ECE178 HW #4DUE: Friday, October 23, 2009 (by 5PM in the HW box)Questions 0 to 4 are from the 3rdchapter of Digital Image Processing book by Gonzalezand Woods (3rdEdition).Q0. Review textbook problems 3.16, 3.19, 3.24, 3.25, 3.28. No need to turn in solutions to theseproblems.Q1. problem 3.13Q2. problem 3.14Q3. problem 3.17Q4. problem 3.23Q4. Write a MATLAB program to reduce the effect of 1-bit quantization using “Floyd-SteinbergDithering Algorithm”. Compare your results with uniform quantization without dithering.Comment on the differences. Use the “lena.gif” (See class website www.ece.ucsb.edu/~manj/ece178) to test your program.In the “Floyd-Steinberg Dithering Algorithm” quantization error introduced at each pixel isspread over the neighboring pixels as follows:Quantization error observed at pixel (i, j) is diffused to the right, lower left, below and lowerright pixels with the following weights (7/16, 3/16, 5/16, 1/16). Here, note that the weightssum up to 1.Pseudo-code for the algorithm:1for i = 1 to heightfor j = 1 to widthI2(i,j) = Q(I(i,j));error = I(x,y) − I2(x,y);I(i,j+1) += 7 ∗ error/16;I(i+1,j−1) += 3∗error/16;I(i+1,j) += 5 ∗ error/16;I(i+1,j+1) += error/16;end forend forHere Q(.) represents inform quantization operator. In this homework, assuming that I(i, j)is uniformly distributed over [0, 1], Q(I(i, j)) can be defined as follows:Q(I(i, j)) =1 I(i, j) ≥ 0.50 elseThings to turn in:(a) M-file(b) Output of uniform quantization(c) Output of “Floyd-Steinberg Dithering Algorithm”(d) Comments on the differences between
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