Title:
IMAGE PICKUP DEVICE
Document Type and Number:
Japanese Patent JPS62226772
Kind Code:
A
Abstract:
PURPOSE:To preclude the possibility of deterioration in the picture quality of a reproduced picture due to gamma correction by detecting the distribution of lightness of a picked-up picture and applying change control to the gamma correction quantity in the unit of picture elements in response to the distribution of the lightness. CONSTITUTION:A lightness detection circuit 16 discriminates the area and lightness of a light picture and the area and lightnes of a dark picture based on a frame memory data stored in a frame memory 15, designates selectively an optimum gamma correction curve to the light picture and sets the result to the 1st conversion circuit 21A. Further, the circuit 16 designates the gamma correction curve optimum to the gamma correction to the dark picture and sets the result to the 2nd conversion circuit 21B. Thus, a reproduced picture is obtained, where noisy impression is not given by the share of noise signal component not emphasized as the picture corresponding to the dark picture.
Inventors:
KONDOU NORIAKI
Application Number:
JP6938486A
Publication Date:
October 05, 1987
Filing Date:
March 27, 1986
Export Citation:
Assignee:
SONY CORP
International Classes:
H04N5/202; (IPC1-7): H04N5/202
Attorney, Agent or Firm:
Kei Tanabe