This paper establishes a new coherent framework to extend the class of unitary warping operators to the case of discrete–time sequences. Providing some a priori considerations on signals, we show that the class of discrete–time warping operators finds a natural description in linear shift– invariant spaces. On such spaces, any discrete–time warping operator can be seen as a non–uniform weighted...

This thesis explores performance criteria adequate to validate simulation models. An overview on the most widely performance criteria used in literature is firstly provided. The thesis proceeds with the proposal of two new criteria that assess the distortion of the warping path obtained after applying the Dynamic Time Warping algorithm: the Warping Path Distortion (WPD) and the Percentage Warpi...

A method is proposed to improve any temporal pattern recognition system by time warping each pattern before presentation to the recognition system. The time warping function for a pattern is generated by repeated local application of a neural network to sections of the pattern. The output of this neural network is the slope of the warping function, and the internal weight parameters are trained...

Warping can be used to reduce interindividual structural variations of 3D image datasets of brains by generating a standard brain and subsequent matching of individual datasets to this reference system. Point-based warping uses structural information (landmarks) to construct the spatial correspondence between the datasets. For this we compare the performance of three landmark detection algorith...

Vocal tract length normalization is an important feature normalization technique that can be used to perform speaker adaptation when very little adaptation data is available. It was shown earlier that VTLN can be applied to statistical speech synthesis and was shown to give additive improvements to CMLLR. This paper presents an EM optimization for estimating more accurate warping factors. The E...

Vocal tract length normalization is an important feature normalization technique that can be used to perform speaker adaptation when very little adaptation data is available. It was shown earlier that VTLN can be applied to statistical speech synthesis and was shown to give additive improvements to CMLLR. This paper presents an EM optimization for estimating more accurate warping factors. The E...

In this paper! we present improvements over the original scalecepstrum proposed in [ 11. The scalecepstrum was motivated by a desire to normalize the first-order effects of differences in vocal-tract lengths for a given vowel. Our subsequent work [2] has shown that a more appropriate frequency-warping than the log-warping used in [l] is necessary to account for the frequency dependency of the s...

We present a technique for efficiently generating photo-realistic pictures of halos and inserting them into existing photographs. First, we describe an algorithm for producing images of halos from physical parameters either coming from existing photographs or supplied by the user. The problem with the resulting images is that they are sampled in a non-uniform way. Then, we propose a specific al...

Retrieval of similar heart sounds from a sound database has applications in physician training, diagnostic screening, and decision support. In this paper, we exploit a visual rendering of heart sounds and model the morphological variations of audio envelopes through a constrained non-rigid translation transform. Similar heart sounds are then retrieved by recovering the corresponding alignment t...

We outline our seamless tiled display system for interactive 3D graphics applications that is low-cost, easy to calibrate, scalable, and portable. Our system achieves geometric alignment in software by pre-warping the 3D space in contrast with the current systems that usually achieve this by 2D image pre-warping. Our system accomplishes this through real-time image capture from a digital camcor...