Title:
NOISE REDUCING CIRCUIT
Document Type and Number:
Japanese Patent JPH01122273
Kind Code:
A
Abstract:
PURPOSE:To prevent a noise reduction processing from being unnecessarily executed and to prevent the rounding of an edge or the generation of an after- image by controlling the noise reducing ability of a noise reducing means according to a signal level detecting result. CONSTITUTION:When the detecting level of a CCD image sensor 200 by a level detecting circuit 26 is higher than a prescribed value, a coefficient control circuit 40 allows the coefficients of multipliers 30 and 34 to be 0 and stops noise reducing operation. When the detecting level is lower than the prescribed value, an operating signal from an operation detecting circuit 38 is referred and when an operating part is decided, the coefficient is allowed to be 0.5, for example, and the noise reducing operation is made effective. Thus, by turning on off the noise reduction processing according to a signal level, the rounding of the edge or the generation of the after-image can be suppressed.
Inventors:
NAKAYAMA TADAYOSHI
YOSHIMURA KATSUJI
YOSHIMURA KATSUJI
Application Number:
JP28017387A
Publication Date:
May 15, 1989
Filing Date:
November 05, 1987
Export Citation:
Assignee:
CANON KK
International Classes:
H04N5/21; H04N5/93; (IPC1-7): H04N5/21; H04N5/93
Domestic Patent References:
| JPS54157429A | 1979-12-12 |
Attorney, Agent or Firm:
Tsuneo Tanaka