In this paper we present the generalization of the test sequencing problem, originally defined for symmetrical tests, that also covers asymmetrical tests. We prove that the same heuristics that has been employed in the traditional solution of the problem (e.g., the AO∗ algorithm with heuristics based on Huffman’s coding) can be employed also for the generalized case. Examples are given to illus...

We present a novel 3D object retrieval method that relies upon a hybrid descriptor which is composed of 2D features based on depth buffers and 3D features based on spherical harmonics. To compensate for rotation, two alignment methods, namely CPCA and NPCA, are used while compactness is supported via scalar feature quantization to a set of values that is further compressed using Huffman coding....

We consider the problem of constructing and transmitting the prelude for Huffman coding. With careful organization of the required operations and an appropriate representation for the prelude, it is possible to make semistatic coding efficient even when , the size of the source alphabet, is of the same magnitude as , the length of the message being coded. The proposed structures are of direct r...

Efficient bit-representation or compression of documents is an important issue in many applications. The amount of compression depends on the document contents such as written scripts, diagrams, tables, etc. The contents of the document determine the limit of this compression. In the CCITI" Recommendation T.4, 'Standardization of group 3 apparatus for document transmission', a modified Huffman ...

We describe the implementation of a data compression scheme as an integral and transparent layer within a full-text retrieval system. Using a semi-static word-based compression model, the space needed to store the text is under 30% of the original requirement. The model is used in conjunction with canonical Huffman coding, and together these two paradigms provide fast decompression. Experiments...

Here is proposed a review of the different choices to structure spike trains, using deterministic metrics. Temporal constraints observed in biological or computational spike trains are first taken into account The relation with existing neural codes (rate coding, rank coding, phase coding, ..) is then discussed. To which extend the “neural code” contained in spike trains is related to a metric ...

Although a distributed index on a distributed hash table (DHT) enables efficient document query processing in Peer-to-Peer information retrieval (P2P IR), the index costs a lot to construct and it tends to be an unfair management because of the unbalanced term frequency distribution. We devised a new distributed index, named Huffman-DHT, for P2P IR. The new index uses an algorithm similar to Hu...

A speech/audio codec based on Frequency Domain Linear Prediction (FDLP) exploits auto-regressive modeling to approximate instantaneous energy in critical frequency sub-bands of relatively long input segments. The current version of the FDLP codec operating at 66 kbps has been shown to provide comparable subjective listening quality results to state-of-theart codecs on similar bit-rates even wit...

Huffman coding is often presented as the optimal solution to Twenty Questions. However, a caveat is that Twenty Questions games always end with a reply of “Yes,” whereas Huffman codewords need not obey this constraint. We bring resolution to this issue, and prove that the average number of questions still lies between H(X) and H(X) + 1.

We introduce a novel method for representing and coding wideband signals using permutations. The signal samples are first sorted, and then encoded using Differential Pulse Coding Modulation. We show that our method is optimal for DPCM coding and develop a novel algorithm for encoding the permutation information efficiently. We show that the new algorithm achieves coding gains over Huffman coding.