculator 3. The projection value calculator 2 calculates a projection value sum by using matrix values a1.1-a3.3 as shown in figure (c) in a memory 5 according to equation I. The correction value calculator 3 uses the block data D1.1-D3.3 from the buffer 1 and the reduced picture element obtained already as reference picture element data and outputs a correction value mod. Then a correction projection value sum + mod is obtained by an adder 7, a comparator 4 binarizes the value of a threshold level memory 6 to output 1 or 0. Thus, in the case of a predetermined specific pattern, a positive or negative correction is applied to the projection value to prevent missing of a thin line.
Inventors:
Koji Hirabayashi
Mitsuru Maeda
Tadashi Yoshida
Akihiro Katayama
Mitsuru Maeda
Tadashi Yoshida
Akihiro Katayama
Application Number:
JP31169288A
Publication Date:
June 05, 2000
Filing Date:
December 08, 1988
Export Citation:
Assignee:
Canon Inc
International Classes:
G06T3/40; H04N1/393; (IPC1-7): H04N1/393; G06T3/40
Domestic Patent References:
| JP63156476A | ||||
| JP6022871A |
Attorney, Agent or Firm:
Giichi Marushima