HW9_JPEG - 0.0085 0.0044 0.0086 0.0046-0.0019 0.0036...

Info icon This preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Polytechnic University, Dept. Electrical and Computer Engineering EE3414 Multimedia Communication System I Spring 2006, Yao Wang __________________________________________________________________________________________________ Homework 9 (JPEG Image Coding) Written Assignment : 1. Describe briefly how JPEG compresses an image. You may want to break down your discussion into three parts: a. How does JPEG compress a 8x8 image block (three steps are involved) b. How does JPEG compress a gray-scale image c. How does JPEG compress a RGB color image 2. Describe what does a scalable bit stream mean and why is scalability a desired feature for image coding and transmission. What is the difference between quality scalability and spatial scalability? 3. Suppose the DCT coefficient matrix for an 4x4 image block is as shown below ( dctblock ). a. Quantize its DCT coefficients using the quantization matrix Q given below, assuming QP=1. Determine the quantized coefficient indices and quantized values.
Image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: , 0.0085 0.0044 0.0086 0.0046-0.0019 0.0036 0.0207-0.0086-0.0071 0.0877 0.0033-0.0134 0.0912 0.0466-0.0500-1.3676 * 003 . 1 + = e dctblock , 120 103 78 49 103 68 37 18 69 40 16 14 51 24 10 16 = Q b. Represent the quantized indices using the run-length representation. That is, generate a series of symbols, the first being the quantized DC index, the following symbols each consisting of a length of zeros and the following non-zero index, the last symbol is EOB (end of block). c. Encode the DC index and the runlength symbols from (b) using the JPEG coding method, with the coding tables given in the lecture note. For this problem, assuming the quantized index for the DC coefficient of the previous block is 60. 4. Determine the Y,Cr,Cb values for a pixel with (R,G,B) value of R=200,G=150, B=50....
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern