Improved median filter using conditional technique and its hardware implementation

Median filtering is a very important preprocessing operation in many computer vision applications. This paper presents an improved median filtering algorithm, which uses a simple conditional technique. The presented algorithm shows significantly better performance than standard median filter and is suitable for hardware implementation. To illustrate the performance of the algorithm, the results of comparison with the standard median filter and resulting images for both algorithms are given as illustration. A hardware implementation of the conditional median filter is also presented, that extends the applicability of this algorithm in the area of real time image processing. The designed hardware filter enables achieving of frame rates of hundreds of frames per second for a 1024×1024, 8-bit gray-scale picture.

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