Accelerated method for the optimization of quadratic image filter

Quadratic image filter involves the second-order multiplications of an input image mask in addition to linear terms, and determining the weights of the quadratic filter using optimization methods requires intense computational power due to the cost of the resulting fitness function. A graphics processing unit (GPU)-based algorithm is proposed to determine quadratic image filter weights using genetic algorithms and particle swarm optimization methods. Since the most time consuming part of determining the mask weights using heuristic algorithms is the fitness computation process, the fitness computation process is designed to work on the GPU, and a significant acceleration is achieved. For this purpose, different designs such as direct method and population-based method have been developed within the GPU to minimize training time. According to experimental results, the proposed methods provide significant accelerations over sequential implementation. The first method computes the fitness function for each population member separately, and it produces about 43 times acceleration over the sequential implementation. The second method developed is based on the complete evaluation of the population, and it produces about 151 times acceleration over the sequential implementation. (C) 2019 SPIE and IS&