Homework 2

Due Jan 30


1. From the alphabet {a,b,c,d,e}, find upper and lower limits for the string dab using all 3 versions of arithmetic coding:
  1. with uniform probabilities (p=0.2)
  2. with probabilities p(a)=0.6, p(b)=0.1, p(c)=0.1, p(d)=0.1, p(e)=0.1.
  3. with dynamic probabilities that change with each new character.

2. Find the 3 character string corresponding to the number 0.123 using the 5 character alphabet from problem 1.

3. Use 4 bit delta coding to encode the sequence (12, 17, 21, 10, 0, 5, 15, 14). Show the reconstruction that would result.