Adaptive Frequency Domain Filtering For Phase Plane Correlation

A method of phase plane correlation in a digital device comprising:

• Fourier transforming first and second time domain images to create a first and second phase plane images, respectively;
• generating a window function responsive to estimated high frequency content of the first and second phase plane images;
• mixing the window function with each of the first and second phase plane images to provide first and second windowed surfaces, respectively;
• correlating the first and second windowed surfaces to form a frequency domain correlated phase plane surface;
• and
• inverse Fourier transforming the frequency domain correlated phase plane surface to provide an image plane correlation surface.

A computer program product including a computer readable medium storing program code, which when executed by a processor causes the following method to be carried out:

• Fourier transforming first and second time domain images to create a first and second phase plane images, respectively;
• generating a window function responsive to estimated high frequency content of the first and second phase plane images;
• mixing the window function with each of the first and second phase plane images to provide first and second windowed surfaces, respectively;
• correlating the first and second windowed surfaces to form a frequency domain correlated phase plane surface;
• and
• inverse Fourier transforming the frequency domain correlated phase plane surface to provide an image plane correlation surface.

A phase plane correlator comprising:

• a Fourier transform module configured to transform first and second time domain images to create a first and second phase plane images, respectively;
• a high-frequency estimator configured to estimate a high frequency content of the first and second phase plane images;
• an adaptive window function generator configured to generate a window function responsive to the high frequency content;
• a mixer configured to mix the window function with each of the first and second phase plane images to provide first and second windowed surfaces, respectively;
• a correlator configured to correlate the first and second windowed surfaces to form a frequency domain correlated phase plane surface;
• and
• an inverse Fourier transform module configured to transform the frequency domain correlated phase plane surface to provide an image plane correlation surface.