[in Japanese]

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[in Japanese]

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[in Japanese]

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A signal interpolation method for chrominance moire reduction in images from a single-imager color video camera has been developed. This method (Correlative Coefficient Multiplying : CCM) interpolates one color signal using a second color signal multiplied by a correlation coefficient related to the ratio of low frequency components of the two color signals. It produces excellent quality video images with reduced chrominance moire and high resolution, reducing the harmonic component of the chrominance signal. An effective application of the CCM interpolation method is explained, and still images reproduced by the CCM interpolation from a color imager with normal complimentary filter are evaluated.

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A new measurement scheme for transfer characteristics using FM signals is proposed for the magnetic recording system of a VCR. The modulating signal of the FM signal is sinusoidal. The transfer characteristics are calculated from the complex frequency spectra of the FM signals before recording and after playback. A few cycles of an unmodulated FM carrier signal are added before the modulated FM signal as a phase reference signal. Several methods are introduced to reduce the influences of the phase reference point, jitter, and skew, and the transfer characteristics of an S-VHS VCR are measured. The experimental results show that the phase characteristic is approximately linear, and varies very little with the recording level. The amplitude characteristic is very nearly an odd function of the frequency centered at the carrier frequency, and it varies with the recording level, especially in the uppersideband.

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A neural network called a “Hierarchical Depth Perception System” is proposed in this paper for extracting the depth information from a stereo pair of images. Since isparity, i. e. difference between left image and right one, is assumed to be continuous everywhere in conventional methods which use competition and cooperation between neural units, they do not work well for images containing discontinuous disparities. We use a hierarchical system with the following features ; cooperation by the use of Perceptron, removal of isolated active nuits, cooperation and competition between units. In this system, some functions are activated at the positions with continuous disparities, and other ones are activated in other cases. The structure and functions of the system are described, and an application of the system to the depth perception of random dot stereograms is shown.

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The goal of our research is realistic teleconferencing. Generating images with motion parallax is a vital technology in improving human communication. To generate realistic images by Computer Graphics (CG), the number of vertexes of an object should be increased. However, to generate images with motion parallax, the images should be increased quickly. Thus, there is a tradeoff between generating highly realistic images and generating them quickly. In this paper, we evaluate the effect of the delay according to two parameters : the response time for generating images for head movement and the frequency of generating them. We also present a method to generate realistic CG images at high speed. The method is to select the image from a database of detailed models, each for a certain distance between the viewpoint and the object.

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This paper describes the sensitivity of the HARP (High-gain Avalanche Rushing amorphous Photoconductor) tube. The sensitivity is 80 times that of a conventional tube e.g. SATICON or PLUMBICON), due to the use of a thick amorphous Se layer (6 μm), and a target voltage of 676 V. The tube, called Super-HARP, produces a high picture quality that is unattainable with conventional ultra-high-sensitivify image devices. It has a high resolution (maximum horizontal resolution of more than 800 TV lines), a low lag (decay lag in the third field of 1.6%), negligible additional noise, and no FPN (Fixed Pattern Noise) or blooming.

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