| 摘要 |
PROBLEM TO BE SOLVED: To apply correction to an M percentage (e.g. 90%) of an entire frequency distribution of luminance levels of an input video signal for the purpose of enhancing the resolution of a video image. SOLUTION: The video signal correction circuit is provided with a histogram detection section 32 that detects a frequency distribution of luminance levels of an input video signal, a luminance level detection section 34 that detects luminance levels a1, a2 at both ends of the distribution area sharing an M percentage (0<M<100) of the entire frequency distribution on the basis of a detected number of frequencies of luminance levels, a ROM 36 that stores correction data in advance corresponding to an input output conversion characteristic curve where a gradient between the luminance levels a1 and a2 is a maximum with respect to a plurality of sets of the luminance levels a1 and a2 and from which corresponding correction data are read by using the detected luminance levels a1 and a2 for addresses, and a picture quality correction section 16 that corrects the input video signal on the basis of the read correction data and provides an output of the result. The video signal correction circuit corrects the input video signal according to the input output conversion characteristic curve where a gradient between the luminance levels a1 and a2 is a maximum.
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