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Introduction

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:

Prelab

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.

Grayscale

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)

Color

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

what is the coefficient of -4×
Mehri Reply
-1
Shedrak
the operation * is x * y =x + y/ 1+(x × y) show if the operation is commutative if x × y is not equal to -1
Alfred Reply
An investment account was opened with an initial deposit of $9,600 and earns 7.4% interest, compounded continuously. How much will the account be worth after 15 years?
Kala Reply
lim x to infinity e^1-e^-1/log(1+x)
given eccentricity and a point find the equiation
Moses Reply
12, 17, 22.... 25th term
Alexandra Reply
12, 17, 22.... 25th term
Akash
College algebra is really hard?
Shirleen Reply
Absolutely, for me. My problems with math started in First grade...involving a nun Sister Anastasia, bad vision, talking & getting expelled from Catholic school. When it comes to math I just can't focus and all I can hear is our family silverware banging and clanging on the pink Formica table.
Carole
I'm 13 and I understand it great
AJ
I am 1 year old but I can do it! 1+1=2 proof very hard for me though.
Atone
hi
Adu
Not really they are just easy concepts which can be understood if you have great basics. I am 14 I understood them easily.
Vedant
find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
I know this work
salma
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
Abhi
If f(x) = x-2 then, f(3) when 5f(x+1) 5((3-2)+1) 5(1+1) 5(2) 10
Augustine
how do they get the third part x = (32)5/4
kinnecy Reply
make 5/4 into a mixed number, make that a decimal, and then multiply 32 by the decimal 5/4 turns out to be
AJ
how
Sheref
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
hmm
Abhi
is it a question of log
Abhi
🤔.
Abhi
I rally confuse this number And equations too I need exactly help
salma
But this is not salma it's Faiza live in lousvile Ky I garbage this so I am going collage with JCTC that the of the collage thank you my friends
salma
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
hii
Uday
hi
salma
hi
Ayuba
Hello
opoku
hi
Ali
greetings from Iran
Ali
salut. from Algeria
Bach
hi
Nharnhar
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
A soccer field is a rectangle 130 meters wide and 110 meters long. The coach asks players to run from one corner to the other corner diagonally across. What is that distance, to the nearest tenths place.
Kimberly Reply
Jeannette has $5 and $10 bills in her wallet. The number of fives is three more than six times the number of tens. Let t represent the number of tens. Write an expression for the number of fives.
August Reply
What is the expressiin for seven less than four times the number of nickels
Leonardo Reply
How do i figure this problem out.
how do you translate this in Algebraic Expressions
linda Reply
why surface tension is zero at critical temperature
Shanjida
I think if critical temperature denote high temperature then a liquid stats boils that time the water stats to evaporate so some moles of h2o to up and due to high temp the bonding break they have low density so it can be a reason
s.
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris 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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