9039594
TinyMotion: camera phone based interaction methods
This paper presents TinyMotion, a pure software approach that detects the movements of cell phones in real time by analyzing image sequences captured by the built-in camera. Typical movements that TinyMotion detects include - horizontal and vertical movements, rotational movements and tilt movements. In contrast to earlier work, TinyMotion does not require additional sensors, special scenes or backgrounds and can run on today's main-stream camera phones without hardware modification. We describe the design and implementation of TinyMotion and analyze the potential interactions that can leverage TinyMotion. Three applications and two games were created to test TinyMotion. Benchmarking results and usability study show that TinyMotion can detect camera movement reliably under most background and illumination conditions.
579393
Chinese input with keyboard and eye-tracking: an anatomical study
Chinese input presents unique challenges to the field of human computer interaction. This study provides an anatomical analysis of today's standard Chinese input process, which is based on pinyin, a phonetic spelling system in Roman characters. Through a combination of human performance modeling and experimentation, our study decomposed the Chinese input process into sub-tasks and found that choice reaction time and numeric keying, two component resulted from the large number of homophones in Chinese, were the major usability bottlenecks. Choice reaction alone took 36% of the total input time in our experiment. Numeric keying for multiple candidates selection tends to take the user's attention away from the computer visual screen. We designed and implemented the EASE (Eye Assisted Selection and Entry) system to help maintaining complete touch-typing experience without diverting visual (spacebar) and implicit eye-tracking to replace the numeric keystrokes. Our experiment showed that such a system could indeed work, even with today's imperfecteye-tracking technology.
17608350
End-user place annotation on mobile devices: a comparative study
Advances in Location-Based Services (LBS) are opening opportunities for using the location of people, places, and things to augment or streamline interaction. While computers work with physical locations like latitude and longitude directly, people usually think and speak in terms of places, which adds personal, environmental and social meaning to a location. To address this conceptual mismatch, location-aware applications must incorporate the notion of place to achieve their full potential. In this paper, we investigate four techniques for collecting end-user place annotations interactively using cell phones. The results from a usability study suggest that while all the four methods receive similar preference ratings in understandability, the "photo memo plus offline editing" method is the most favorite approach in ease of use. In addition, users indicated their desire to adopt more than one place annotation method in location-aware applications.
8517678
Camera phone based motion sensing: interaction techniques, applications and performance study
This paper presents TinyMotion, a pure software approach for detecting a mobile phone user's hand movement in real time by analyzing image sequences captured by the built-in camera. We present the design and implementation of TinyMotion and several interactive applications based on TinyMotion. Through both an informal evaluation and a formal 17-participant user study, we found that 1. TinyMotion can detect camera movement reliably under most background and illumination conditions. 2. Target acquisition tasks based on TinyMotion follow Fitts' law and Fitts law parameters can be used for TinyMotion based pointing performance measurement. 3. The users can use Vision TiltText, a TinyMotion enabled input method, to enter sentences faster than MultiTap with a few minutes of practicing. 4. Using camera phone as a handwriting capture device and performing large vocabulary, multilingual real time handwriting recognition on the cell phone are feasible. 5. TinyMotion based gaming is enjoyable and immediately available for the current generation camera phones. We also report user experiences and problems with TinyMotion based interaction as resources for future design and development of mobile interfaces.
207156320
Livenotes: a system for cooperative and augmented note-taking in lectures
We describe Livenotes, a shared whiteboard system and educational practice that uses wireless communication and tablet computing to support real-time conversations within small groups of students during lectures, independent of class size. We present an interface design that enables group members to interact with one another by taking lecture notes cooperatively, as well as to augment student note-taking by providing instructor slides in the background to annotate over. Livenotes was designed to facilitate more efficient, stimulating modes of learning that other collaborative approaches do not. We report how the system impacts cooperative learning in an undergraduate class and how students interacted with background slides in the workspace. We conclude with directions for improving the system and learning practice.
2749844
Image and Video Segmentation by Anisotropic Kernel Mean Shift
Mean shift is a nonparametric estimator of density which has been applied to image and video segmentation. Traditional mean shift based segmentation uses a radially symmetric kernel to estimate local density, which is not optimal in view of the often structured nature of image and more particularly video data. In this paper we present an anisotropic kernel mean shift in which the shape, scale, and orientation of the kernels adapt to the local structure of the image or video. We decompose the anisotropic kernel to provide handles for modifying the segmentation based on simple heuristics. Experimental results show that the anisotropic kernel mean shift outperforms the original mean shift on image and video segmentation in the following aspects: 1) it gets better results on general images and video in a smoothness sense; 2) the segmented results are more consistent with human visual saliency; 3) the algorithm is robust to initial parameters.
9854659
Query Processing for Distance Metrics
In applications such as vision and molecular biology, a common problem is to find the similar objects to a given target (according to some distance measure) in a large database. This paper presents a scheme for query processing in such situations. The basic strategy is to (partially) precompute inter-object distances, and by using the distance information and the triangle inequality, we eliminate the need to calculate certain object distances while evaluating queries. We propose several heuristics that may speed up query evaluation. A series of experiments are then performed to evaluate the effectiveness of our scheme and the relative performance of the heuristics for different queries. Finally we investigate the possibility of parallelizing our scheme through simulation. Our results show that parallelism is best applied in the later stages in evaluating a query.
8673951
An iterative optimization approach for unified image segmentation and matting
Separating a foreground object from the background in a static image involves determining both full and partial pixel coverages, also known as extracting a matte. Previous approaches require the input image to be presegmented into three regions: foreground, background and unknown, which are called a trimap. Partial opacity values are then computed only for pixels inside the unknown region. This presegmentation based approach fails for images with large portions of semitransparent foreground where the trimap is difficult to create even manually. In this paper, we combine the segmentation and matting problem together and propose a unified optimization approach based on belief propagation. We iteratively estimate the opacity value for every pixel in the image, based on a small sample of foreground and background pixels marked by the user. Experimental results show that compared with previous approaches, our method is more efficient to extract high quality mattes for foregrounds with significant semitransparent regions
17699044
Automated Discovery of Active Motifs in Multiple RNA Secondary Structures
In this paper we present a method for discovering approximately common motifs (also known as active motifs) in multiple RNA secondary structures. The secondary structures can be represented as ordered trees (i.e., the order among siblings matters). Motifs in these trees are connected subgraphs that can differ in both substitutions and deletions/insertions. The proposed method consists of two steps: (1) find candidate motifs in a small sample of the secondary structures; (2) search all of the secondary structures to determine how frequently these motifs occur (within the allowed approximation) in the secondary structures. To reduce the running time, we develop two optimization heuristics based on sampling and pattern matching techniques. Experimental results obtained by running these algorithms on both generated data and RNA secondary structures show the good performance of the algorithms. To demonstrate the utility of our algorithms, we discuss their applications to conducting the phylogenetic study of RNA sequences obtained from GenBank.
206339726
Soap-HT-BLAST: high throughput BLAST based on Web services
SUMMARY
A high throughput Basic Local Alignment Search Tool (BLAST) system based on Web services is implemented. It provides an alternative BLAST service and allows users to perform multiple BLAST queries at one run in a distributed, parallel environment through the Internet.


AVAILABILITY
It is available at http://mammoth.bii.a-star.edu.sg/webservices/htblast/index.html and at http://www.bii.a-star.edu.sg/jiren/download.html