Description
Applies forward Fast Fourier Transform to a monochrome image.
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Return Type
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A McImage object.
A new IMcImage whose meaning depends on Output.
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Syntax
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object.Forward ([Output], [Flags], [vSourceImg])
The Forward Method syntax has these parts: |
| object | An expression evaluating to an object of type McFFT. | | Output | Optional. A mcFFTForwardOutput enumeration, as described in settings. mcFFTForwardOutput : Output type.
| | Flags | Optional. A mcImageCreateFlags enumeration, as described in settings. A combination of mcImageCreateFlags used in creation of the output image
| | vSourceImg | Optional. A Variant value. Optional source IMcImage.
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Settings The settings for Output are:
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 | mcfoRealImaginary | 0 |
FFT.Forward returns real and imaginary parts combined in one image.
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| mcfoPolar | 1 |
FFT.Forward returns the amplitude and phase of the spectrum combined in one image.
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| mcfoRealImaginaryDouble | 2 |
These are the same as the above, except that the result will be double
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| mcfoPolarDouble | 3 |
will be double instead of single precision floating point
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The settings for Flags are:
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| mcicfDefault | 0 | |
| mcicfContiguous | 1 |
If set, frames are allocated contiguously, and you cannot add to the FrameCount at a later time.
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| mcicfNoInit | 2 |
Default is to initialize to 0 (black), this flag suppresses initialization.
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| mcicfNoAddToCollection | 4 |
If set, the image is created, but not added to the collection (see Notes).
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| mcicfNotVisible | 8 |
If set, the image is created, possibly added to collection (see above), but not made visible.
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| mcipfNoImportProperties | 8388608 |
Suppress ImportProperties for functions creating an image from another.
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Remarks
The dimensions of the image instance must be powers of two (see Padding); otherwise the function transforms the closest smaller/larger image of such dimensions depending on the value of Padding.
If Output is mcfoAmplitude, the returned image is the amplitude of the spectrum, linked to a hiden phase image. If Output is mcfoPhase, the returned image is the phase of the spectrum, linked to a hiden amplitude image. These links are used by the methods needing both components, to locate the missing one.
If Output is mcfoRealImaginary, the width of the returned image is twice the width of the image instance, since each FFT pixel contains two elements (real and imaginary). The DC component of the FFT spectrum is located on the center of the image. FFT data are stored in images for convenience; these are not, however, displayable images.
This function is applicable to monochrome images only.
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Forward Method
