This example shows how to use
regionfill to fill a region of
interest (ROI) in an image. The example uses the
roipoly function to define the
region of interest interactively with the mouse.
regionfill smoothly interpolates
inward into the region from the pixel values on the boundary of the polygon. You can
use this function for image editing, including removal of extraneous details or
artifacts. The filling process replaces values in the region with values that blend
with the background.
Read an image into the MATLAB® workspace and display it.
I = imread('eight.tif'); imshow(I)
Create a mask image to specify the region of interest (ROI)
you want to fill. Use the
roipoly function to specify the
region interactively. Call
roipoly and move the pointer
over the image. The pointer shape changes to cross hairs . Define the ROI by clicking the mouse to
specify the vertices of a polygon. You can use the mouse to adjust the size and
position of the ROI.
mask = roipoly(I);
Double-click to finish defining the region.
roipoly creates a binary image
with the region filled with
Display the mask image.
Fill the region, using
regionfill, specifying the
image to be filled and the mask image as inputs. Display the result. Note the
image contains one less coin.
J = regionfill(I,mask); figure imshow(J)