Recently, several digital watermarking techniques have been proposed for hiding data in a frequency domain of image signals. However, in order to detect a watermarking sufficiently after heavy compression, the quality on an image might be visibly deteriorated by a digital watermarking with strong intensity. We have proposed a biometric authentication method for a digital image file using a discrete wavelet transform. The proposed method uses inherent information of an image for identification and never changes the image. The experimental results show that the proposed method has an excellent property on the tolerance to compression.
Some extensions to CSS font specification and related functionalities are proposed to satisfy user requirements provided by a conventional publisher and multimedia document creator. The proposed CSS properties can support a complicated composition on a paper and a new multimedia formatting on a display.
Multifunctional information equipment provides a number of functional properties that can have user specific values. Setting of user specific values, i.e. personalizing the equipment, requires more and more time as those properties increase. Interchange of the personalization information between equipments makes it possible to easily get a new personalized equipment. This paper shows the feasibility of interchanging personalization information of mobile phones and discusses standardization of the information.
In this paper, we propose a similar video sequence retrieval method based on spatio-temporal motion features: direction and velocity of the camera motion and the object motion. We enable the object extraction from the section including the camera motion by using its features. We use the spatio-temporal image processing for motion analysis. The spatio-temporal image processing enables us to eliminate small movements and extract motion features derived from major change. Then, we show that, by using these features, similar video sequences can be retrieved from movies.
In codec of motion pictures a good measure for evaluating the image quality including the color reproduction is strongly desired to determine a proper compression rate. In this article, we propose an image quality evaluation method for motion pictures compressed by H.264/AVC codec which is receiving increased attention. In the proposed method, we considered the contrast sensitivity function (CSF) of human visual system by the S-CIELAB filtering. Next, we quantified the amount of the movement of each content by using the correlation coefficient between frames of the motion pictures and incorporated it in image quality evaluation. As a result, we confirmed that the proposed method has high correlation with the subjective evaluation, and is superior to the other image quality evaluation methods.
The establishment of an objective evaluation method highly correlated with the subjective evaluation is desired for picture quality evaluation. We have proposed an objective evaluation method considering human visual characteristic such as the contrast sensitivity function and the masking effect. However, the performance of the proposed method, S-CIELAB, still remained comparable to conventional quality measures. Thus, we improved the proposed method by modifying the computation of the masking effect. The modified method showed better performance than the conventional evaluation measures.
The purpose of this paper is to propose a new approach to detecting obstacles using a single camera mounted on a vehicle when the vehicle is backing or turning round at an intersection at a low speed. Using restrictions among feature point locations and their optical flows in geometrically converted top-view images, ground-movement can be estimated. Our approach compensates for the ground movement between consecutive top-view images using the estimated ground-movement and computes the difference image between the previous compensated top-view image and the current top-view image. Finally, a new angle histogram-based algorithm is processed to extract obstacle regions using the difference image. The actual in-vehicle experimental results show that our proposed approach has tolerance for various changing illumination conditions and different road textures.
As for ultrasonic flaw detection of the axle and the pillar, the inspection by the reflection echo is done. The judgment from a wave pattern contains subjectivity, and the judgment is different in the beginner and the expert. As a technique for objectively judging it, I studied a method to make internal structure visible with an image reconstruction method. About the measurement method necessary for the image reconstruction, I measured a reconfiguration image by the change in the number of receiving sensors and the number of transmission places. As a result, I measured its examination body that had imitated the axle with the ultrasonic test equipment. I did the experiment that reconfigured the image was done by using the measurement data. By designing and producing the jig, I was able to measure the propagation path difficult to measured up to now. As a result, the accuracy of a image reconstruction improved, and the defect in the examination body was able to be detected. The same experiment was conducted by using the examination body that inserted a different metal, and the part where speed of sound was different in a image reconstruction was able to be judged.
Recently, a phased-array probe is widespread also in an industrial field. However, it is not suitable for the inspection to the depth. The WMR method is an algorithm of making to visible of an internal structure. It uses the wavelet function for the sampling function and the image is reconstructed from the travel time and the attenuation of the transmission ultrasonic between two probes. However, when the difference between the number of sampling points and the measurement data grows, the reconstruction becomes difficult. In this paper, a triangular sampling is applied, and the number of specimens is decreased so the difference with the number of measurement data is reduced. As a result, the singular value decomposition is made easy to solve, and the accuracy of the reconstruction is improved. In addition, it proposes the reconstruction method by the structure of layered dividing area reconstruction using the scaling property. The number of sampling points is reduced further by changing the sampling interval. The reconstruction accuracy and the processing time are evaluated by the simulation and the effectiveness is shown. Moreover, the detection of the population defect is evaluated from acquired data by using the developed counting system.
High resolution imaging with downsized pixels of an image sensor makes shortage of light exposure. To solve this problem, image processing such as super-resolution and motion-deblurring is available for higher resolution imaging. At this point, we review the state of the art of these techniques. After that, we show our proposed method for high resolution imaging in dark conditions.