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[[Category:2010 Fall ECE 438 Boutin]]
 
[[Category:2010 Fall ECE 438 Boutin]]
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[[Category:Problem_solving]]
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[[Category:ECE438]]
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[[Category:digital signal processing]]
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== Quiz Questions Pool for Week 14 ==
 
== Quiz Questions Pool for Week 14 ==
 
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c. Find a simple expression for the frequency response (DSFT) H(u,v) of this filter.
 
c. Find a simple expression for the frequency response (DSFT) H(u,v) of this filter.
 
d. Plot H(u,v) along the u axis (v = 0) , along the v axis (u = 0) , along the line u = v , and along the line u = -v.
 
  
 
* [[ECE438_Week14_Quiz_Q3sol|Solution]].
 
* [[ECE438_Week14_Quiz_Q3sol|Solution]].
 
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Q4. Consider the following discrete space system with input x[m,n] and output y[m,n]given by
  
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<math>y[m,n]=x[m,n]+\frac{1}{2}y[m+1,n-1]</math>
  
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Compute the transfer function
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<math>H(z_1 ,z_2)=\frac{Y(z_1 ,z_2)}{X(z_1 ,z_2)}</math>
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* [[ECE438_Week14_Quiz_Q4sol|Solution]].
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Q5. Consider the following discrete space system
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[[Image:Quiz14Q5.jpg]]
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where <math>b(i,j)</math> is the quantized binary image, <math>f(i,j)</math> is the input and <math>\tilde{f}(i,j)</math> is the modified image by means of the past quantization errors.
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Furthermore we have that
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:<math>\begin{align}e(i,j)&=\tilde{f}(i,j)-b(i,j) \\ \tilde{f}(i,j)&=f(i,j)+H(i,j)\ast e(i,j) \\ \end{align}</math>
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Now, we have <math>H(i,j)=\delta(i-1,j)\,\!</math> is a strictly causal filter and the quantizer <math>Q(\tilde{f})</math> given as
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:<math>Q(\tilde{f})=\left\{ \begin{array}{ll}1,& \tilde{f}(i,j)>0.5 \\ 0, & \tilde{f}(i,j)\leq 0.5 \end{array} \right. </math>
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Assuming that <math>e(i,j)=0</math> for <math>i<0</math> and <math>j<0</math> and the input <math>f(i,j)</math> to be defined as
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[[Image:Quiz14Q5_1.jpg]]
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a. compute the modified input <math>\tilde{f}(i,j)</math>.
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[[Image:Quiz14Q5_2.jpg]]
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b. compute the output <math>b(i,j)</math>.
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[[Image:Quiz14Q5_3.jpg]]
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* [[ECE438_Week14_Quiz_Q5sol|Solution]].
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----
 
Back to [[ECE438_Lab_Fall_2010|ECE 438 Fall 2010 Lab Wiki Page]]
 
Back to [[ECE438_Lab_Fall_2010|ECE 438 Fall 2010 Lab Wiki Page]]
  
 
Back to [[2010_Fall_ECE_438_Boutin|ECE 438 Fall 2010]]
 
Back to [[2010_Fall_ECE_438_Boutin|ECE 438 Fall 2010]]

Latest revision as of 09:43, 11 November 2011


Quiz Questions Pool for Week 14


Q1. Assume we know (or can measure) a function

$ \begin{align} p(x) &= \int_{-\infty}^{\infty}f(x,y)dy \end{align} $

Using the definition of the CSFT, derive an expression for F(u,0) in terms of the function p(x).


Q2. Consider the following 2D system with input x(m,n) and output y(m,n)

$ y(m,n) = x(m,n) + \lambda \left( x(m,n) - \frac{1}{9} \sum_{k=-1}^{1}\sum_{l=-1}^{1}x(m-k,n-l) \right) $

a. Is this a linear system? Is it space invariant?
b. What is the 2D impulse response of this system?
c. Calculate its frequency response H(u,v).
d. Describe how the filter behaves when $ \lambda $ is positive and large.
e. Describe how the filter behaves when $ \lambda $ is negative and bigger than -1.


Q3. Consider a 3 * 3 FIR filter with coefficients h[m, n]

Q3 table.jpg

a. Find a difference equation that can be used to implement this filter.

b. Given an input image, find the center pixel value of output image.

Q3 inputimg.jpg

c. Find a simple expression for the frequency response (DSFT) H(u,v) of this filter.


Q4. Consider the following discrete space system with input x[m,n] and output y[m,n]given by

$ y[m,n]=x[m,n]+\frac{1}{2}y[m+1,n-1] $

Compute the transfer function

$ H(z_1 ,z_2)=\frac{Y(z_1 ,z_2)}{X(z_1 ,z_2)} $


Q5. Consider the following discrete space system

Quiz14Q5.jpg

where $ b(i,j) $ is the quantized binary image, $ f(i,j) $ is the input and $ \tilde{f}(i,j) $ is the modified image by means of the past quantization errors.

Furthermore we have that

$ \begin{align}e(i,j)&=\tilde{f}(i,j)-b(i,j) \\ \tilde{f}(i,j)&=f(i,j)+H(i,j)\ast e(i,j) \\ \end{align} $

Now, we have $ H(i,j)=\delta(i-1,j)\,\! $ is a strictly causal filter and the quantizer $ Q(\tilde{f}) $ given as

$ Q(\tilde{f})=\left\{ \begin{array}{ll}1,& \tilde{f}(i,j)>0.5 \\ 0, & \tilde{f}(i,j)\leq 0.5 \end{array} \right. $

Assuming that $ e(i,j)=0 $ for $ i<0 $ and $ j<0 $ and the input $ f(i,j) $ to be defined as

Quiz14Q5 1.jpg

a. compute the modified input $ \tilde{f}(i,j) $.

Quiz14Q5 2.jpg

b. compute the output $ b(i,j) $.

Quiz14Q5 3.jpg


Back to ECE 438 Fall 2010 Lab Wiki Page

Back to ECE 438 Fall 2010

Alumni Liaison

Basic linear algebra uncovers and clarifies very important geometry and algebra.

Dr. Paul Garrett