Image enhancement filters – UVP Doc-It Life Science User Manual
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Using Image Filters
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Flip Vertically
This image filter mirror-images an image, top for bottom. Unlike most image filters, it does not degrade
the image and may be used repeatedly with no ill effect. Two uses of the filter will return the image to its
starting orientation.
Click onto Flip vertically from the Filters plug-in or use the Image > Filters > Flip vertically command.
Image Enhancement Filters
Image enhancement tools allow users to highlight important features and remove unwanted signal in the
image.
Remove Noise
This filter removes periodic (patterned) noise from an image. Patterned noise is removed by creating a
frequency-space mapping (Fourier transform) of an image and removing frequency spikes away from the
graph's origin.
There are two issues to be aware of with noise removal. First, if the image has actual (desired) pattern
information, the operation will not be able tell these from noise and it will remove them. Second, the
mathematics of the operation can cause some edges pixels to be identified as patterns, resulting in
blurring on some images.
Click onto Remove noise from the Filters plug-in or use the Image > Filters > Remove noise
command. Removing noise a large image may take ten or fifteen seconds.
Despeckle
This filter removes single-pixel flaws (called artifacts) from an image. For many reasons, the image
capturing process and hardware might misread isolated individual pixels as either white or black. The
Despeckle filter mathematically identifies and removes these "loner" pixels.
There are two issues to be aware of with the Despeckle filter. First, if the image has actual (desired)
single-pixel bright or dark areas, the operation will not be able tell these from artifacts and it will remove
them. Second, the mathematics of the operation can cause some edge pixels to be identified as
"speckles," resulting in slight blurring on some images.
Click onto Despeckle from the Filters plug-in or use the Image > Filters > Despeckle
command. Despeckling a large image may take a few seconds.
Sharpen
This filter enhances edges in an image, making them more visible. It is easier to see fine detail after an
image has been sharpened.