We propose a novel method on stereo matching based on the Global Edge Constraint (GEC) and Graph ... more We propose a novel method on stereo matching based on the Global Edge Constraint (GEC) and Graph Cuts. Firstly, the GEC composed of particular image edges is employed to generate the initial disparity maps. And then the reliable disparity maps consistent with the observed data are extracted to construct the data term of the energy function. Finally, we incorporate the GEC as a soft constraint into our global optimization framework, and the optimal solution could be approximated via graph cuts. Experimental results demonstrated the good performance of our proposed approach.
To develop an artificial intelligence (AI)-based algorithm which can automatically detect food it... more To develop an artificial intelligence (AI)-based algorithm which can automatically detect food items from images acquired by an egocentric wearable camera for dietary assessment. To study human diet and lifestyle, large sets of egocentric images were acquired using a wearable device, called eButton, from free-living individuals. Three thousand nine hundred images containing real-world activities, which formed eButton data set 1, were manually selected from thirty subjects. eButton data set 2 contained 29 515 images acquired from a research participant in a week-long unrestricted recording. They included both food- and non-food-related real-life activities, such as dining at both home and restaurants, cooking, shopping, gardening, housekeeping chores, taking classes, gym exercise, etc. All images in these data sets were classified as food/non-food images based on their tags generated by a convolutional neural network. A cross data-set test was conducted on eButton data set 1. The ove...
IEEE Transactions on Circuits and Systems I: Regular Papers
Systolic implementation of Karatsuba algo- rithm (KA)-based digit-serial multiplier over <inli... more Systolic implementation of Karatsuba algo- rithm (KA)-based digit-serial multiplier over <inline-formula> <tex-math notation="LaTeX">$GF(2^{m})$ </tex-math></inline-formula> on field- programmable gate array (FPGA) platforms has many attractive features, such as efficient tradeoff in area-time complexity and high-throughput rate. But on the other side, it suffers from high register-complexity, which leads to increase in area and power consumption. In this paper, we present an algorithm and architecture for efficient FPGA implementation of KA-based digit-serial systolic multiplier over <inline-formula> <tex-math notation="LaTeX">$GF(2^{m})$ </tex-math></inline-formula> based on the National Institute of Standards and Technology (NIST) recommended polynomials. A number of efficient techniques have been explored and used to realize efficient implementation of these multipliers. First, we propose a novel KA-based approach, where the computational complexity is significantly reduced compared with the existing one. Second, we propose efficient register minimization techniques, such as redundant register removal, two-stage pipelining, and register sharing to reduce the register complexity of the proposed structure. Third, we adopt an efficient FPGA-specific digit-parallel implementation strategy to optimize the area-time–power complexities of the proposed structure on FPGA platforms. The results obtained from FPGA synthesis indicate that the proposed multiplier (for field based on NIST trinomial <inline-formula> <tex-math notation="LaTeX">$GF(2^{233})$ </tex-math></inline-formula>) has significantly lower area–time–power complexities than the existing designs, e.g., the proposed structure could achieve 65.7% and 73.6% reduction on area-delay product and power-delay product over the best of existing KA-based systolic structures, respectively.
Proceedings of the The 51st Annual Design Automation Conference on Design Automation Conference - DAC '14, 2014
Recent advances in mobile devices have made profound changes in people&amp;amp;amp;amp;amp;am... more Recent advances in mobile devices have made profound changes in people&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s daily lives. In particular, the impact of easy access of information by the smartphone has been tremendous. However, the impact of mobile devices on healthcare has been limited. Diagnosis and treatment of diseases are still initiated by occurrences of symptoms, and technologies and devices that emphasize on disease prevention and early detection outside hospitals are under-developed. Besides healthcare, mobile devices have not yet been designed to fully benefit people with special needs, such as the elderly and those suffering from certain disabilities, such blindness. In this paper, an overview of our research on a new wearable computer called eButton is presented. The concepts of its design and electronic implementation are described. Several applications of the eButton are described, including evaluating diet and physical activity, studying sedentary behavior, assisting the blind and visually impaired people, and monitoring older adults suffering from dementia.
Retinex is one of the well-known schemes for adaptive image enhancement under poor weather condit... more Retinex is one of the well-known schemes for adaptive image enhancement under poor weather conditions. Improving the visibility of input images on a target detection system is necessary to insure detection work properly. Compared to other realization methods based on DSPs and FPGAs, this paper proposes a totally parallel structure based on FPGA to implement multi-scale Retinex for an outdoor application. Gaussian kernel is optimized with address encoding and distributed arithmetic, and parallel multi-scale convolutions are realized. No frame buffer is needed for the proposed implementation itself, so the system delay is greatly saved. Experiments show the good performance of the proposed multi-scale Retinex implementation by both subjective and objective assessments. Visibility of images suffering from fog degradation and uneven light is improved. And future work is presented in the conclusion.
Recently, wearable computers have become new members in the family of mobile electronic devices, ... more Recently, wearable computers have become new members in the family of mobile electronic devices, adding new functions to those provided by smartphones and tablets. As &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;always-on&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; miniature computers in the personal space, they will play increasing roles in the field of healthcare. In this work, we present our development of eButton, a wearable computer designed as a personalized, attractive, and convenient chest pin in a circular shape. It contains a powerful microprocessor, numerous electronic sensors, and wireless communication links. We describe its design concepts, electronic hardware, data processing algorithms, and its applications to the evaluation of diet, physical activity and lifestyle in the study of obesity and other chronic diseases.
This paper introduces the design and realization of a wearable device for dietary and physical ac... more This paper introduces the design and realization of a wearable device for dietary and physical activity monitoring. This design is based on technological advances in microelectronics and our previous prototypes which have verified the system concept. From our results, it is shown that the device meets all functional requirements as well as size and power consumption constraints essential to participants' use. With further technological development, we believe that the size of the system can be reduced and accurate and objective dietary assessments will become possible.
ABSTRACT Most image dehazing methods are based on the dichromatic atmospheric scattering model. H... more ABSTRACT Most image dehazing methods are based on the dichromatic atmospheric scattering model. However, this model cannot explain blurring effects. In this paper, we present a detail loss compensating model, based on the analysis of multiple scattering model. By assuming that the foggy image has less detail than the image captured on a clear day, we use the Laplacian template and present a smoothing point spread function to estimate the detail loss of a foggy image. The fog noise is subsequently obtained based on the estimated detail loss, and the inherent radiance of the scene can therefore be restored. Experimental results show that our method have good dehazing effect and enhance the image sharpness to a certain extent.
We propose a novel method on stereo matching based on the Global Edge Constraint (GEC) and Graph ... more We propose a novel method on stereo matching based on the Global Edge Constraint (GEC) and Graph Cuts. Firstly, the GEC composed of particular image edges is employed to generate the initial disparity maps. And then the reliable disparity maps consistent with the observed data are extracted to construct the data term of the energy function. Finally, we incorporate the GEC as a soft constraint into our global optimization framework, and the optimal solution could be approximated via graph cuts. Experimental results demonstrated the good performance of our proposed approach.
To develop an artificial intelligence (AI)-based algorithm which can automatically detect food it... more To develop an artificial intelligence (AI)-based algorithm which can automatically detect food items from images acquired by an egocentric wearable camera for dietary assessment. To study human diet and lifestyle, large sets of egocentric images were acquired using a wearable device, called eButton, from free-living individuals. Three thousand nine hundred images containing real-world activities, which formed eButton data set 1, were manually selected from thirty subjects. eButton data set 2 contained 29 515 images acquired from a research participant in a week-long unrestricted recording. They included both food- and non-food-related real-life activities, such as dining at both home and restaurants, cooking, shopping, gardening, housekeeping chores, taking classes, gym exercise, etc. All images in these data sets were classified as food/non-food images based on their tags generated by a convolutional neural network. A cross data-set test was conducted on eButton data set 1. The ove...
IEEE Transactions on Circuits and Systems I: Regular Papers
Systolic implementation of Karatsuba algo- rithm (KA)-based digit-serial multiplier over <inli... more Systolic implementation of Karatsuba algo- rithm (KA)-based digit-serial multiplier over <inline-formula> <tex-math notation="LaTeX">$GF(2^{m})$ </tex-math></inline-formula> on field- programmable gate array (FPGA) platforms has many attractive features, such as efficient tradeoff in area-time complexity and high-throughput rate. But on the other side, it suffers from high register-complexity, which leads to increase in area and power consumption. In this paper, we present an algorithm and architecture for efficient FPGA implementation of KA-based digit-serial systolic multiplier over <inline-formula> <tex-math notation="LaTeX">$GF(2^{m})$ </tex-math></inline-formula> based on the National Institute of Standards and Technology (NIST) recommended polynomials. A number of efficient techniques have been explored and used to realize efficient implementation of these multipliers. First, we propose a novel KA-based approach, where the computational complexity is significantly reduced compared with the existing one. Second, we propose efficient register minimization techniques, such as redundant register removal, two-stage pipelining, and register sharing to reduce the register complexity of the proposed structure. Third, we adopt an efficient FPGA-specific digit-parallel implementation strategy to optimize the area-time–power complexities of the proposed structure on FPGA platforms. The results obtained from FPGA synthesis indicate that the proposed multiplier (for field based on NIST trinomial <inline-formula> <tex-math notation="LaTeX">$GF(2^{233})$ </tex-math></inline-formula>) has significantly lower area–time–power complexities than the existing designs, e.g., the proposed structure could achieve 65.7% and 73.6% reduction on area-delay product and power-delay product over the best of existing KA-based systolic structures, respectively.
Proceedings of the The 51st Annual Design Automation Conference on Design Automation Conference - DAC '14, 2014
Recent advances in mobile devices have made profound changes in people&amp;amp;amp;amp;amp;am... more Recent advances in mobile devices have made profound changes in people&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s daily lives. In particular, the impact of easy access of information by the smartphone has been tremendous. However, the impact of mobile devices on healthcare has been limited. Diagnosis and treatment of diseases are still initiated by occurrences of symptoms, and technologies and devices that emphasize on disease prevention and early detection outside hospitals are under-developed. Besides healthcare, mobile devices have not yet been designed to fully benefit people with special needs, such as the elderly and those suffering from certain disabilities, such blindness. In this paper, an overview of our research on a new wearable computer called eButton is presented. The concepts of its design and electronic implementation are described. Several applications of the eButton are described, including evaluating diet and physical activity, studying sedentary behavior, assisting the blind and visually impaired people, and monitoring older adults suffering from dementia.
Retinex is one of the well-known schemes for adaptive image enhancement under poor weather condit... more Retinex is one of the well-known schemes for adaptive image enhancement under poor weather conditions. Improving the visibility of input images on a target detection system is necessary to insure detection work properly. Compared to other realization methods based on DSPs and FPGAs, this paper proposes a totally parallel structure based on FPGA to implement multi-scale Retinex for an outdoor application. Gaussian kernel is optimized with address encoding and distributed arithmetic, and parallel multi-scale convolutions are realized. No frame buffer is needed for the proposed implementation itself, so the system delay is greatly saved. Experiments show the good performance of the proposed multi-scale Retinex implementation by both subjective and objective assessments. Visibility of images suffering from fog degradation and uneven light is improved. And future work is presented in the conclusion.
Recently, wearable computers have become new members in the family of mobile electronic devices, ... more Recently, wearable computers have become new members in the family of mobile electronic devices, adding new functions to those provided by smartphones and tablets. As &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;always-on&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; miniature computers in the personal space, they will play increasing roles in the field of healthcare. In this work, we present our development of eButton, a wearable computer designed as a personalized, attractive, and convenient chest pin in a circular shape. It contains a powerful microprocessor, numerous electronic sensors, and wireless communication links. We describe its design concepts, electronic hardware, data processing algorithms, and its applications to the evaluation of diet, physical activity and lifestyle in the study of obesity and other chronic diseases.
This paper introduces the design and realization of a wearable device for dietary and physical ac... more This paper introduces the design and realization of a wearable device for dietary and physical activity monitoring. This design is based on technological advances in microelectronics and our previous prototypes which have verified the system concept. From our results, it is shown that the device meets all functional requirements as well as size and power consumption constraints essential to participants' use. With further technological development, we believe that the size of the system can be reduced and accurate and objective dietary assessments will become possible.
ABSTRACT Most image dehazing methods are based on the dichromatic atmospheric scattering model. H... more ABSTRACT Most image dehazing methods are based on the dichromatic atmospheric scattering model. However, this model cannot explain blurring effects. In this paper, we present a detail loss compensating model, based on the analysis of multiple scattering model. By assuming that the foggy image has less detail than the image captured on a clear day, we use the Laplacian template and present a smoothing point spread function to estimate the detail loss of a foggy image. The fog noise is subsequently obtained based on the estimated detail loss, and the inherent radiance of the scene can therefore be restored. Experimental results show that our method have good dehazing effect and enhance the image sharpness to a certain extent.
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Papers by Yuecheng Li