Merges an image's magnitude and phase from separate inputs into a packed format frequency domain image. The output array has 2*(NC - 1) columns for inputs with NC columns. Thus FourierMergeImg is used to create arrays compatible for use with the InverseFFTImg module from outputs of FourierMagnitudeImg and FourierPhaseImg. The input must be a frequency domain image in the reduced packed format produced by the FourierMagnitudeImg or FourierPhaseImg modules. The Fourier transformation and the cross correlation are discussed in:

Digital Image Processing, Gonzales, R.C., Wintz, P., Addison Wesley, Second Edition, 1987, pp 61--137.

Because the FFT format is packed, it is not possible to tell what the x size of the original image was to an accuracy of better than one sample. For this reason, the parity of the x size, either even or odd, must be properly set on the module for numerically correct results. If this value is in error, the resulting image will be the wrong size, although it will probably look visually correct.


Port: First Img In
Type: Lattice
Constraints: 1..3-D
Magnitude image (compressed).

Port: Second Img In
Type: Lattice
Constraints: 1..3-D
Phase image (compressed).


Port: X Parity
Type: Option Menu
Menu Item: Odd
Menu Item: Even
Parity of the x size of the original image (even or odd).


Port: Img Out
Type: Lattice
Constraints: 1..3-D
Merged frequency domain image.



ForwardFFTImg, InverseFFTImg, FourierMagnitudeImg, FourierPhaseImg.
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© The Numerical Algorithms Group Ltd, Oxford UK. 2000