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Scale-invariant feature results

Sift results on image of rice

Rice SIFT
The curves are well detected but horizontal and vertical lines are lost.

Sift results on bibo bear

A dog sitting on a bed
The words BIBO can be seen on the bear's chest.

Sift results on president leebron

A dog sitting on a bed
It is evident that it is the image of a person.

Although SIFT is extremely useful, it cannot easily find vertical or horizontal lines because they are not considered feature points. Since our image templates were made up of almost all straight lines, we had a significant issue. Due to time constraints we chose to implement the edge functions in MatLab. Instead of passing the results of SIFT into the Hough Transform and Moment of Inertia we passed the results of the edge functions in MatLab.

Results of matlab functions

Results of passing a test image into matlab edge functions

A dog sitting on a bed

Clearly the edge results from matlab are much more suited to our type of test images.

Hough transform results

A dog sitting on a bed
The Hough Transform of the template image.

A dog sitting on a bed

A dog sitting on a bed

Even with noise same peaks are found.

A dog sitting on a bed

A dog sitting on a bed
Same peaks are found with noise.

A dog sitting on a bed

A dog sitting on a bed

With this amount of noise the peaks are still found. As long as the noise does not interfere with the edges the peaks will always be found. However, if the edges are lost then the Hough Peaks will be incorrect.

Moment of inertia results

Description of steps in demo

  1. Read in the image as a matrix of type ‘double’ and turn it into a logical array (im2bw function)
  2. Using bwboundaries functions, find all connected boundaries (default is 4-connectedness of pixel)
  3. Iterate through all closed boundaries and mask all pixels within boundary to be 1 and 0 outside the boundary
  4. Find the moment of inertia of the masked images which is normalized by the square total number of pixels

A dog sitting on a bed

Moment of inertia method on simple image

A dog sitting on a bed

Moment of Inertia Method works perfectly on a test image without overlaps where the shapes are significantly different.

However, bwboundaries returns closed boundaries which would create problems when you have intersection of lines.

Moment of inertia method on image with overlaps

A dog sitting on a bed

We can clearly see from the previous images that the function now detects 4 objects instead of the three that we are interested in, shown below as the two larger squares traced out by red outline and the smaller one filled by the color green.

A dog sitting on a bed

Moment of inertia method on image with similar shapes

A dog sitting on a bed

In the above image, objects in the top right and top left corners of the subplots differ in moment of inertia by 0.703%, in spite of having drastically different shapes. However, we note that such algorithm would only produce false positive.

Questions & Answers

a diagram of an adult mosquito
mubarak Reply
what are white blood cells
Mlungisi Reply
white blood cell is part of the immune system. that help fight the infection.
MG
what about tissue celss
Mlungisi
Cells with a similar function, form a tissue. For example the nervous tissue is composed by cells:neurons and glia cells. Muscle tissue, is composed by different cells.
Anastasiya
I need further explanation coz celewi anything guys,,,
Calvin Reply
hey guys
Isala
on what?
Anastasiya
is air homogenous or hetrogenous
damiane Reply
homogenous
Kevin
why saying homogenous?
Isala
explain if oxygen is necessary for photosynthesis
Allice Reply
explain if oxygen is necessary for photosynthesis
Allice Reply
Yes, the plant does need oxygen. The plant uses oxygen, water, light, and produced food. The plant use process called photosynthesis.
MG
By using the energy of sunlight, plants convert carbon dioxide and water into carbohydrates and oxygen by photosynthesis. This happens during the day and sunlight is needed.
NOBLE
no. it s a product of the process
Anastasiya
yet still is it needed?
NOBLE
no. The reaction is: 6CO2+6H20+ solar energy =C6H12O6(glucose)+602. The plant requires Carbon dioxyde, light, and water Only, and produces glucose and oxygen( which is a waste).
Anastasiya
what was the question
NOBLE Reply
joining
Godfrey
the specific one
NOBLE
the study of non and living organism is called.
Godfrey
Is call biology
Alohan
yeah
NOBLE
yes
Usher
what Is ecology
Musonda Reply
what is a cell
Emmanuel Reply
A cell is a basic structure and functional unit of life
Ndongya
what is biolgy
Hawwi Reply
is the study of living and non living organisms
Ahmed
may u draw the female organ
MARTIN Reply
i dont understand
Asal
:/
Asal
me too
DAVID
anabolism and catabolism
Sani Reply
Anabolism refers to the process in methabolism in which complex molecules are formed "built" and requires energy to happen. Catabolism is the opposite process: complex molecules are deconstructed releasing energy, such as during glicolysis.
Anastasiya
Explain briefly independent assortment gene .
Otu Reply
hi
Amargo
hi I'm Anatalia
Joy
what do you mean by pituitary gland
Digambar
draw and lable the cell
Ameh Reply
why homones are destroyed soon after completing their role
Nyirenda Reply
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Source:  OpenStax, Elec 301 projects fall 2014. OpenStax CNX. Jan 09, 2015 Download for free at http://legacy.cnx.org/content/col11734/1.2
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