In CG animation, the method for modeling of CG characters such as humans or animals is important. If these shapes are represented by parametric surfaces, such as Bezier, B-spline, or NURBS surfaces, complex procedures are required to make adjacent surfaces connect smoothly. To solve this problem, instead of parametric surfaces, subdivision surfaces are often used to represent shapes. However, how best to fulfill efficient modeling intended by designers is still problematic. On the other hand, smooth surfaces can be generated by interpolating a curved mesh with Gregory Patches. This method has the advantage that the G¹ continuity of adjacent surfaces can be maintained even if the curved mesh is modified. Here, we propose a modeling method that involves interpolating a curved mesh with Gregory Patches after generating a curved mesh of a Catmull-Clark subdivision surface. The shape difference between the generated surface and the subdivision surface is very small. One of the characteristics of our method is that if some vertices or edges are modified, only the surfaces connected to them are affected. Also, the surfaces wthin a specified area can be modified freely by keeping the continuity between them and the adjacent surfaces outside the specified area. The cutting and Boolean operations can be executed on the generated surfaces easily and our method can be applied to the polygon meshes generated by Boolean operations and that contain holes or bosses. In the modeling of free-form surfaces, a method that first generates a rough shape with a polygon mesh and then modifies its curved mesh to obtain the final shape is effective.

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The Awa Dance festival is one of the most famous traditional festivals in Tokushima Prefecture. Because the Awa-Odori dance is simple, beginners can easily learn the dance. However, it is very difficult to dance as beautifully as an expert dancer. An important factor in dancing the Awa-Odori dance beautifully is the motion of the hand and the arm. In this paper, the authors propose a method for evaluating the beauty of an Awa-Odori dancer's hand. As the first step in the proposed method, the motion of a dancer's hand was recorded in an image sequence using the optical flow. Next, four features effecting the beauty of the motion were calculated from the optical flow. Using this method, smoothness, energy, rhythm, and compactness were identified as four features. Finally, the four features are unified and the Awa-Odori dance is graded. This paper presents the findings of experiments conducted in order to verify the validity of the proposed method. Using this method, expert dancers received high scores while beginners received low scores.

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Aiming to realize “Single Source Multi-Use” of video content and the diffusion of HDTV materials to a diverse range of media, including networks and portable video devices, research has progressed on making HDTV program production more efficient through the application of JPEG2000 (JP2K for short) still picture coding scheme. By applying JP2K to HDTV moving pictures, the program contents production job with offline such as editing of HDTV material is not only streamlined with the scalability (hierarchical picture features) which is the feature of JP2K, it is also useful to transmission of live HDTV material because high picture quality of intra-field coding with low-delay can be actualized. Elementary technology research led to 1) the construction of a compact PC-based JPEG2000 HDTV Codec, 2) a software of Motion-JPEG2000 player and network client that allows simple screening of HDTV material on a general PC using the scalability of JP2K, and 3) a JPEG2000 UDP/multicast transmission protocol for HDTV material sharing in a networked program production environment for the first time in the world. The developments also included the construction of a prototype JP2K-HDTV program production system, which integrated the above-mentioned element technologies. We added uncompressed audio data transmission function that uses 24bits and 16 channels, and fabricated a JP2K emergency news reporting system for the relay transmission of live HDTV material from the news-gathering field over IP network with reduced transmission delay. A performance comparison was made between this new JP2K codec and the 140Mbps HDCAM-VTR (intra-Frame DCT), which is now widely used in the broadcasting field for HDTV materials, is confirmed that this new codec can yield a picture quality (SNR) equivalent to that of the HDCAM at 70Mbps, just half its rate.

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Embedding of the additional information on the various media can be used for judging if a certificate is forged or not. In this paper, we present a new method that is able to yield a less decoding complexity, keeping the sufficiently high level of security.

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[in Japanese]

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