42876940
An HMM-based speech recognition IC
This paper presents the design, simulation and measurement results of a Hidden Markov Model (HMM) based isolated word recognizer IC with double mixtures. Table look-up technique is employed in this design. The chip operates at 20 MHz at 3.3 V. The recognition time is 0.5 s for a 50-word speech library. The speech IC has been verified with 467 test speech data and the recognition accuracy is 93.8%. A reference software recognizer using the same algorithm and speech library has a recognition accuracy of 94.2%. The new speech IC that uses a table look up to reduce the complexity of the circuit has approximately the same recognition accuracy as an ideal software recognizer.
2587142
Using tone information in Cantonese continuous speech recognition
In Chinese languages, tones carry important information at various linguistic levels. This research is based on the belief that tone information, if acquired accurately and utilized effectively, contributes to the automatic speech recognition of Chinese. In particular, we focus on the Cantonese dialect, which is spoken by tens of millions of people in Southern China and Hong Kong. Cantonese is well known for its complicated tone system, which makes automatic tone recognition very difficult. This article describes an effective approach to explicit tone recognition of Cantonese in continuously spoken utterances. Tone feature vectors are derived, on a short-time basis, to characterize the syllable-wide patterns of F0 (fundamental frequency) and energy movements. A moving-window normalization technique is proposed to reduce the tone-irrelevant fluctuation of F0 and energy features. Hidden Markov models are employed for context-dependent acoustic modeling of different tones. A tone recognition accuracy of 66.4% has been achieved in the speaker-independent case. The recognized tone patterns are then utilized to assist Cantonese large-vocabulary continuous speech recognition (LVCSR) via a lattice expansion approach. Experimental results show that reliable tone information helps to improve the overall performance of LVCSR.
21281832
Progressive mesh metamorphosis
This paper describes a new integrated scheme for metamorphosis between two closed manifold genus-0 polyhedral models. Spherical parameterizations of the source and target models are created first. To control the morphing, any number of feature vertex pairs is specified and a fold-over free warping method is used to align two spherical embeddings. Our method does not create a merged meta-mesh or execute re-meshing to construct a common connectivity for morphs. Alternatively, a scheme for the progressive connectivity transformation of two spherical parameterizations is employed to generate the intermediate meshes. A novel semi-overlay with a geomorph scheme is proposed to reduce the popping effects caused by the connectivity transformation. We demonstrate several examples of aesthetically pleasing morphing sequences using the proposed scheme. Copyright © 2005 John Wiley & Sons, Ltd.
8163714
Scaling Laws in Natural Scenes and the Inference of 3D Shape
This paper explores the statistical relationship between natural images and their underlying range (depth) images. We look at how this relationship changes over scale, and how this information can be used to enhance low resolution range data using a full resolution intensity image. Based on our findings, we propose an extension to an existing technique known as shape recipes [3], and the success of the two methods are compared using images and laser scans of real scenes. Our extension is shown to provide a two-fold improvement over the current method. Furthermore, we demonstrate that ideal linear shape-from-shading filters, when learned from natural scenes, may derive even more strength from shadow cues than from the traditional linear-Lambertian shading cues.
7135959
On original generation of structure in legal documents
This position paper advocates a vision in the development of automated legal reasoning and presents evidence supporting the plausibility of that vision. The paper observes that original creation of documents of legal import in either fully formal or semistructured form offers the prospect of greatly reducing the cost and expanding the scope of knowledge engineering for legal reasoning. This, it is claimed, is most likely to be achieved via formalization of various sublanguages of legal discourse. SeaSpeak is an example of such a sublanguage and it appears to be amenable to full formalization. Short of that, much can be done with partial formalization and semistructured documents. The paper presents a tabular format for message expression, motivated by a formal agent communication language.
207739442
Independent Component Analysis Using an Extended Infomax Algorithm for Mixed Subgaussian and Supergaussian Sources
An extension of the infomax algorithm of Bell and Sejnowski (1995) is presented that is able blindly to separate mixed signals with sub- and supergaussian source distributions. This was achieved by using a simple type of learning rule first derived by Girolami (1997) by choosing negentropy as a projection pursuit index. Parameterized probability distributions that have sub- and supergaussian regimes were used to derive a general learning rule that preserves the simple architecture proposed by Bell and Sejnowski (1995), is optimized using the natural gradient by Amari (1998), and uses the stability analysis of Cardoso and Laheld (1996) to switch between sub- and supergaussian regimes. We demonstrate that the extended infomax algorithm is able to separate 20 sources with a variety of source distributions easily. Applied to high-dimensional data from electroencephalographic recordings, it is effective at separating artifacts such as eye blinks and line noise from weaker electrical signals that arise from sources in the brain.
10997807
Resource bounded symmetry of information revisited
The information contained in a string x about a string y is the difference between the Kolmogorov complexity of y and the conditional Kolmogorov complexity of y given x, i.e., I(x : y)=C(y)-C(y|x). The Kolmogorov-Levin Theorem says that I(x : y) is symmetric up to a small additive term. We investigate if this property also holds for several versions of polynomial time-bounded Kolmogorov complexity.We study symmetry of information for some variants of distinguishing complexity CD where CD(x) is the length of a shortest program which accepts x and only x. We show relativized worlds where symmetry of information does not hold in a strong way for deterministic and nondeterministic polynomial time distinguishing complexities CDpoly and CNDpoly. On the other hand, for nondeterministic polynomial time distinguishing complexity with randomness, CAMDpoly, we show that symmetry of information holds for most pairs of strings in any set in NP. Our techniques extend work of Buhrman et al. (Language compression and pseudorandom generators, in: Proc. 19th IEEE Conf. on Computational Complexity, IEEE, New York, 2004, pp. 15-28) on language compression by AM algorithms, and have the following application to the compression of samplable sources, introduced in Trevisan et al. (Compression of sample sources, in: Proc. 19th IEEE Conf. on Computational Complexity, IEEE, New York, 2004, pp. 1-15): any element x in the support of a polynomial time samplable source X can be given a description of size - log Pr[X = x] + O(log3 n), from which x can be recovered by an AM algorithm.