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The purpose of this project lab is to introduce how to further manipulate data acquired in grayscale mode and then expand this to the realm of color. This lab is meant as a follow-up to “Video Processing Part 1: Introductory Exercise,”. This lab will implement a grayscale auto-contrast and color image manipulation.

You will complete an introductory exercise to demonstrate your familiarity with the IDK programming environment. You will then complete an introductory exercise in how to use color; and modify a C skeleton to apply simple color masks to video input from the camera.

After this lab, you should be able to effectively and efficiently manipulate grayscale images, as well as modify color images.

You may want to refer to the following TI manuals:


Having familiarized yourself with grayscale images in the previous project lab, the first part of the prelab will require you to code a function similar to the flip_invert function you have already designed, while the second part of the prelab will introduce how to use and access color images.


In this part of the prelab exercise, you will develop an algorithm to find the maximum and minimum values of a grayscale input image. Create a function that will process one row of the image at a time and find the overall minimum and maximum intensities in the image.

auto_contrast_find_extrema(in_data, min, max, col)


The NTSC camera acquires images in the color format YCbCr, where Y represents luminosity, Cb the blue component, and Cr the red component. Each image must be converted to 16-bit RGB for output on a standard color computer monitor. The function “ycbcr422pl_to_rgb565” performs this conversion. Knowing how this function converts each pixel to RGB is relatively unimportant, however, knowing the packed (5:6:5) RBG format is essential.

Before we ignore the ycbcr422pl_to_rgb565 function completely, it is useful to look at how it operates. Find the run time of the function by examining the file “ycbcr422pl_to_rgb565.c” and note that it must convert an even number of pixels at a time. If it were possible to have this function process the whole color image at in one function call, how many clock cycles would the function take? Since we are limited in the number of rows we can modify at a time, how many clock cycles should it take to process the whole image one row at a time? To demonstrate the overhead needed for this function, note how many clock cycles the function would take if it converted the whole image two pixels at a time.

RGB (5:6:5). A packed RGB pixel holds 5 bits for red, 6 bits for green, and 5 bits for blue.

Since each color is not individually addressable in the packed RGB format (e.g. bits representing red and blue are stored in the same byte), being able to modify different bits of each byte is necessary. To help clarify what bits are being set/cleared/toggled, numbers can be represented in hex format. For example, the integer 58 can be represented by “00111010” in binary or by “3A” in hex. In C, hex numbers are indicated with the prefix “0x.”

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, Ece 320 spring 2004. OpenStax CNX. Aug 24, 2004 Download for free at http://cnx.org/content/col10225/1.12
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