Parallelisation of practical shared sampling alpha matting with OpenMP

In modern filmmaking industry, image matting has been one of the common tasks in video side effects and the necessary intermediate steps in computer vision. It pulls the foreground object from the background of an image by estimating the alpha values. However, the computational speed for matting high resolution images can be significantly slow due to its complexity and computation that is proportional to the size of unknown region. In order to improve the performance, we implement a parallel alpha matting code with OpenMP from existing sequential code for running on the multicore servers. We present and discuss the algorithm and experimentation results from the perspective of the parallel application developer. The development takes less effort, and the results show significant performance improvement of the entire program.