Color-balance demo with GPU computing

Use GPU in MATLAB to perform white-balance operation to input image.

This demo shows how to identify bottlenecks in code that is run on a CPU using the MATLAB Profiler.
The computations forming the bottleneck in this example are then executed on the system's GPU using the gpuArray() command and the interface to CUDA kernels.

Code to compare the calculations from the CPU and from the GPU is also provided.