This paper presents a lecture video structuring and analysis scheme to provide students an efficient way to access the lecture content. Instead of using color-based or histogram-based methodologies, we propose a new edge-based shot boundary detection algorithm to accurately rebuild the slide structure. The proposed approach can successfully resist the unwanted influences induced from the variant illumination condition and occlusions. Besides, original slide content can be extracted excluding any obstruction by using human removing techniques. Furthermore, the teaching focus is analyzed so that this system becomes more useful for learning.

This paper proposes an indexing and teaching focus mining system for lecture videos recorded in an unconstraint environment. The slide structure can be reconstructed by an edge-based shot change detection algorithm. Besides, the teaching focus can be extracted according to instructor’s behavior, including the gesture, the lecture time for each slide, and the speech speed. Experiment results show the feasibility of the proposed method, that is, the slide shots can be correctly detected even if the illumination conditions is variant or the slides are obstructed by the instructor or students, and the teaching focus can be well extracted to provide learners an efficient way to study.

MOTIVATION: Homologous genomic sequences between species usually contain different rearrangement events. Whether some specific patterns existed in the breakpoint regions that caused such events to occur is still unclear. To resolve this question, it is necessary to determine the location of breakpoints at the nucleotide level. The availability of sequences near breakpoints would further facilitate the related studies. We thus need a tool that can identify breakpoints and align the neighboring sequences. Although local alignment tools can detect rearrangement events, they only report a set of discontinuous alignments, where the detailed alignments in the breakpoint regions are usually missing. Global alignment tools are even less appropriate for these tasks since most of them are designed to align the conserved regions between sequences in a consistent order, i.e. they do not consider rearrangement events. RESULTS: We propose an effective and efficient pairwise sequence alignment algorithm, called GR-Aligner (Genomic Rearrangement Aligner), which can find breakpoints of rearrangement events by integrating the forward and reverse alignments of the breakpoint regions flanked by homologously rearranged sequences. In addition, GR-Aligner also provides an option to view the alignments of sequences extended to the breakpoints. These outputs provide materials for studying possible evolutionary mechanisms and biological functionalities of the rearrangement.

The purpose of this research lies in the development of a user-key dependent removable visible watermarking scheme in JPEG compression domain. The protected images are embedded with the visible watermarks, and further compressed by JPEG compression. The visible watermarks only can be successfully removed by authorized user with the private key. Experimental results show the proposed scheme can recover images to the extent of JPEG-compression qualities.

This study reports the research findings on improving pronunciation learning by debugging practices. The mispronounced words usually uttered by learners are edited into conversations, and recorded on video. Students had to hear and comprehend the communication events to identify the mispronounced words. The debugging training has two purposes: (1) to identify and correct any mispronounced words, and (2) to enhance the pronunciation accuracy of the learners. To achieve these objectives, a video-enabled Web-based pronunciation debugging system is developed to facilitate this practice. Fourteen students utilized the system to assist pronunciation learning activities. The results of a paired-sample T test reveal that students did get improvement in pronunciation accuracy. Furthermore, students are found to have positive attitudes toward using the video-enabled Web-based pronunciation debugging system to facilitate pronunciation learning. Experimental results demonstrate that the debugging practices are effective in improving learners' pronunciation accuracy.

This paper presents a visualization tool, VisHD, that can visualize the spatial distribution of vector points in high dimensional feature space. It is important to handle high dimensional information in many areas of computer science. VisHD provides several methods for dimension reduction in order to map the data from high dimensional space to low dimensional one. Next, this system builds intuitive visualization for observing the characteristics of the data set, whether these data are pre-defined labels or not. In addition, some useful functions have been implemented to facilitate the information visualization. This paper, finally, gives some experiments and discussions for showing the abilities of VisHD for visualizing high-dimensional data.