We have been studying a flat image sensor consisting of a field emitter array (FEA) and a high-gain avalanche rushing amorphous photoconductor (HARP) film for compact ultrasensitive television cameras. We have fabricated and tested a 10-mm-thick VGA image sensor with an active-matrix FEA and HARP film whose maximum avalanche-multiplication factor is approximately 200. This sensor provides clear low-noise images of sufficient resolution and consumes little power under dim lighting conditions such as moonlight. It also prevents strong light from degrading the picture quality when it operates in high-sensitivity mode because the surplus charges due to the strong light are swept out by extra scanning within the horizontal blanking period. The sensor has potential as a part of practical compact ultrasensitive TV camera that can be used not only for broadcasting but also in various fields such as science, medical diagnostics, and security.

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Super Hi-Vision is a ultra high definition video system toward a future TV service. Picture quality, picture characteristics and recent research activities are described. Capturing and displaying devices with Super Hi-Vision full resolution are developed in 2008.

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Computer input system with line-of-sight vector estimation with a simplified calibration is proposed together with the system without calibration for utilizing it as a keyboard for the wearable computing and for communication device for disabled persons and elder persons who are not familiar with computer input with keyboard. The system utilizes employs a commercially available and relatively cheap web camera, a display and an indirect light source so that it is easy to equip and also easy to use. Calibration accuracy is one of largest key factors for such this computer input system based on a line-of-sight vector estimation with morphologic filter after detection of human eye. The proposed system requires just two keys calibration. This paper also proposes another modified system which does not require any calibration at all. Through experiments, it is found that the success rate depends on the number of keys for calibration. Also it is found that success rate of the proposed system with two keys calibration is almost 99.8% and that of the modified system without any calibration is 100%.

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We studied the method to automatically extract nucleated red blood cells (NRBCs) from massive microscopy images of mother's blood. In this research, the nucleated red blood cells and other cells can be distinguished based on features of the area size, shape, and the color, etc. By limiting the area as much as possible, the speed-up of the cell extraction processing was achieved in spite of a large amount of image being analyzed. The detection rate of NRBCs has improved more than visual detection, and the detection of false positive cells (neutrophils, lymphocytes and red blood cells with debris) has decreased.

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We generate an image with many lighting equipments by fusing images with a few lighting equipments. It is difficult to generate the image by using the traditional fusion method. We introduce the image fusion space describing the neighbor relation between the traditional fusion methods. We propose the method selecting the fusion method for the each pixel from the image fusion space. At first, we get the intensity, hue, saturation images using HSI images and the activity level is defined using the intensity image. The image is divided into small regions using the histogram, and is identified whether the back light or the front light. The fusion image is defined using the parameter in the divided regions. We show the effectiveness by generating the fusion images with lighting in the general environment.

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This paper proposes a new approach for precisely and stably detecting changes in image scaling factor. DFT amplitudes for reference and input images are first transformed to the polar expressions. In the transformation, the cause of detection errors is analyzed and optimal frequency filtering for reducing errors is found. The position shift between the polar spectra is detected by our PSA method. The weight function effective for accurate detection of the shift is discussed. The approach is applied for detecting changes in image scaling factors for four typical types of images. It becomes clear that the scaling factor can be detected with higher accuracy by the proposed approach than by the conventional method. The accuracy dependences on the image pattern and scaling factor are also made clear and discussed.

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Electronic holography, which fulfills all 3D perceptual cues, seems an ideal method to provide visual information for ultra-realistic communication, which aims realization of an environment as if immersed in the presented scene. However, as the electronic holography requires huge data, high quality hologram generation and its reproduction have several problems. In this paper, an approach is investigated adopting hologram generation from 2D image with depth map, aiming to reduce the data amount, analyzing and compensating astigmatism and color aberration, which are caused by the optical elements, and integrating phantom effect elimination in the hologram calculation, which prevents an artifact where background objects are observed through foreground objects.

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In this paper, a transmitting process of a sequence of holograms describing 3D moving objects over the communicating wireless-network system is presented. If a sequence of holograms is transformed into a bit stream of data under some properly adjusted encoding conditions, it is found that the sequence of hologram can be fully transmittable over the wireless network. It is shown that applying this technique, holographic data of 3D moving object is transmitted in high quality and a relatively good reconstruction of holographic images is performed.

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This paper proposes a novel data hiding method in the MPEG domain in which the image quality of the modified video is completely preserved to that of the original (compressed) video. To the best of our knowledge, there is no data hiding method that completely preserves the video quality during data embedding, and this method is the first attempt of its kind. This method is reversible where the modifications done during data embedding could be undone to restore the original video. This method is applicable not only to existing MPEG1/2 encoded videos but also to the encoding process of MPEG video from a sequence of raw pictures. The Reverse Zerorun Length (RZL) data representation scheme is proposed to exploit the statistics of macroblocks for achieving high embedding efficiency while trading off with payload. We theoretically analyze that RZL outperforms matrix encoding for both payload and embedding efficiency for this particular data hiding method. The problem of filesize increase during data embedding is addressed, and two independent solutions are proposed to suppress the filesize increase. Basic performance of this method is verified through experiments on various existing MPEG1 encoded videos.

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Multiple description video coding which composes multiple-quantization operations at decoder for PSNR improvement, maintaining conventional coding algorithm such as MPEG-4 visual, is proposed. The proposed method is applicable to video transmission over integrated wireless services comprising multiple wireless-access networks such as wireless LAN and cellular networks. Quantized DCT coefficients of the same block quantized using different quantization parameters are in general different. The proposed method narrows down DCT coefficient value (true value) before quantization, and operates quantization parameter in order to utilize the DCT coefficient value narrowed. MPEG-4 visual based simulation demonstrates 0.5-1.0dB PSNR decoder gain of the proposed method.

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We analyzed the influence of bitrate of video and audio on realistic sensation, and try to estimate the realistic sensation from bitrate. Firstly, we conducted the subjective assessment by the SD method, and factor analized in order to compress the evaluation space. As a result, three kinds of factors were obtained. Secondly, we conduced similary the subjective realistic sensation score. Moreover, the multiple linear regression analysis was conducted with the realistic sensation and the three scores. Therfore, the realistic sensation was able to estimate with sufficient accuracy by the three scores. Thirdly, we conduced multiple linear regression analysis by the two scores and bitrate, since out of all three factors' scores, two scores correlated with bitrate of video and audio. Consequently, the two scores were able to estimate by bitrate with good accuracy. Therefore, it turned out that bitrate of video and audio influences the realistic sensations, and was confirmed that realistic sensation could be estimated from bitrate of video and audio.

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Displays tends to expand its color gamut, such as multi-primary color display, Adobe RGB and so on. It is now possible to design computer graphics using previously unavailable colors. However the environment for contents production is not yet established. In order to using wide color gamut effectively, we have developed contents production systems and prototype graphic software with six primary color display. And we have developed a user interface for mixing the six primary colors easily. Through creating wide color gamut contents with systems that we developed, we confirmed the effectiveness of our systems and contents. In addition, we have researched the psychological effects of viewing an extended range of colors.

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The main subject of this paper is to shift color of the reconstructed image because we can get different impression by the color of hologram image. We used the pre-swelling emulsion process to get large color shift and consider about the quantitative analysis about the change of color shift. Also we consider about the reconstructed image color tone using swell process.

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Partitioned Iterated Function System (PIFS) compresses images by partitioning image into block and searching contraction mappings among the blocks. PIFS is based on Recurrent IFS (RIFS). Each pixel in the image can be assigned to IFS addresses using IFS address theory. Barnsley proposed Color-Stealing Algorithm (CSA) that picks up a color value on an arbitrary image, and transfers it to another images to render them with fractal flavor mapping two IFS addresses. Barnsley uses IFSs which have four maps as Drawing and Stealing IFS. In this case, it is difficult to find an appropriate IFS to draw. In the present papar, we use PIFS to encode an image and assign appropriate addresses to each pixel, and use CSA to transfer colors from one image to another with fractal flavor.

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In order to find an efficient lossy coding scheme of ordered dither images, two different coding categories, multi-level lossy image coding (LML) with post-processing of ordered dithering, and sending the number of black pixels in a block of bi-level pixels (BPN), are proposed and studied. Among the former category, we adopted JPEG2000 as the best one, and for the latter category, we assumed the context based coding, which refers to the numbers of black pixels in several neighboring blocks. By setting same bit rate per pixel for these two methods, the picture quality of the restored lossy bi-level images were evaluated using the PSNR of inverse halftoned images. It was found that to use the inverse halftoned (IH) image of lossless bi-level one as the reference image in calculating the PSNR will be better than to use the original multi-level image in reflecting the subjective picture quality, and that BPN has better performance than LML for higher bit rate and LML will catch up BPN as the bit rate decreases.

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This paper presents an industrial application of a new type of graphic technique based on dual two-dimensional optical system and video image analysis. The technique has been intensively developed for optical fiber industry for preform inspection held beforehand fiber drawing. The optical system uses a pair of LCD and CCD video camera both as two-dimensional detector and as two-dimensional light source, respectively, to achieve dual two-dimensional co-ordinations required in its principle. For corresponding to various type of fiber preforms, we can choose suitable method from some variations of measurement technique which each uses different type of pattern on LCD and its virtual movement. The CCD image is numerically processed and refractive index distribution in the sample preform is finally reconstructed for assessment of fiber quality. The equipments based on the method have been practically constructed and the principles are successfully confirmed by experiments.

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We propose a tracking method via 1D flow. This method is based on voting of the positive 1D flow and updating the several calculation axes depending on the voting result. The characteristics of this method are avoidance of ill-posedness by 1D flow, and expansion of the traceable motion by spanning the several calculation axes. Moreover, we introduce a scheme which can track a object changing the motion sharply. The experimental results show the possibility of tracking by 1D flow even if the object changes the motion sharply.

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When taken outdoor, color information of pictures changes greatly depending on environmental changes, setting of digital camera, and so on. For the purpose of growth diagnosis of agricultural crops by using image communication, it is important to assure accurate display of color. This research proposes a high accurate and automatic color correction methods in a part of the uniform color space, using color chart in a specific color area currently used to judge growing state of agricultural crops. It will help perform adequate growth diagnosis by using image communication. As a result, it was confirmed that the proposed methods can correct the colors in a specific color area and the diagnosis accuracy can be improved.

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