Patent ID: 7286179
Filing Date: 2007-10-23
Classification: H04N

Abstract:
1. A defective pixel filter comprising: a first comparator circuit receiving as input a first pixel value and a second pixel value and outputting a valid logic signal to a first input of an AND circuit and to a first inverter when the first pixel value is greater than the second pixel value; a first difference calculator receiving as input said first pixel value and said second pixel value and outputting to a first input of a second comparator circuit a first difference value corresponding to the difference between said first and second pixel values; said second comparator circuit also receiving as input a threshold value and outputting a valid logic signal to a first input of an OR circuit when the first difference value is less than or equal to said threshold value; a third comparator circuit receiving as input said second pixel value and a third pixel value and outputting a valid logic signal to a second input of said first AND circuit and to a second inverter when the second pixel value is greater than the third pixel value; and a second difference calculator receiving as input said second pixel value and said third pixel value and outputting a second difference value corresponding to the difference between said second and third pixel values to a first input of a fourth comparator circuit; said fourth comparator circuit also receiving as input a threshold value and outputting a valid logic signal to a third input of said OR circuit when the second difference value is less than or equal to said threshold value; and a second AND circuit coupled to said first and second inverters and having an output coupled to a fourth input of said OR circuit.