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Implementation of the algorithm

The algorithm is implemented by the code in a conventional for loop, which begins in Listing 4 .

Listing 4 . Beginning of the for loop.
for(int cnt = 0;cnt<pixels.length;cnt++){ pixel = pixels[cnt];green = pixel.getGreen();blue = pixel.getBlue();

The loop iterates through the array of Pixel data, modifying the colors in one pixel during each iteration.

The length property of the array object

Every array object in Java contains a length property that contains the number of elements in the array. The value of this property is used in theconditional clause in the for loop in Listing 4 to establish when the end of the array has been reached in order to terminate the loop.

Get reference to the next Pixel object

The first statement inside the for loop in Listing 4 gets a reference to a Pixel object from the next array element. That reference is stored in the local variable of type Pixel named pixel that was declared in Listing 3 .

Get the red and green color values for the current pixel

Having gotten a reference to the Pixel object, the next statement calls the getGreen method on that reference to get and save the value of the green color component in the current pixel.

Similarly, the statement following that one gets and saves the value of the blue color component in the current pixel.

Both values are returned as type int , and can range in value from 0 up to and including 255.

Objective is to scale the green and blue color values

Recall that the objective is to scale the green and blue color values on a column by column basis, going from left to right across the image shown in Figure 1 in order to produce the output image shown in Figure 2 .

Organization of the pixel data

The pixel data is stored in the array on a row by row basis. In other words, the first width elements contain references to pixels in the first row of pixels going from left to right across the screen. The next width elements contain references to pixels in the second row of pixels, etc.

Compute the column number and scale factors

Listing 5 uses the modulus operator to compute the column number for each Pixel object.

Listing 5 . Compute the column number and scale factors.
//Compute the column number and use it to compute // the scale factor.int col = cnt%width;greenScale = (double)(width - col)/width; blueScale = (double)(col)/width;

An exercise for the student

Knowing the column number in which the pixel is located, the next step is to compute the green and blue scale factors necessary to satisfy the algorithm.

I will leave it as an exercise for the student to think about how the expressions contained in the last two statements in Listing 5 cause the two scale factors to vary linearly from left to right across the image in accordance with the requirements of the algorithm. (Think about the equation of a straight line from your high school math classes.)

Apply the scale factors

The Pixel class contains methods named setRed , setGreen , and setBlue that can be called to set the color values for the pixel represented by a Pixel object.

Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
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
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
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
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
how did you get the value of 2000N.What calculations are needed to arrive at it
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Source:  OpenStax, Object-oriented programming (oop) with java. OpenStax CNX. Jun 29, 2016 Download for free at https://legacy.cnx.org/content/col11441/1.201
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