Update rules for learning in dynamic time warping spaces are based on optimal warping paths between parameter and input time series. In general, optimal warping paths are not unique resulting in adverse effects in theory and practice. Under the assumption of squared error local costs, we show that no two warping paths have identical costs almost everywhere in a measure-theoretic sense. Two dire...

In this paper we study the eeect of vocal tract normalization (VTN) on the word error rate (WER) in speaker independent large vocabulary speech recognition. Evaluation test results are reported for the German VerbMobil II (VM II) and the English Wall Street Journal (WSJ) corpus. In particular, we analyse: the eeect of the type of warping function (linear vs. non-linear) on the WER; diierent met...

In this work we extend the test utterance adaptation technique used in vocal tract length normalization to a larger number of speaker characteristic features. We perform partially joint estimation of four features: the VTLN warping factor, the corner position of the piece-wise linear warping function, spectral tilt in voiced segments, and model variance scaling. In experiments on the Swedish PF...

In this paper, a new warping technique called contour-based warping is presented. Feature contours of objects are de ned and mapped to their target shapes. This allows the user greater exibility in de ning the warping with minimal e ort. Two image warping methods are introduced in this paper and both are based on the concept of mapping contours. The peel-and-resample method can warp simple imag...

A warping operator consists of an invertible axisdeformation applied either in the signal domain or in thecorresponding Fourier domain. Additionally, a warping trans-formation is usually required to preserve the signal energy, thuspreserving orthogonality and being invertible by its adjoint.Initially, the design of such operators has been motivated bythe idea of suitably...

A new efficient two-dimensional warping algorithm is presented, in which sub-optimal warping is attained by iterating DP-based local optimization of warp on partially overlapping subplane sequence. From an experimental comparison with a conventional approximation algorithm based on beam search DP, relative superiority of the proposed algorithm is established. key words: two-dimensional warping,...

Deliberate nonuniform sampling promises increased equivalent sampling rates with reduced overall hardware costs of the DSP system. The equivalent sampling rate is the sampling rate that a uniform sampling device would require in order to achieve the same processing bandwidth. Equivalent bandwidths of realizable systems may well extend into the GHz range while the mean sampling rate stays in the...

An accurate comparison of multimodal and/or interindividual 3D image datasets of brains requires geometric transformation techniques (warping) to reduce geometric variations. Here, a subset of warping techniques, namely point-based warping, is investigated. For this kind of warping landmarks between datasets have to be defined. In large 3D datasets manually setting of landmarks is timeconsuming...