Mingmin Zhang

Watermark extraction by magnifying noise and applying global minimum decoder

For the classical watermark embedment model I = 1 + /spl alpha/W, the corresponding watermark detection has its limitation in its need of a fixed parameter for extracting watermarks. If the extraction parameter is too large, we cannot extract the watermark from the image that contains watermarks; if it is too small, the extracted watermarks may be blurred. This paper proposes a novel watermark extraction method. First, we treat the watermark information as noise for the watermarked image in its spatial domain. We then magnify the noise before detection. Next, we recover the watermark information by adjusting the extracted data from the frequency domain according to our global minimum method. Experimental results show that our watermark extraction method is more valid and accurate than the classical method. It can greatly reduce extraction errors.

VisBubbles: a workflow-driven framework for scientific data analysis of time-varying biological datasets

Our long-term collaborations with bat flight biologists have revealed that several workflow issues continue to be persistent barriers in scientists data analysis tasks. Only limited attention has been given to user interfaces that bridge programming and visualization in environments involving multiple information resources, feature extraction by programming, and analytic study. We present VisBubbles (Fig. 1), a unified environment supporting programming, visualization, and interaction concurrently for data analysis workflow. The framework was developed in a participatory design process and discussion with biologists continues to provide new insights into general-purpose support for data-analysis workflow.

Watermarking subdivision surfaces based on addition property of Fourier transform

This paper presents a private subdivision surface watermarking algorithm. The subdivision schemes include Doo-Sabin Subdivision and Loop Subdivision. The subdivision surface watermarking algorithm includes three main steps as followings. First, the resultant watermarked image minus the original image is the watermark information. The image watermarking algorithm is based on the Fourier transform. Then, the watermark information is scaled down and embedded in one part of the x-coordinate of the subdivision surface. So, the watermarked subdivision surface is obtained. Finally, the x-coordinate of the test subdivision surface is amplified for more effective recovery of watermarks during extraction with original subdivision surface according to the addition property of the Fourier transform. Experimental results prove that our algorithm is resistant to some attacks including noise addition, cropping, rotation, translation, scaling and filter.

New texture morphing method for visual presentation of textile product

Textile emulation is a key problem in the visual textile presentation. In this paper, we present a new algorithm to achieve the realistic feeling of textile. This algorithm first divides the target area into some texture blocks that have different texture directions. Then morphs the texture coordinate of each texture block. The calculating speed of this algorithm is very fast, so it is more suitable for the visual textile presentation of e-commence.

Multi-stroke freehand text entry method using OpenVG and its application on mobile devices

A new freehand text entry method, called EasyStroke, is presented for mobile devices. Based on the multi-stroke philosophy and analogy principle, 26 lowercase characters are described. Trails of stylus movement are segmented dynamically and best approximated through the three captured points. Then, each segment is rendered immediately using hardware-accelerated OpenVG APIs. Finally, combination of the types of all segments flows into the small LUT-based recognizer, using some additional bits. Thus, this new method is easy, efficient and quick to use. Implementation and evaluation of such system are presented. Prototype of mobile game, WordCollection, is demonstrated to help users experience functions of both education and entertainment.

An illumination distribution preserved colour substitution algorithm based on dichromatic reflection model

In this paper, we introduce a novel colour substitution algorithm based on the dichromatic reflection model. We separate the object colour and scene illumination information in the target area of the original image. The object colour was subsequently substituted while keeping the illumination information unchanged. A new method was employed to estimate the object colour. We also developed a set of new parameters to adjust the intensity distribution on the resultant image. Our algorithm is totally automatic and can achieve more realistic effects compared with other colour substitution methods.

Heart-Creates-Worlds: An Aesthetic Driven Fitness Training System

We present a novel fitness training system called Heart-Creates-Worlds (HCW) as a practical while pervasive solution to encourage effective daily physical activity. In this system, the aesthetic audiovisual effects of a virtual world are tightly associated with the user’s real time heart rate, while the heart rate reflects the users’ physiological and psychological state accordingly. By physically act on the control of the representation of the virtual world, users are being persuaded into traveling in a more aesthetically pleasing virtual surroundings than in the displeasure one, meanwhile, naturally fix themselves at the target fitness training zone. A pilot user study was conduct to evaluate the effectiveness and enjoyment of HCW. The results indicate that, this kind of aesthetic-driven fitness training system is helpful on encouraging regular physical performance with enough amounts.

Aesthetic-driven interaction: a pleasurable persuasive technology for health behavior change

Regular physical activities play a key role in a persons body shape and health improvement. It is challenging to encourage the public to meet the target (intensity, duration, frequency, etc.) and reap the benefits. Many theory-based persuasive technologies, such as Goal-Setting Theory and the Transtheoretical Model of Behavior Change, are often applied to encourage health behavior change. However, little consideration has been given to dealing with the issue of pain - the effort and other unpleasant sensations during physical activities which have a negative influence on performance tolerance and behavioral decisions.

HumMod explorer: a multi-scale time-varying human modeling navigator

HumMod [Hester et al. 2011] models interactions between the cardiovascular, respiratory, renal, neural, endocrine, skeletal muscle, and metabolic physiologies. One of the difficulties which must be overcome with HumMod is the fact that the number of parameters is prohibitive in developing a clear and comprehensive view of the interactions between parameters. Currently the HumMod model contains more than 5000 variables. Therefore, good visualization techniques are needed to discern non-obvious relationships between variables. We present HumMod Navigator, a multiple-scale physiology data browser for exploring casual relationships of time-varying human modeling data. The visualization makes use of a circular layout and hierarchical relations to effectively visualize interactions between model parameters in an attempt to obtain both a local and comprehensive view of the physiological modeling environment.

A Collaborative Aesthetic-Driven Virtual Fitness Game

By introducing a collaborative aesthetic-driven virtual fitness game, we give a possible solution to guide and encourage people who have sedentary lifestyle to do regular physical activity with enough intensity, duration and frequency. This method bridges physical interaction with a stationary bicycle and visual changes in a virtual environment, and combines it with a multiplayer game. During the test of game playing, individual participant’s effort to meet their own target heart rate zone contributes to a team effort of aesthetic immersion overall.