摘要 |
In the field of imaging, various components may contribute to a loss in resolution at higher spatial frequencies, both horizontally and vertically. Higher spatial frequencies may occur at the edge of an image, where there may be a large transition in the signal output between adjacent pixels. To compensate, an edge enhancement method that produces overshoots in the transitions of the video image signal is used. One of the problems with the edge enhancement method is that the noise in the input signal may not be adequately suppressed. To suppress the background noise in the video image signal while still performing the desired edge enhancement function, biasing circuitry may be used to suppress the smaller transitions in the input signal. In particular, the biasing circuitry may be placed in the signal path between the output of a first delay line and the noninverting inputs of two of the signal amplifiers. In this manner, the smaller transitions in the signal which represent background noise may be suppressed, while the edges of the video image signal are still enhanced.
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