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A description of the actual comparison process of FFT from the input image vs. image in the database. Also, construction of the database.

So, now we have an FFT of the coin. What are we going to compare it to? A pre-created database of course! Thedatabase creation steps are pretty straightforward, but there are a number of reasons for developing a streamlined approach toit.

Database creation

You could create the database manually by taking subsets of the input picture matrix and performing theunwrapping on them manually. Manual database editing might be feasible if you only had 10 coins to recognize. However,considering that the United States has minted coins for all fifty states in addition to entries for dirty coins and differentlighting conditions, you’ll probably want to simplify the process. What we did was basically take our full code and hack it off beforethe unwrapping process. The radii and centers go into a function that displays the image of the coin to the user. The user thenenters in values for the metadata associated with that image. In our case we used heads/tails, value in USD, coin name, andabbreviated coin descriptor (for debugging). We created a graphical interface in Matlab for loading images and loading and savingdatabase files.

Coin input gui

The coin input GUI we developed.

Comparison

The resulting database should contain the metadata and the precomputed FFTs of the already unwrapped coins.The code then takes each input FFT and compares it to each stored FFT. There are many different algorithms to determine the“closeness”of two FFTs.

Dot product

You can normalize each line of the FFT, and then do a vector dot product with the corresponding line in theother FFT. Then you take the average value of the resulting one-line vector. If the two FFTs are identical, they will return avalue of 1. Depending on how different they are, the number will be something between 0 and 1.

Sum of differences

You can take the FFTs, subtract them from each other, take the absolute value, and sum all of the resultingdifferences. Two identical matrices will return a value of 0. If the matrices are at all different, the sum will be greater thanzero.

In our implementation we found the dot product approach to work best, though any number of matrixcomparison algorithms could work. Once all of the FFTs have been identified, they should return the metadata to be displayed to theuser.

Questions & Answers

how can chip be made from sand
Eke Reply
are nano particles real
Missy Reply
yeah
Joseph
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
Lohitha
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
has a lot of application modern world
Kamaluddeen
yes
narayan
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Elec 301 projects fall 2006. OpenStax CNX. Sep 27, 2007 Download for free at http://cnx.org/content/col10462/1.2
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