Piecewise linear two-dimensional warping (PL2DW) is a practical elastic image matching technique where the pixel-to-pixel correspondence function between a pair of image patterns is defined as a piecewise linear 2D-2D mapping. For accurate matching, the boundary points of linearization, called “pivots”, should be placed at the bending and stretching points of image patterns. In conventional PL2DW, it is assumed that the pivots are properly placed by users before their mapping is optimized. This assumption, however, is acceptable only when the a priori knowledge about the deformation characteristics of the image patterns is available. In this paper. an improved PL2DW technique is proposed. In this technique, along with the mapping of pivots, their placement is simultaneously optimized. As a result, pivots are placed automatically at the bending and stretching points of the target and therefore accurate matching is obtained without any a priori knowledge.
Virtual cameras need real-time controls to enable navigating in virtual space, but conventional input devices, such as a mouse, cannot produce flexible interfaces to intuitively control virtual cameras in such a way as to create an impression of actually walking through the virtual space. Therefore, we developed an automatic navigation technique that takes into account the geometrical structure and visual attributes of exhibitions. A guide agent is introduced to control the camera in order to effectively browse the exhibitions while imitating natural human behavior.
One-dimensional reproduced images have been improved to include frequency components higher than the Nyquist frequency. To reduce the noise in reproduced images, which is caused by the positional shift between two input images, the precision of the relative position between the images was increased by developing new equipment and an image spatial shifting program by using a Fourier transform. The quality of reproduced image was there by improved, and frequency components 1.5 times as high as the Nyquist frequency were reproduced.