Pruning.in.Image.processing

Advanced topic in Image Processing

PruningBy

Qaisar Ayub

Sheikh Qaisar Ayub , Sulma Rashid

[email protected]

PruningWhat ?A post processing Operation on images

Thinning and skeltonization algorithms tends to leave the parasitic

components

Parasitic Components

Pruning

PruningProblemOur task is to recognize the hand written characters

Solution

Find the skeleton of each character

During the process of skeleton some of the parasitic

components associated in each character

These parasitic components derived due to the non

uniformalities in the strokes composing the character

PruningParasitic

Q

Observe Parasitic Components

Pruning

Achievements

1. What is pruning

2. Parasitic Components

PruningTo understand the pruning algorithm we take an example of

recognizing the handwritten character ‘a’

After applying the skeltionization algorithm we get the following structure

Pruning

This is what we are interested to remove

PruningAlgorithm

Step-01

Suppress the parasitic components by eliminating the end

points

By applying the thinning algorithm on the image we can get

endpoints

Mathematically the thinning algorithm can be written as

X1 = A {B}

PruningAlgorithm

Step-01

X1 = A {B}

B := Structuring element

{ } := Represent the iteration

A := Input Image

:= Hit or Miss Translation

PruningAlgorithm

Step-01

X1 = A {B}

Structuring element {B} = B1 B2 B3 B4 B5 B6 B7 B8

B1

B2

B3

B4

PruningAlgorithm

Step-01

X1 = A {B}

Structuring element {B} = B5 B6 B7 B8

B5 :=

B6:=

B7:=

B8:=

Pruning

Pruning

No match found Row 01

Pruning

Pruning

After applying thinning 3 times we get X1

X1=

Pruning

Achievements

End Point Removing process has

been completed

PruningAlgorithm

Step-02

Restore the character to its original Form by removing

parasitic branches

Solution

Form a set X2 by which contains all end point in X1

Following equation is used to achieve this

PruningAlgorithm

Step-02

X1 B1

X1 B2

PruningAlgorithm

Step-02

X1 B3

X1 B4

PruningAlgorithm

Step-02

X1 B5

X1 B6

PruningAlgorithm

Step-02

X1 B7

X1 B8

Pruning

X2=

Pruning

Achievements

End point have been found from X1

PruningAlgorithm

Step-03

H= Structuring Element

X2=

Pruning

Pruning

Achievements

Dilation process at end point have

been completed

PruningAlgorithm

Step-03 Continue…

∩ A

∩

Pruning

∩ A

X3=

Pruning

Achievements

PruningAlgorithm

Step-04

X4 = X1 U X3

Thanks

Pruning.in.Image.processing

Documents

Transcript of Pruning.in.Image.processing