Lan-Rong Dung - Academia.edu (original) (raw)

Papers by Lan-Rong Dung

Journal of Information Science and Engineering, Jul 1, 2006

This paper presents a novel power-aware motion estimation architecture for battery-powered multim... more This paper presents a novel power-aware motion estimation architecture for battery-powered multimedia devices. As the battery status changes, the proposed architecture adaptively performs graceful tradeoffs between power consumption and compression quality. The tradeoffs are considered to be graceful in that the proposed architecture is scalable with changing conditions and the compression quality is slightly degraded as the available energy is depleted. The key to such tradeoffs lies in a content-based subsample algorithm, first proposed in this paper. As the available energy decreases, the algorithm raises the subsample rate for maximizing the battery lifetime. Differently from the existing subsample algorithms, the content-based algorithm first extracts edge pixels from a macro-block and then subsamples the remaining low-frequency part. By doing so, we can alleviate the aliasing problem and, thus, limit the quality degradation as the subsample rate increases. Given a power consumption mode, the proposed architecture first performs edge extraction to generate a turn-off mask and then uses the turn-off mask to reduce the switch activities of processing elements (PEs) in a semi-systolic array. The reduction of switch activities results in significant power consumption savings. To achieve a high degree of scalability and qualified power-awareness, we use an adaptive control mechanism to set the threshold value for edge determination and make the reduction of switch activities rather stationary. As shown by experimental results, the architecture can dynamically operate in different power consumption modes with little quality degradation according to the remaining capacity of the battery pack while the power overhead of edge extraction is kept under 0.8%

HCI International 2018 – Posters' Extended Abstracts, 2018

This paper presents a gaze estimation algorithm using integral projection of eye images with adva... more This paper presents a gaze estimation algorithm using integral projection of eye images with advantage of low additional hardware requirement and low computational power. The algorithm needs only a webcam under nature light source and captured eye images in a non-intrusive way. Before integral projection, we used binarization process to eliminate the non-related image information to gaze position. Projected on binary eye images with projection adjustment method to avoid eye tilt makes projection error and defined the accurate integral range of eye ROI images to achieve robust gaze estimation. We analyzed the projection diagram with skewness to describe the variation of different gaze position. In skewness calculation, the pixel coordinate of eye ROI images has been normalized to avoid head moved back and forth makes the size of ROI changed. In horizontal direction, the error angle of our algorithm is 2.29°, maximum error angle is 4.8° and the resolution we defined is 7.5. Because our algorithm is inaccurate in vertical, we could only estimate gaze direction, but to estimate precise angle. The computational power of our algorithm is low, the average execution time of each frame is only 0.01652 s, only 24% of opponent.

Journal of Signal and Information Processing, 2018

This paper proposes an object-tracking algorithm with multiple randomlygenerated features. We mai... more This paper proposes an object-tracking algorithm with multiple randomlygenerated features. We mainly improve the tracking performance which is sometimes good and sometimes bad in compressive tracking. In compressive tracking, the image features are generated by random projection. The resulting image features are affected by the random numbers so that the results of each execution are different. If the obvious features of the target are not captured, the tracker is likely to fail. Therefore the tracking results are inconsistent for each execution. The proposed algorithm uses a number of different image features to track, and chooses the best tracking result by measuring the similarity with the target model. It reduces the chances to determine the target location by the poor image features. In this paper, we use the Bhattacharyya coefficient to choose the best tracking result. The experimental results show that the proposed tracking algorithm can greatly reduce the tracking errors. The best performance improvements in terms of center location error, bounding box overlap ratio and success rate are from 63.62 pixels to 15.45 pixels, from 31.75% to 64.48% and from 38.51% to 82.58%, respectively.

Journal of Computer and Communications, 2018

This paper aims to speed up a segmentation algorithm "Grab Cut" by separating the process of segm... more This paper aims to speed up a segmentation algorithm "Grab Cut" by separating the process of segmentation into hierarchical steps. The Grab Cut algorithm segments images by means of the color clustering concept and the process requires a lot of iteration for it to get converged. Therefore, it is a time-consuming process which we are interested in improving this process. In this study, we adopt the idea of hierarchical processing. The first step is to compute at low resolution to make the iteration much faster, and the second step use the result of the first step to carry on iteration at original resolution so that the total execution time can be reduced. Specifically speaking, segmentation of a low resolution image will lead to high-speed and similar-segmentation result to the segmentation at original resolution. Hence, once the iterations at low resolution have converged, we can utilize the parameters of segmentation result to initialize the next segmentation on original resolution. This way, the number of iteration of segmentation at original resolution will be reduced through the initialization of those parameters. Since the execution time of low resolution images is relatively short, the total hierarchical execution time will be reduced consequently. Also, we made a comparison among the four methods of reduction on image resolution. Finally, we found that reducing the number of basins by "Median Filter" resulted in best segmentation speed.

Optical Engineering, 2012

This study investigates image processing using the radial imaging capsule endoscope (RICE) system... more This study investigates image processing using the radial imaging capsule endoscope (RICE) system. First, an experimental environment is established in which a simulated object has a shape that is similar to a cylinder, such that a triaxial platform can be used to push the RICE into the sample and capture radial images. Then four algorithms (mean absolute error, mean square error, Pearson correlation coefficient, and deformation processing) are used to stitch the images together. The Pearson correlation coefficient method is the most effective algorithm because it yields the highest peak signal-to-noise ratio, higher than 80.69 compared to the original image. Furthermore, a living animal experiment is carried out. Finally, the Pearson correlation coefficient method and vector deformation processing are used to stitch the images that were captured in the living animal experiment. This method is very attractive because unlike the other methods, in which two lenses are required to reconstruct the geometrical image, RICE uses only one lens and one mirror.

Ieice Transactions on Fundamentals of Electronics Communications and Computer, 2005

2014 IEEE International Conference on Internet of Things(iThings), and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom), 2014

This panel discussion aims at exploring the potential applications of emerging natural user inter... more This panel discussion aims at exploring the potential applications of emerging natural user interface (NUI) technologies and the challenges they pose to the design and deployment of cyber-physical systems. Based on their research work, six panelists will take turns to present the outlook, the cyber-physical requirements and the promising applications of implicit NUI. We hope these short presentations will lead to thought-provoking discussions and inspire further innovation.

Communications in Computer and Information Science, 2015

In recent years, the visual object tracking has drawn increasing interests. There are many applic... more In recent years, the visual object tracking has drawn increasing interests. There are many applications, e.g., video surveillance in airports, schools, hospitals and traffic. The object surveillance may provide crucial information about the behavior, interaction, and relationship between objects of interest. This paper addresses issues in object tracking where videos contain complex scenarios. We propose an adaptive particle filters tracking scheme with exquisite resampling (AERPF), which improves prediction, importance sampling and resampling. In prediction step, an adaptive strategy for search region and particle number is addressed for object disappearing or obstacle disturbance, which can obtain results more effectively. In addition, in importance sampling, we use optical flow to refine the particle weights using the dynamical object motion information, which results the better accuracy of object location updating. Moreover, exquisite resampling (ER) algorithm can be applied for reflecting more the posterior probability density function of true state. The proposed method can be applied for object tracking both on fixed and active camera, handling partial occlusion and full occlusion problem properly. As a result, it outperforms other existing methods.

Proceedings of the 2005 conference on Asia South Pacific design automation - ASP-DAC '05, 2005

This paper presents a multiple-voltage high-level synthesis methodology for low power DSP applica... more This paper presents a multiple-voltage high-level synthesis methodology for low power DSP applications using algorithmic transformation techniques. Our approach is motivated by maximization of task mobilities in that the increase of mobilities may raise the possibility of assigning tasks to low-voltage components. The mobility means the ability to schedule the starting time of a task. It is defined as the

2007 IEEE International Symposium on Industrial Electronics, 2007

The lithium-ion (Li-ion) battery is a time-varying, nonlinear component. Its discharge characteri... more The lithium-ion (Li-ion) battery is a time-varying, nonlinear component. Its discharge characteristic is dependent on discharge current, loading change scheme, ambient temperature, and initial state-of-charge (SoC), and hence its remaining time can vary with the discharge operating conditions in a manner of nonlinear relationship. The non-linearity behavior makes the accurate gas-gauge of Li-ion battery very difficult. This paper presents an efficient scheme to simplify the estimation of battery service time with high-degree of accuracy. According to the typical discharge characteristic of Li-ion batteries, we applied a two-phase single-time-constant (STC) model for the gas-gauging strategy and parameterize the discharge operating conditions in terms of the first-phase gradient, the knee voltage, and the second-phase gradient, instead of using complex curve-fitting equations. As shown in the experimental results, the accuracy of predicted remaining time is less than 1% for constant current cases, and 10% for loading change cases.

2007 IEEE Biomedical Circuits and Systems Conference, 2007

This paper proposes an efficient framework of high-quality image compression method for upper Gas... more This paper proposes an efficient framework of high-quality image compression method for upper Gastrointestinal tract endoscopy images. The proposed DEWC coding method saves traditional image preprocessing computations, such as demosaicking and color-space transformation, and directly utilizes raw image data acquired from CMOS sensor. R, G and B band image are then separately encoded by wavelet-based SPECK coding. In a cardinal GI tract environment, the spatial frequency distribution of red component is lower than green or blue, and green component is relatively high while compared to blue and red components. DEWC coding saves more bits on red band while allocating more bits on green and blue bands. Therefore, under a fixed compression ratio, such non-uniform bit-rate allocation may earn a better image quality. To measure quality-loss in non-uniform bit-rate allocation, a quality quantified measurement called color-distortion based on CIE94 color-difference formula is also proposed. By using analytical result of color-distortion in bit-rate and bit-rate-difference analysis, an optimal/suboptimal bit-rate allocation scheme can be found by solving linear equations derived from the relationship of color-distortion and bit-rate-difference. When comparing to general JPEG2000 compression standard, the experimental result shows that proposed DEWC coding has a better image quality in color-distortion measurement and more efficient performance in execution time.

3rd International Symposium on Image and Signal Processing and Analysis, 2003. ISPA 2003. Proceedings of the

This paper presents a novel power-aware architecture, called the vario-power architecture, for mo... more This paper presents a novel power-aware architecture, called the vario-power architecture, for motion estimation. Based on the proposed content-based subsample algorithm, the architecture can operate at different power consumption modes with little quality degradation and the switching of power mode can be done dynamically. As shown in the simulation results, the power consumption can be significantly reduced by simply change

Journal of Neuroscience and Neuroengineering, 2012

VLSI Signal Processing, IX

The paper describes how rapid model-year architectural synthesis (e.g., HW/SW codesign) of embedd... more The paper describes how rapid model-year architectural synthesis (e.g., HW/SW codesign) of embedded signal processors can be performed to optimize various cost objective functions using a reuse library of model, followed by simulation based optimization. Sponsored as part of DARPA&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s RASSP program, this approach has developed and released a number of interoperable and verified architectural component libraries at the system

2011 International Conference on Consumer Electronics, Communications and Networks (CECNet), 2011

A varying current charger for rechargeable Lithium-ion battery is implemented to maintain a prede... more A varying current charger for rechargeable Lithium-ion battery is implemented to maintain a predefined energy bound which is consumed by the overpotential equivalent resistance. For aged Lithium-ion batteries, the traditional CCCV charging method charges the battery with the same constant current no matter how the battery internal overpotential resistance increases. The varying current charger developed in this paper will follow the pre-defined energy bound, calculate the internal resistance from EMF and update the next charge current by matching the estimated time to consume the energy bound and the end of charge time. The hardware prototype is implemented with a FPGA and a current source board and the communicates with PC user interface through UART. The experiments show that the efficiency for the varying charge current method is hold for both a new battery and an aged battery although the charging time is compromised.

2008 IEEE Biomedical Circuits and Systems Conference, 2008

The objective of this paper is to develop an ultra-low-power video compression processor for caps... more The objective of this paper is to develop an ultra-low-power video compression processor for capsule endoscope to lower the RF transmitter bandwidth. In applications of capsule endoscope, it is imperative to consider battery life and performance trade-offs. Applying state-of-the-art video compression techniques may significantly reduce the image bit rate by their high compression ratio, but they all require intensive computation

2013 IEEE International Conference on Acoustics, Speech and Signal Processing, 2013

Touching devices have become one of the major elements in today's most electronic devices. As... more Touching devices have become one of the major elements in today's most electronic devices. As the increasing demands of large touching area, the state-of-the-art touching approaches become costly and infeasible. Therefore, it is essential to design a new kind of touch techniques with high touching accuracy and scalability with touching panel size. The purpose of this paper is to provide a touch system that uses the distance between the object (finger or stylus) and its shadow to detect the touch-timing and position. It can be applied to an interactive projection system without using large amount of touch-detecting elements. The proposed touch system only requires a camera and an IR source with an interactive projector to detect the occurrence of touching and its location. The proposed system achieves an average detection rate of 97.53% when the error tolerance is 10 pixels.

IEEE International Conference on Acoustics Speech and Signal Processing, 2002

AN AUTOMATED IP SYNTHESIZER FOR LIMITED-RESOURCE DWT PROCESSOR Ting-Hsun Wei, Shiuh-Rong Huang, a... more AN AUTOMATED IP SYNTHESIZER FOR LIMITED-RESOURCE DWT PROCESSOR Ting-Hsun Wei, Shiuh-Rong Huang, and Lan-Rong Dung Department of Electrical and Control Engineering National Chiao Tung University Hsinchu, Taiwan, ROC lennon@cn.nctu.edu.tw ...

Journal of Computer and Communications, 2014

Electrical impedance tomography (EIT) is a fast and cost-effective technique that provides a tomo... more Electrical impedance tomography (EIT) is a fast and cost-effective technique that provides a tomographic conductivity image of a subject from boundary current-voltage data. This paper proposes a time and memory efficient method for solving a large scale 3D EIT image reconstruction problem and the ill-posed linear inverse problem. First, we use block-based sampling for a large number of measured data from many electrodes. This method will reduce the size of Jacobian matrix and can improve accuracy of reconstruction by using more electrodes. And then, a sparse matrix reduction technique is proposed using thresholding to set very small values of the Jacobian matrix to zero. By adjusting the Jacobian matrix into a sparse format, the element with zeros would be eliminated, which results in a saving of memory requirement. Finally, we built up the relationship between compressed sensing and EIT definitely and induce the CS: two-step Iterative Shrinkage/Thresholding and block-based method into EIT image reconstruction algorithm. The results show that block-based compressed sensing enables the large scale 3D EIT problem to be efficient. For a 72-electrodes EIT system, our proposed method could save at least 61% of memory and reduce time by 72% than compressed sensing method only. The improvements will be obvious by using more electrodes. And this method is not only better at anti-noise, but also faster and better resolution.

2006 IEEE Asian Solid-State Circuits Conference, 2006

This paper presents a sigma-delta (ΣΔ) analog-to-digital converter (ADC) for the extended bandwid... more This paper presents a sigma-delta (ΣΔ) analog-to-digital converter (ADC) for the extended bandwidth asymmetric digital subscriber line application (ADSL2+). The core of the ADC is a cascaded 2-1-1 ΣΔ modulator that employs a resonator-based topology in the first stage, three tri-level quantizers, and two different pairs of reference voltages. As shown in the experimental result, for a 2.2 MHz signal