Based on the breadth-first search manner and the level-compression technique, this letter first presents a new array data structure to represent the classical Huffman tree. Then, the decoding algorithm is given. Both the memory and the decoding time required in the proposed method are less than those of previous methods. Some experimentations are carried out to demonstrate the advantages of the...

In this paper we present an analysis of the storage complexity of Huffman codes, Tunstall codes and arithmetic codes in various implementations and relate this to the achieved redundancies. It turns out that there exist efficient implementations of both Huffman and Tunstall codes and that their approximations result in arithmetic codes. Although not optimal, the arithmetic codes still have a be...

The Adaptive Wavelet Image Compression (AWIC) algorithm is a fast, simple waveletbased image compression technique that follows the classical paradigm of image transformation, quantization, and entropy encoding. A key component of AWIC is a technique of channel symbol definition that provides greatly reduced Huffman table encoding costs, allowing optimal Huffman codewords to be generated and us...

We study the new problem of Huffman-like codes subject to individual restrictions on the code-word lengths of a subset of the source words. These are prefix codes with minimal expected code-word length for a random source where additionally the code-word lengths of a subset of the source words is prescribed, possibly differently for every such source word. Based on a structural analysis of prop...

Shannon’s noiseless coding theorem tells us how compactly we can compress messages in which all letters are drawn independently from an alphabet A and we are given the probability pa of each letter a ∈ A appearing in the message. Shannon’s theorem says that, for random messages with n letters, the expected number of bits we need to transmit is at least nH(p) = −n ∑ a∈A pa log2 pa bits, and ther...

It is proven that for every random variable with a countably infinite set of outcomes and finite entropy there exists an optimal prefix code which can be constructed from Huffman codes for truncated versions of the random variable, and that the average lengths of any sequence of Huffman codes for the truncated versions converge to that of the optimal code. Also, it is shown that every optimal i...

It is proven that for every random variable with a countably infinite set of outcomes and finite entropy there exists an optimal prefix code which can be constructed from Huffman codes for truncated versions of the random variable, and that the average lengths of any sequence of Huffman codes for the truncated versions converge to that of the optimal code. Also, it is shown that every optimal i...

Faults due to the incorrect functioning of the computation system, or the transmission errors of the internal data, could corrupt the output code stream of the Huffman encoder. In this paper, a fault detection method is proposed for the Huffman encoding system, which is implemented in the JPEG image compression standard [1]. The detection method based on the information input and the code strea...

-It is demonstrated that for finite-alphabet, Kth order ergodic Markov Sources (i.e., memory of K letters), a variable-to-fixed code is better than the best fixed-to-variable code (Huffman code). It is shown how to construct a variable-to-fixed length code for a Kth order ergodic Markov source, which compresses more effectively than the best fixed-to-variable code (Huffman code).

Steganography is data hiding technique that is mostly used. It uses cover object of type text, images, and videos. The paper presents a new devised algorithm to hide text in any colored image of any size using Huffman encryption and 2D Wavelet Transform. We presented simulated results which prove that there is very negligible image quality degradation. We used PSNR metric for this purpose. The ...