OpenCV gives Assertion failed error when running on GPU using OpenCL

edit

I have an "Nvidia GTX 970M" GPU & I am trying to run a face detection algorithm in c++ that runs on the GPU using OpenCL.

The function where this error occurs is :

ocl::OclCascadeClassifier::detectMultiScale()

The error I get is :

OpenCV Error: Assertion failed (localThreads[0] * localThreads[1] * localThreads[2] <= kernelWorkGroupSize) in cv::ocl::openCLVerifyKernel

I know that this problem is related to the GPU of the device but I do not know how to fix this. I have tried using OpenCV versions 2 and 3 but both give the same problem.