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Example:

  • int black = 0x00; // black = 0
  • int foo_h = 0xF0; // foo_h = 240
  • int foo_l = 0x0D; // foo_l = 13

Another thing to note is that each pixel requires two bytes of memory, requiring two memory access operations to alter each pixel. Also NOTE that in a row of input color data, the indexing starts at 1. Thus RGB[1] contains red/green data and then RGB[2]contains the green/blue data – both for the first pixel.

What is the packed RGB value for the highest intensity green? What is the value of the first addressable byte of this ‘hi-green’ pixel? What is the value of the second byte?

Now, say you are given the declaration of a pixel as follows:

int pixel;

Write a simple (one line is sufficient) section of code to add a blue tint to a pixel. Do the same for adding a red tint, and for a green tint (may require more than one line).Use the and (represented by an ampersand) operator to apply a mask.

Implementation

The first part of this lab will require you to write a function to perform auto-contrasting. You should use your function from prelab 2.1 to obtain the maximum and minimum values of the image, and then create another function to do the appropriate scaling.

The second part of this lab will involve implementing some simple, and hopefully cool, color effects.

Grayscale

Use the function you designed in prelab 2.1 to create an algorithm to auto-contrast the image. Auto-contrast is accomplished by scaling the pixel value from the min-to-max range to the full range. This effect is seen below:

(left) Frequency of a grayscale image with pixel intensities ranging in value from 32 to 128, and (right) Frequency of the same grayscale image after performing an auto-contrast.

Recall from “Introduction to the IDK” that the DSP has a floating point unit; the DSP will perform floating point instructions much faster than integer division, quare-root, etc.

Example:

  • int opposite, adjacent;
  • float tan;
  • tan = ((float) opposite) / ((float) adjacent);

This function should be called similarly to the flip_invert function in the previous lab. Once you have implemented your function, look for ways to optimize it. Notice that you must loop through the image twice: once to find the minimum and maximum values, and then again to apply the scaling. (Hint: the function dstr_rewind rewinds the image buffer).

Use the same core files for this part of the lab as were used in the previous lab. You may simply make a copy of the previous lab’s folder and develop the necessary code from there.

Color

In this part of the lab, you will use the concepts from the prelab to implement certain effects.

Copy the directory “V:\ece320\projects\colorcool” to your W: drive.

We want to use a certain area of the screen as a "control surface". For example, the fingers held up on a hand placed within that area can be used as a parameter, to control the image on the screen. Specifically, we will use the total brightness of this control surface to control the color tint of the screen.

You are given a shell program which takes in a color input frame in YcbCr format and converts it to RGB. You will modify this shell to

  • 1. Calculate the total brightness
  • 2. Calculate the tint for each color component R, G and B.
  • 3. Apply the tint to the image

Questions & Answers

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
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
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
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
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
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
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, Ece 320 spring 2004. OpenStax CNX. Aug 24, 2004 Download for free at http://cnx.org/content/col10225/1.12
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