ADAPTIVE CLIPPING PREVENTION FOR PICTURE SHARPNESS ENHANCEMENT

摘要

A contrast control and clipping device is configured to determine a maximum range of enhancement that may be applied to each pixel for picture sharpness enhancement. This maximum range is used to limit the enhancement that is determined by the conventional convolution kernel and gain control modules. Preferably, the maximum range is independent of the determined convolution value, thereby minimizing the bandwidth requirements among the modules used for picture sharpness enhancement. The reduced bandwidth requirement allows for an efficient partitioning of tasks between hardware and software embodiments, and eases the overall system design task. In a multi-media application, the amount of data that is transferred between the processor and sub-components is substantially reduced, and the efficient partitioning facilitates parallel processing. The maximum range of enhancement is determined based on the pixel values in the current field, using a computationally simple algorithm, thereby minimizing anomalies caused by temporal dependencies among the modules that are used for picture sharpness enhancement. Additionally, the sharpness enhancement is dynamically adjusted based on overall picture-level characteristics, including the average enhancement range, overall noise measures, and so on.