Modified Bat Algorithm with Local Search for Fractal Image Compression of Bitmap Images

This paper introduces a new method for IFS fractal image compression of bitmap images. The method is based on the bat algorithm, a powerful swarm intelligence method for optimization. This algorithm is modified with two additional features: a new population model based on strong elitism and new random individuals, and the inclusion of mutation operators. The modified method is also coupled with a local search heuristics for further enhancement. An illustrative example is used to analyze the performance of this approach. Our experiments on a fractal image show that the method performs very well, being able to capture the underlying structure of the original image with good visual quality. We also compared our method with other alternative approaches in the literature and found that it outperforms all of them for the given example. However, the numerical results show that there is also room for further improvement. We conclude that the method is promising and can potentially become a very useful and effective technique for fractal image compression of bitmap images.