Salt & Pepper

Menu:   Processing > Filters… > Smooth > Salt & Pepper

Script:   saltPepper

Use this function to remove the salt & pepper type of noise from an image. The filter is based on the "top hat" technique that treats a pixel intensity as an elevation of a surface. Any pixel that protrudes through the "crown of the hat" which height is defined by a value of Level is considered to be noise and replaced by the mean value under the "brim of the hat". This effectively removes bright noise (salt) from the image. The inverse procedure suppresses the dark noise (pepper).

If you choose this command, the following options will become available:

Input

Displays the input image frame number. If you want to process another image, type or select the corresponding value.

Output

Displays the number of the frame in which the output image will be created. Depending on the Preferences. ImageWarp will set it either to the first available value or to the Input frame number. Type or select another value if you want the output image to be created in a different frame.

Preview

Select this check box to watch the Preview of the output image.

Size

Lets you choose the radius of the "hat" used in the function.

Level

Lets you choose the height of the "hat's crown". Any pixel that differs from the pixels under the "brim" by more than this value is considered to be noise.

Mode

Lets you choose the mode in which the function operates.

Use Reject to remove salt & pepper noise from the image

Use Select to extract salt & pepper noise from the image

Invert

Check this option to invert the operation and remove or select the dark noise. Uncheck this option to remove or select the bright noise.