| 摘要 |
FIELD: graphic data indication means. ^ SUBSTANCE: device has block for calculation of average brightness, block for data conversion and block for calculation of output video data, while block for average brightness calculations determines average brightness level, average image level for images with length n frames on basis of input video data X(X>=0) in coordinate system X-Y, conversion block determines data Xc and Yc with appropriate central point on basis of average image level, and block for calculation of output video data determines output video data Y(Y>=0) gathered after adjustment of contrast level in accordance to formula Y=A.X+Xc.(1-A), where A>0 is steepness, set by variable for adjusting contrast, as a result of which, when A increases and contrast also increases, brightness increase at low level is suppressed for contrast adjustment in accordance to average image level for images with length of certain number of frames. ^ EFFECT: higher efficiency. ^ 2 cl, 8 dwg |
