title: How to get the real and imaginary parts of a gabor kernel matrix in OpenCV
body: <p>A OpenCV beginner and bad math.
  My job is to apply the Gabor filter to a normalized image. And I only know that OpenCV has a <code>getGaborKernel</code> function, and i want to know the return Matrix of this function is the real part or the imaginary part of the kernel.
  If I can't use this function, then how can I generate those kernel?
  Using Java API, but C++ code is fine.</p>