Description
Creates a new FFT data set whose size is a multiple or a fraction of the original.
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Return Type
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A McImage object.
A new complex FFT data IMcImage.
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Syntax
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object.ScaleFFT (Ratio, [vFFTImage], [Flags])
The ScaleFFT Method syntax has these parts: |
| object | An expression evaluating to an object of type McFFT. | | Ratio | Required. A Long value. Scaling ratio.Positive number: scale up.Negative number: scale down.
| | vFFTImage | Optional. A Variant value. Optional input FFT data IMcImage.
| | Flags | Optional. A mcImageCreateFlags enumeration, as described in settings. Image creation flags
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Settings 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
Image scaling using sinusoidal interpolation can be achieved by first obtaining the Fourier transform of the image, padding or clipping the Fourier data, and inverse transforming the data back into an image. For example, a 256 x 256 FFT data set will be made into a 512 x 512 set by padding it with zeros all around. Performing an inverse Fourier transform on the new set will produce an image that is twice the size of the original image. The sinusoidal interpolation used in the oversampling is of higher quality than a simple linear interpolation.
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ScaleFFT Method
