BIOIMAGE SEGMENTATION USING LabVIEW DONE BY INTERNAL GUIDE S.PONKULALI(087023) A.UMARANI T.S.UVASRE(087119) ASP/EIE
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BIOIMAGE SEGMENTATION
USING LabVIEW
DONE BY INTERNAL GUIDE
S.PONKULALI(087023) A.UMARANI
T.S.UVASRE(087119) ASP/EIE
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CONTENT OF PRESENTATION
Work Objective
Introduction
Block Diagram
Edges of Image Edge Detection
Methods of Edge Detection
Conclusion
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WORK OBJECTIVE
To subdivide an image into itscomponent or regions or object.
It should stop when the objects of
interest in an application have beenisolated.
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INTRODUCTION
• The purpose of image segmentation is to
partition an image into meaningful regions
with respect to a particular application.• The segmentation is based on
measurements taken from the image and
might be greylevel , colour , texture, depth or motion.
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BLOCK DIAGRAM
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EDGES IN IMAGE
An edges that correspond to object
boundaries.
Image pixels brightness changes abruptly.
The image function behavior in a
neighborhood of the pixel
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EDGE DETECTION
Edge detection is the approach used most
frequently for segmenting images based
on abrupt(local) changes in intensity.
Edge models are classified according totheir intensity profiles
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METHODS OF EDGE
DETECTION
First Order Derivative / Gradient Methods
◦ Roberts Operator
◦ Sobel Operator
◦ Prewitt Operator
Second Order Derivative
◦ Laplacian operator
◦ Differential operator
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Gray-Level Transition
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THE FIRST DERIVATIVE
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GRADIENT OPERATORS
The gradient of the image I(x,y) at
location(x,y),is the vector:
The magnitude of the gradient:
The direction of the gradient vector:
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CALCULATING THE GRADIENT
For each pixel the
gradient is calculated,
based on a 3x3
neighborhood around this
pixel. z1 z2 z3
z4 z5 z6
z7 z8 z9
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ROBERTS OPERATOR
Mark edge point only
Mostly suitable for binary images
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PREWITT OPERATOR
Looks for edges in both horizontal andvertical directions, then combine theinformation into a single metric.
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SOBEL OPERATOR
Similar to the Prewitt, with different mask coefficients:
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LAPLACIAN OPERATOR
Edge magnitude is approximated in digitalimages by a convolution sum.
The sign of the result (+ or -) from two
adjacent pixels provide edge orientationand tells us which side of edge brighter
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LAPLACIAN OPERATOR (Cont.)
Masks for 4 and 8 neighborhoods
Mask with stressed significance of the
central pixel or its neighborhood
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ORIGINAL IMAGE
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RESULTS OBTAINED
ROBERTS EDGE DETECTOR
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PREWITT OPERATOR
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SOBEL OPERATOR
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LAPLACIAN OPERATOR