Patent ID: 7782403
Filing Date: 2010-08-24
Classification: H04N

Abstract:
1. A noise detecting apparatus for detecting noise components involved in a video signal comprising: a first high-frequency component extractor to extract a first high-frequency component from the video signal, the first high-frequency component being involved in the video signal during each blanking interval of the video signal; a second high-frequency component extractor to extract a second high-frequency component from the video signal, the second high-frequency component being involved in the video signal in a horizontal direction for each of pixels that constitute each image carried by the video signal during each image-carrying period located between adjacent blanking intervals; a third high-frequency component extractor to extract a third high-frequency component from the video signal, the third high-frequency component being involved in the video signal in a vertical direction for each pixel, by using the video signal and a 1-line delayed video signal generated by delaying the video signal by one line in the vertical direction; a fourth high-frequency component extractor to extract a fourth high-frequency component from the video signal, the fourth high-frequency component being involved in the video signal in a time direction for each pixel, by using the video signal and a 1-frame delayed video signal generated by delaying the video signal by one frame in the time direction; a statistical processor to obtain an absolute value of each of levels of the second, the third and the fourth high-frequency components for each pixel, and obtain the number of pixels in each image per level in absolute value from a level zero to at least a predetermined level in a range from the level zero to a maximum level in absolute value for each of the second, the third and the fourth high-frequency components; and a noise detector to generate a noise detecting signal based on a level of the first high-frequency component irrespective of a result of statistical processing of the statistical processor when the level of the first high-frequency component is higher than a predetermined level whereas, when the level of the first high-frequency component is equal to or lower than the predetermined level, obtain three levels, as a first noise level, a second noise level and a third noise level for the second, the third and the fourth high-frequency components, respectively, each of the three levels having the smallest number of pixels among levels other than the level zero each having a larger number of pixels than the level zero for the corresponding high-frequency component, and generate a noise detecting signal based the lowest or the second lowest noise level among the first, the second and the third noise levels.