| 摘要 |
PURPOSE:To measure a luminance distribution at real time by outputting a count signal when a luminance level of a data red-out from a memory means coincides with a set extracted luminance level, renewing the extracted luminance level and counting the number of pixels on every extracted luminance level. CONSTITUTION:An enable signal as a count signal is output to a counter 8 only when a data red-out from an image memory 4 is zero. Only when an enable signal from a gamma-RAM is input in an enable input, the counter 8 performs an increment of a counted value. Until a vertical synchronized signal is output into a clear terminal of the counter 8, the number of pixel at zero level is measured and is memorized in RAM of a control part 9. Synchronized with the vertical synchronized signal, the next gamma-curve is written in gamma-RAM 7 and only when the input luminance level is '1', it reaches high level. Then the number of pixels at level '1' is counted over one field scanning period and so forth gamma-curve is successively renewed and the number of pickcell at each gradation is counted to obtain a luminance distribution. |
