Article history: Received 9 January 2016 Received in revised form 15 June 2016 Accepted 25 August 2016 Available online xxxx Communicated by W. Cary Huffman

In this paper we present some new results on the approximate parallel construction of Huuman codes. Our algorithm achieves linear work and logarithmic time, provided that the initial set of elements is sorted. This is the rst parallel algorithm for that problem with the optimal time and work. Combining our approach with the best known parallel sorting algorithms we can construct an almost optim...

In this paper, we revisit the classical data compression problem for domain specific texts. It is well-known that classical Huffman algorithm is optimal with respect to prefix encoding and the compression is done at character level. Since many data transfer are domain specific, for example, downloading of lecture notes, web-blogs, etc., it is natural to think of data compression in larger dimen...

It has been recently proved that the redundancy r of any discrete memoryless source satisses r 1?H(p N), where p N is the least likely source letter probability. We prove that this bound is achieved only by sources consisting of two letters and that a sharper bound holds if the number of source letters is greater than two. Also provided is a new upper bound on r, as function of the two least li...

An n symbol source which has a Huffman code with codelength vector Ln = (1, 2, 3, · · · , n − 2, n − 1, n − 1) is called an anti-uniform source. In this paper, it is shown that for this class of sources, the optimal fix-free code and symmetric fix-free code is C∗ n = (0, 11, 101, 1001, · · · , 1 n−2 { }} { 0 · · · 0 1).