35666520
Automatic Lyrics Alignment on Popular Music
53788593
A fast recursive 3D model reconstruction algorithm for multimedia applications
A recursive two-step method to recover structure and motion from image sequences based on Kalman filtering is described in this paper. The algorithm consists of two major steps. The first step is an extended Kalman filter for the estimation of the object's pose. The second step is a set of extended Kalman filters, one for each model point, for refining the positions of the model features in the 3D space. The initial guess is a planar model formed under the assumption of orthographic projection on the first image. These two steps alternate from frames to frames. The planar model converges to the final structure as the image sequence is scanned sequentially. The performance of the algorithm is demonstrated with both synthetic data and real world objects. Comparisons with different approaches have been performed and show that our method is more efficient.
2219807
Computing Pose Sequences Directly from Videos
An innovative extended Kalman filter (EKF) algorithm for pose tracking has been proposed in this paper. It has the advantages of both structure and motion-based (SAM-based) and traditional model-based pose estimation algorithms. With no prior information about the scene, the pose sequence can be computed directly from images while the updating of the 3-D structure is not necessary. To achieve the goal, a constant velocity motion model is used as the dynamic system and the trifocal tensor point transfer function is applied to the measurement model of the filter. The resulting algorithm is stable, accurate and efficient. An empirical comparison with existing EKFs which deal with the same problem has been made and shows that our approach outperformed the others. The proposed method has been tested with various video sequences to demonstrate its performance in real situations.
28364216
Dynamic Programming in the Recognition of Connected Handwritten Script
3120289
Recursive Recovery of Position and Orientation from Stereo Image Sequences without Three-Dimensional Structures
Traditional vision-based 3-D motion estimation algorithms for robots require given or calculated 3-D models while the motion is being tracked. We propose a high-speed extended-Kalman-filter-based approach that recovers position and orientation from stereo image sequences without prior knowledge as well as the procedure for the reconstruction of 3-D structures. Empowered by the use of the trifocal tensor, the computation step of 3-D models can be eliminated. The algorithm is thus more flexible and can be applied to a wide range of domains. The twist motion model is also adopted to parameterize the 3-D motion such that the motion representation in the proposed algorithm is robust and minimal. As the number of parameters to be estimated is reduced, our algorithm is more efficient, stable and accurate compared to traditional approaches. The proposed method has been verified using a real image sequence with ground truth.
13225873
Model reconstruction and pose acquisition using extended Lowe's method
Finding the pose and structure of an unknown object from an image sequence has many applications in graphics, virtual reality, and multimedia processing. In this paper, we address this problem by using a two-stage iterative method. Starting from an initial guess of the structure, the first stage estimates the pose of the object. The second stage uses the estimated pose information to refine the structure. This process is repeated until the difference between the observed data and data re-projected from the estimated model is minimized. This method is a variation of the classical bundle adjustment method, but is faster in execution and is simpler to implement. We used the Kanade-Lucas-Tomasi feature tracker for obtaining the image features. Synthetic and real data have been tested with good results.
33806006
On migrating a legacy application to the palm platform
Handheld computing devices such as personal digital assistants (PDAs) and the latest mobile phones are becoming widespread, so migrating desktop applications to these platforms is of great interest to developers. However, little information is available to guide the novice especially for the palm OS, the,most popular platform in the PDA and smartphone arena. This paper highlights the migration challenges involved and potential directions in easing this reengineering process. To explore the practical understanding and reengineering issues, a large legacy application was partially migrated to palm OS.
10398473
Structural Redocumentation: A Case Study
Most software documentation typically describes the program at the algorithm and data-structure level. For large legacy systems, understanding the system's architecture is more important. The authors propose a method of reverse engineering through redocumentation that promises to extend the useful life of large systems. >
16840924
Improving Transliteration with Precise Alignment of Phoneme Chunks and Using Contextual Features
Automatic transliteration of foreign names is basically regarded as a diminutive clone of the machine translation (MT) problem. It thus follows IBM's conventional MT models under the source-channel framework. Nonetheless, some parameters of this model dealing with zero-fertility words in the target sequences, can negatively impact transliteration effectiveness because of the inevitable inverted conditional probability estimation. Instead of source-channel, this paper presents a direct probabilistic transliteration model using contextual features of phonemes with a tailored alignment scheme for phoneme chunks. Experiments demonstrate superior performance over the source-channel for the task of English-Chinese transliteration.
26459571
Geolocation for partially polarized electromagnetic sources using multiple sparsely and uniformly spaced "spatially stretched vector sensors"
A new angle-of-arrival estimation technique is developed using an array of "spatially stretched electromagnetic vector sensors" (each of which comprises a dipole triad plus a spatially displaced loop triad) for completely polarized, partially polarized and/or unpolarized incident signals. A dipole (loop) triad is composed of three identical, spatially co-located but orthogonally oriented electrically short dipoles (magnetically small loops) distinctly measuring all three electric-field (magnetic-field) components of the (possibly) partially polarized incident wave-field. The vector cross-product direction finding approach is herein generalized to allow: (1) any arbitrary displacement between the dipole triad and the loop triad comprising the six-component electromagnetic vector sensor, thereby reducing the adverse effects of inter-antenna mutual coupling, (2) any unknown temporal phase delay between the dipole triad and the loop triad (a common situation in electromagnetics), (3) the incident electromagnetic signals to be arbitrarily partially polarized or unpolarized. Simulations demonstrate the efficacy of this new technique.
750461
A Phonetic-Based Approach to Chinese Chat Text Normalization
Chatting is a popular communication media on the Internet via ICQ, chat rooms, etc. Chat language is different from natural language due to its anomalous and dynamic natures, which renders conventional NLP tools inapplicable. The dynamic problem is enormously troublesome because it makes static chat language corpus outdated quickly in representing contemporary chat language. To address the dynamic problem, we propose the phonetic mapping models to present mappings between chat terms and standard words via phonetic transcription, i.e. Chinese Pinyin in our case. Different from character mappings, the phonetic mappings can be constructed from available standard Chinese corpus. To perform the task of dynamic chat language term normalization, we extend the source channel model by incorporating the phonetic mapping models. Experimental results show that this method is effective and stable in normalizing dynamic chat language terms.