Opening by Reconstruction Operator

Building the Cantata Workspace


To build a workspace to experiment with the opening by reconstruction operator:
  1. Choose Gaussian Noise from Generate Noise in option Input/Output. Use Width = 20, Height = 1, Mean = 50 and Variance = 20.

  2. Apply the morphological Subtraction (mmach) to subtract a constant 6 of the generated noise.

  3. Generate a 3x3 Str.El. Flat Structuring Element like the following:
               0 0 0
               1 1 1  Structuring element used
               0 0 0
    

  4. Apply the Opening by Reconstr. operator using as first input the generated noise, as second input the result of the subtraction and as third input the structuring element.

  5. Visualize the result using the Plot Display 2D in Visualization.

Exercises

  1. Implement an operator that extracts the ones and fours from the image $MMACH/viff/numbers.viff.

  2. Implement an operator that extracts the letter M from the image $MMACH/viff/M.xv

  3. Implement an operator that extracts from the image $MMACH/viff/blobs2.xv the blobs that do not desappear after an erosion by an Euclidian disk of size 10.

  4. Repeat the same exercise using as input the file $MMACH/viff/signal1.xv. Use as structuring elements for the erosion flat and non flat structural elements. What are the differences in both cases?

  5. Implement an workspace that presents as colored slide the granulommetric disbutions of the image $MMACH/viff/blobs2.xv. Use as structural elements Euclidian disks of increasing size.

  6. Inplement an operator that performs the closing of holes, without changing the contours of the holes. Use as input the file $MMACH/viff/closeholes.xv . See page close holes .

  7. Inplement an operator that performs the elimination of the objects that touch the frame. Use as input the file $MMACH/viff/blobs2.xv . See page objects in the frame off .

  8. Implement an operator that performs the change of homotopy. Use as input data the file $MMACH/viff/signal1.xv. See page change of homotopy .

  9. Build the following workspace:

  10. What could you extract from the image $MMACH/viff/keyb.xv using the operator described in the last exercise? Adjust the parameters to extract these objects.