| 摘要 |
Techniques for enhancing edges in video signals while reducing the amounts of undershoots and overshoots. A video signal is processed to generate a first signal indicative of detected edges in the video signal. The first signal can be generated by lowpass filtering the video signal to generate a lowpass signal and subtracting the lowpass signal from a luminance signal that has been extracted from the video signal. The first signal is then processed with a "non-linear" transfer function to generate a second signal having enhanced edges. The second signal is used as the correction or enhancement signal, and is added to the lowpass signal to provide an output signal having enhanced edges with reduced or minimal amounts of undershoots and overshoots. The second signal has one or more of the following characteristics: (1) it is dynamically generated based on characteristics of the detected edges in the video signal; (2) it provides varying amounts of enhancement across the detected edges in the video signal; (3) it provides higher amounts of enhancement near the center of the detected edges and smaller amounts of enhancement away from the center; and (4) it provides an amount of enhancement that is dependent on the slope of the detected edges.
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