CMOS sensors of digital color cameras sometimes produce ``bad pixels'' that appear as positive impulse noise in captured images. Because the occurrence and the magnitudes of the impulses vary over time, an algorithm is needed to deal with these defects when and where they occur. This paper describes the demands on the noise removal method, details various algorithms that were implemented to address this problem, and finally provides some performance results. The most effective algorithms consist of separate routines for impulse detection and replacement, i.e. the approximation of detected defects. In addition to implementations of some common methods, modified to work with the color filter array, a new method was developed for this application. The proposed algorithm adapts the detection sensitivity to the current detail level of the image.
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