| 摘要 |
PURPOSE:To prevent deterioration in a picture caused due to an undesired DC correction by avoiding DC correction at the fluctuation of a reference level not requiring DC correction such as reference level fluctuation (quantization error) within 1 LSB. CONSTITUTION:A low level eliminating means 5 is provided, which discriminates a difference between a reference level of a picture input signal and an objective level to be zero when the average of difference between reference level of the picture input signal after A/D conversion by an A/D converter means 2 and the objective level is a prescribed value or below. Then in the fluctuation of the reference level not requiring DC correction such that a quantizing error (error caused due to fluctuation of the DC level within two consecutive quantization values) is within 1 LSB, no DC correction is applied. Thus, the deterioration in the picture caused due to unnecessary DC correction is prevented. |
