Rotation-invariant projection-slice filter

In this paper the projection-slice SDF (PSDF) filter for rotation invariant response is discussed for pattern recognition applications. This method uses one half of a slice of the Fourier transform of the object to generate the transfer function of the filter. This is accomplished by repeating the half slice in the Fourier domain through 2 pi radians about the zero-frequency point of the Fourier plane. This filter has the advantage of always matching at least one half of a slice of the Fourier transform of any rotation of the image. An analytical discussion of the filter transfer function and impulse response are presented along with simulated correlation results for a particular target scene including decoys. These results are evaluated using the peak correlation value, peak correlation energy, and the Fisher metric for performance.