In the presentation of 3D holographic images, spatial projection technique with the use of mist screen seems to be very effective. In this paper, as an improved technique to produce more stable reconstructed images with smaller fluctuation level, we proposed a projecting technique for reconstructing holographic 3D images on the mist screen employed thin soap bubble film. It suggests that more stable projected 3D images are observed with full parallax than by previous techniques employed mist screen, although there is some time-limitation in the observation of the reconstructed images.

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Stable electro-holography which can be projected in the space freely seems to be expected. We have studied several projecting methods adopting waterfall screen made of liquid form of the water particles mixed with the small ones of impurities to present holographic 3D images. In this paper, as an improved technique to produce more stable reconstructed images, we proposed a holographic 3D display system employed water-fall screen equipped with viscous medium (polysaccharide). It suggests that by introducing our method, a more stable waterfall screen is possible than before, and it may reduce the fluctuations in the projected images more effectively.

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An interpolation method using a polyharmonic function enables the smooth interpolation of a plane using arbitrary boundary shapes and arbitrary points inside the plane. We have proposed a method for enlarging images smoothly by applying the interpolation method to image processing, assuming that the images are curved planes, and already confirmed its feasibility. With the image processing method we have proposed, images are interpolated using the pixel information of the entire image, which requires a huge amount of calculation when the size of the target image is large. The central processing unit (CPU) of recent general-purpose personal computers has a multicore design, and any user can carry out parallel processing without difficulty. Considering these factors, in this study, we proposed a concrete segmented processing method for parallel processing of image enlargement by the interpolation method using the polyharmonic function without deteriorating the quality of the images after processing. Parallel processing was carried out by the proposed method using open multiprocessing (OpenMP)-based tools that we can use easily. The results indicate that the time required for image processing can be substantially reduced by our proposed method.

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Template matching is an effective method for calculating the similarity of the corresponding positions between images. However, a mismatch may occur due to occlusions, shadows, or distortions. This paper shows that there is an optimal template shape based on the residual probability distribution function obtained from the searched image and proposes a method for automatically creating the optimal template shape. Moreover, this paper also presents the results of a study on the techniques used to maintain the diversity of each individual body when applying a genetic algorithm on a template. In order to evaluate the effectiveness of the proposed method, 5 different types of images are used for comparison with other three methods. In the experiments, the proposed method gave the best results compared to the other 3 methods, showing its high level of usefulness.

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Low cost, portability, high-speed print is required to mobile printer. In this paper, we focus on optical printing system capable of low power consumption and high-speed printing and consider applying low-cost TN liquid crystal shutter to print-head. We investigate TN liquid crystal shutter’s optical properties requirements and optimum structure suitable for a print head of mobile printer. Reducing the cell gap is effective to improve optical response of TN liquid crystal shutter. Voltage application time for stabilizing optical response of TN liquid crystal shutter can be approximated by a negative power function of applied voltage. Electrode masks and light shielding masks are made in gold film at the same time. The thickness of the gold film is required more than 0.28 micrometer. Those are suitable as structural economic of TN liquid crystal shutter. Results of experiments with the prototype print head shows that printed quality is equivalent to the conventional print head, and it can be printed in 10 seconds.

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In a mass screening for gastric cancer, diagnosticians read many stomach X-ray pictures at a time. To decrease the number of reading the pictures in the mass screenings, the proposed method discriminates normal cases in stomach X-ray images using the propposed features. In normal cases, folds on the stomach wall appear in parallel in the images. Therefore, the proposed method measures characteristics of parallelism for the folds in the images. Experimental results of the discriminations for 103 images have shown that the proposed features are well effective for recognizing normal cases.

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Early detection of diabetic retinopathy (DR) is important because it may cause visual loss. In this paper, we propose an automatic detection technique of microaneurysms (MAs) which are early signs of DR from retinal fundus images by density gradient vector concentration. After image preprocessing, the density gradient vector concentration was calculated in green-channel component and MA candidates were detected by adaptive thresholding. Forty eight features based on texture analysis, pixel value, and shape were calculated from each candidate and the candidates were classified into MAs or false positives by thresholding and a support vector machine. The average sensitivity at selected false positive rates by the proposed method was 0.395 in the evaluation with ROC (Retinopathy Online Challenge) database. The proposed method may be useful in automatic MA detection.

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In this paper, we propose an efficient method for re-estimating a human pose by applying constraints to a tree-structured Pictorial Structure (PS) model in pose estimation. The PS model is not robust to double-counting and disturbing textures such as background, hence our proposed method consists of the following two key ideas. (1) Applying an appearance constraint using the similarity of color distribution for a pair of symmetric parts to be robust against background. Then, if the pair of symmetric parts is estimated as a same position, the likelihood of the constraint is higher, and the constraint leads to the double-counting problem, and so an auxiliary constraint based on distance of the symmetric parts is applied. (2) To suppress unnatural incorrect pose estimation by using constraint based on human natural poses as prior knowledge. Here, clusters that represent various kinds of poses are used; however, the attribution cluster of a test image is obtained from a single PS model to reduce the computational cost. In the experiment, the proposed method reaches up to 80% in Percentage of Correct Parts (PCP), which outperforms the conventional PS models. In addition, the computation time of the proposed method is 1.25 times than the original PS model. Besides, the proposed method is a high speed and performance compared with the other improved method.

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In this paper, I propose an image inpainting technique for damaged oil painting that aims to create their restored examples. Usually, image inpainting technique has the advantage of being able to work well for a wide variety of images because it does not require any information about target images. However, image inpainting has the potential to work more effectively if it limits the targets and introduces the processing based on property of oil painting. Proposed method achieves high performance for oil painting images by introducing two processing based on property of them. One is to apply smoothing filter based on painting technique, and the other is to add asperity of painting as texture.

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This paper proposes a fluid simulation method with a surface tension effect using interparticle interaction forces based on a position based fluid. Behavior of fluid is efficiently calculated by using SPH (Smoothed Particle Hydrodynamics), which represents fluid as particles, and the method appends the surface tension force as the interaction force between the particles. Also, interaction between fluid and solid boundary is considered by adding solid particles along the boundary. Furthermore, this paper propose an instinctive controlling method for liquid shape, such as a water drop, by using a contact angle.

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The optimum frequency band partition which divides the 2-dimensional frequency domain into an adequate set of subbands based on the stochastic characteristics of the input image has been developed in subband image coding. In this paper, a hybrid optimum frequency band partition method which can determine an unique partition pattern by integrating two kinds of partition patterns in the conventional methods is proposed with small computational costs, in order to improve the coding efficiency of the subband image coding.

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We discuss a spatially projecting process for holographic images with the use of the mist screen of water particles. In this paper, we studied a process to expand the viewing angle of the projected images by new optical reconstructing system. It employs several mirrors to combine the reconstructing waves reflected from only one spatial light modulator(SLM). As this result, by using our system, projected images can be observed with wilder viewing angle. In addition, we propose a process to extend the number of the displaying surfaces so that the images can be observed at the same time by more than one person.

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Previous work on virtual object manipulation by a real object in an augmented reality (AR) environment mainly focuses on a rigid object as the real object. If a human hand is considered as the real object, direct manipulation of virtual objects by the real human hand is realized. For virtual object manipulation by a human hand, its position and posture in the real environment need to be obtained. However, measurements of those position and posture often include some errors regardless of the measuring method. Moreover, the user often fails to grasp a virtual object properly even by his/her own hand especially when no haptic feedback is given. As the result, a non-negligible amount of geometric gap occurs between the human hand and the virtual object. In this article, we propose to replace the human hand with a virtual hand given by CG in an AR environment based on a video see-through display so that the position and the posture of the hand can be modified, while keeping the consistency between the virtual hand and the rest of the human body appearing in the AR environment by making their positions coincide with each other at the wrist.

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