Spatial Filter Commands
Spatial Filters compute the luminance at a pixel location by merging the values of neighboring pixels in a particular way. The kind of filter determines the way the values are merged. The pixels sampled for computing the new value are taken from a neighborhood around or near the pixel. This type of processing is used for enhancement, of image features, suppression of noise, conversion to other value representations, and other applications. The term "spatial filter" is used to differential this type of processing in the spatial domain from filtering in the frequency domain as by using FFT's.
Spatial Filters |
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Applies a Gaussian smoothing kernel to the image. |
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Applies a rectangular smoothing kernel to the image. |
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Applies a filter of arbitrary size using weights you specify. |
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Allows you to specify the weights of a 3x3 filter kernel. This is a simplified version of the Custom Filter Kernel command. |
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Applies a "high pass" sharpening filter. The Strength parameter controls the effect. A setting of 0 performs almost no sharpening. |
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Removes isolated "speckles", or outlying pixel values. This is usually applied to RGB images to remove color channel noise. |
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Applies an unsharp mask sharpening filter. The Properties specify the blurring profile which is subtracted from the image. |
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Applies a Median filter to the image. This rejects outlying pixel values, no matter how extreme, and tends to preserve edges relatively well, but images can become "blocky" from using too large a kernel. |
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Applies a filter that mainly enhances structure that winds outward from points like the spokes of a bicycle wheel. |