Patent ID: 6950114
Filing Date: 2005-09-27
Classification: H04N

Abstract:
1. A luminance level compensating apparatus comprising: a first masking device for passing only a luminance signal corresponding to a pixel in a first detection range in the vertical direction of an image which is indicated by an input luminance signal; a second masking device for passing only a luminance signal corresponding to a pixel in a second detection range in the vertical direction of the image which is indicated by said input luminance signal, wherein the first detection range corresponds to a first predetermined image area and the second detection range corresponds to a second predetermined image area, which is not equal to the first predetermined image area; a first histogram memory device for detecting and storing a first frequency data for each luminance level of the luminance signal output from said first masking device for each predetermined period; a second histogram memory device for detecting and storing a second frequency data for each luminance level of the luminance signal output from said second masking device for each predetermined period; a multiplying device for multiplying the first frequency data stored in said first histogram memory device by a coefficient; a selecting device for comparing the first frequency data output from said multiplying device with the second frequency data stored in said second histogram memory device and for outputting frequency data having a smaller value; and a compensating device for compensating the luminance level of said input luminance signal based on the outputted frequency data.