| 摘要 |
PROBLEM TO BE SOLVED: To make a dark scene picture easy to see without improving contrast. SOLUTION: A composite video signal from an input terminal 1 is supplied to a separation circuit 2 and separated to a luminance signal and two color difference signal. This separated luminance signal is supplied to dynamic gamma circuit 5. In this dynamic gamma circuit 5, a characteristic curve of gamma compensation between an input and an output is changed in accordance with a control signal from a control circuit 11 so that an intermediate signal level is strengthened from a nearly straight line. These gamma compensated luminance signal and two color difference signal are converted to three primary colors by a converting circuit 6, and supplied to a display means 8 such as a plasma display and the like through A/D conversion circuits 7R, 7G, 7B, respectively. Also, a luminance signal from the separation circuit 2 is supplied to an integration circuit 10 through a comparing circuit 9, a signal from this integration circuit 10 is supplied to the control circuit 11, and a control signal having magnitude in accordance with an average luminance level is formed. |
