fourier
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Input
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An integer between 0 and 116 specifying the input image frame number. A value of 0 represents the DMA memory buffer of the video device. Values in the range of 100-116 correspond to hidden frames.
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Output
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An integer between 1 and 116 specifying the output image frame number. Values in the range of 100-116 correspond to hidden frames.
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Invert
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An enumerated integer that describes the direction of the transform:
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M_DIRECT applies the direct Fourier transform by converting the image from the spatial domain into the frequency domain.
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M_INVERSE applies the inverse Fourier transform by converting the image from the frequency domain into the spatial domain.
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FFT
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An enumerated integer that specifies if the fast Fourier transform will be enforced. Must be one of the following values:
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FALSE applies the DFT (discrete Fourier transform) algorithm as described above. If the horizontal and vertical sizes of the input image are powers of 2, the FFT (fast Fourier transform) algorithm will be applied.
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TRUE applies the Fast Fourier transform algorithm for an arbitrary image size by expanding the image horizontally and vertically to the closest width and height which are powers of 2. This is done by surrounding the image with the black margins prior to the application of the function. When the inverse transform is applied to the frequency image generated with the enforced FFT algorithm, the resulting image will retain the size of the original grayscale image.
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Default value: TRUE
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ERR_OK
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The flag set if successful.
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ERR_FAILED
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The flag set if failed.
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This set of statements applies converts a captured image into the frequency domain and then back to the spatial domain:
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GrabIm(1)
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fourier (1,2, M_DIRECT, F_FFT)
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fourier (2,3,M_INVERSE,F_FFT)
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