is an option for various image and signal processing functions that specifies on which regions they should operate.


  • Masking is also known as region of interest (ROI) or volume of interest (VOI).
  • The typical settings include:
  • Allentire object
    Automaticautomatic selection
    {pos1,pos2,}specific positions
    imagegrayscale or binary version of image
    regionany ConstantRegionQ
    graphicsuse positive raster values
    arrayuse positive values in array
  • When the region of interest is specified as an array or image, it is taken to be centered on the image to be processed.


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Basic Examples  (2)

Apply a function to image pixels in a specified region of interest:

Compute image measurements only on a specified region of interest:

Scope  (1)

Perform color negation to the whole image:

This is equivalent to Masking->All:

Use a region as the mask:

Use a binary image as the mask:

Use a grayscale image as the mask:

Applications  (1)

Separate the foreground from the background:

Apply a function to the background:

Introduced in 2010
Updated in 2012