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The module covers the techniques and challenges associated with image acquisition


High quality images are a necessary component of any object recognition system. Factors such as lighting,background, and motion all contribute to the instability of any imaging environment. As soon as one of these factors changes, evenslightly, the ability for a computer to detect an object from an image may be severely hampered. However, pursuing a controlledenvironment is most likely a dead-end. In the context of real world object recognition, environment is often not controlled andsometimes is rapidly changing. For this project, though, we need to create a special imaging environment to minimize the complexity ofimage acquisition.


We need to create a semi-ideal environment in which to image the coins. The apparatus is composed of a tough black plastic milk crate, a semi-reflectivewhite foam board piece, and a matte black foam board piece for the imaging base. It is important to create a contained system becauseit allows us to remove, to the best of our ability, the environment variable. Once the box is constructed, we need to determine thebest way to light the coins. Even and consistent lighting is a necessity. To achieve this we need to sufficiently diffuse thelighting as to avoid specular highlighting. We hang the lights from the top of the box at an angle to the outside edges of the box.Doing so allows the incident light to “bounced” off the walls of the box thus diffusing the rays. However, we you will find this to beinsufficient. It became apparent that using cloth, or even a milk jug, is a more effective approach. You can use any materials you have lying around. For example, if you cut out small squares of a white undershirt and strategically place them between the lights and the coins, you can achieve a sufficient level of light diffusion. The process may be time intensive but keep tweaking until you find agreeable results.

Image acquisition apparatus

A picture of the hardware apparatus used to image the coins.


The camera, a Canon PowerShot S410, suspended from the top of the box, is able to image the coins from a fixed distance and locationfor each take. Because we must image multiple coins at the same time, the camera cannot adjust its shutter speed based on thebrightness of just one coin. Thus, if there are specular highlights on one coin, and not on another, our image would reflect this. Disparities among the coins, due to lighting, are unacceptable. This provides the motivation fortaking great pains to place the lights in a manner provides even lighting conditions.

While we used a Canon camera, any camera should be sufficient as long as it has the ability to take quality images.

Image capture software

We need to be able to quickly capture images without any human intervention. Minute changes in the angle or location of the camera might interfere with the settings in our software. It would also remove the consistency in images we obtain by fixing the camera. We can accomplish this easily using Canon’s Remote Capture software on the computer. With the software, you have controlover exposure, white balance, and ISO levels. On the subject of quality: it needs to be mentioned that any JPEGcompression could result in less reliable results. Because the algorithms used for this project are dependent on recognizingthe unique details of each coin, throwing out any of that information could have drastic effects.

The Canon Remote Capture software comes standard with many Canon cameras. It is available on the Canon website free of charge.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
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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