We study the redundancy of Huffman code (which, incidentally, is as old as the author of this paper). It has been known from the inception of this code that in the worst case Huffman code redundancy defined as the excess of the code length over the optimal (ideal) code length is not more than onc. Over more than forty years, insightful, elegant and useful constructions have been set up to deter...

We examine the problem of deciphering a file that has been Huffman coded, but not otherwise encrypted. We find that a Huffman code can be surprisingly difficult to cryptanalyze. We present a detailed analysis of the situation for a three-symbol source alphabet and present some results for general finite alphabets.

Abstruct-In honor of the twenty-fifth amdversary of Huffman coding, four new results about Huffman codes are presented. 'Ibe ffrst result shows that a binary prefix condition code is a Huffmau code iff the intermediate and terminal nodes id the code tree can be listed by nonin-creasing probabiuty so that each node in the fist is adjacent to its sibling. The second result upper bounds the redund...

Iterative decoding of JPEG images does not perform well due to the poor distance property of the original JPEG Huffman codes. We propose a symmetric RVLC with large free distance which can dramatically improve the system performance when iterative decoding is performed. Simulation results indicate up to 4 dB coding gain is achievable. There is a significant body of literature (see references in...

There has been much interest in recent years in bounds on the redundancy of Huffman codes, given only partial information about the source word distribution, such as the probability of the most likely source. This work determines upper and lower bounds for the redundancy of Huffman codes of source words which are binomially distributed. Since the complete distribution is known, it is possible t...

Novel maximal coding compression techniques for the most important file-the text file of any full-text retrieval system are discussed in this paper. As a continuation of our previous work, we show that the optimal maximal coding schemes coincide with the optimal uniquely decodable coding schemes. An efficient algorithm generating an optimal maximal code (or an optimal uniquely decodable code) i...

Runtime code generation is not a new concept [1] and has been widely used for improving the performance of programs at runtime. Typical examples include Just-In-Time (JIT) compilation [2], [3] and dynamic optimization systems [4], [5]. A class of programs that can benefit from runtime code generation are programs with an execution path that is determined by runtime data, which remain unchanged ...

We show that the space of all binary Huffman codes for a finite alphabet defines a lattice, ordered by the imbalance of the code trees. Representing code trees as path-length sequences, we show that the imbalance ordering is closely related to a majorization ordering on real-valued sequences that correspond to discrete probability density functions. Furthermore, this tree imbalance is a partial...

It is well known that the efficiency of noiseless coding may be improved by coding extensions of the source; for large extensions the efficiency is arbitrarily close to unity. This paper shows that the efficiency is not always improved just by coding the next extension. In some cases the code of a larger extension is markedly less efficient than its predecessor, although always within the theor...