Low Resolution Thermal Array Sensors are widely used in several applications in indoor environments. In particular, one of these cheap, small and unobtrusive sensors provides a low-resolution thermal image of the envi...Low Resolution Thermal Array Sensors are widely used in several applications in indoor environments. In particular, one of these cheap, small and unobtrusive sensors provides a low-resolution thermal image of the environment and, unlike cameras;it is capable to detect human heat emission even in dark rooms. The obtained thermal data can be used to monitor older seniors while they are performing daily activities at home, to detect critical situations such as falls. Most of the studies in activity recognition using Thermal Array Sensors require human detection techniques to recognize humans passing in the sensor field of view. This paper aims to improve the accuracy of the algorithms used so far by considering the temperature environment variation. This method leverages an adaptive background estimation and a noise removal technique based on Kalman Filter. In order to properly validate the system, a novel installation of a single sensor has been implemented in a smart environment: the obtained results show an improvement in human detection accuracy with respect to the state of the art, especially in case of disturbed environments.展开更多
A novel moving object detection method was proposed in order to adapt the difficulties caused by intermittent object motion,thermal and dynamic background sequences.Two groups of complementary Gaussian mixture models ...A novel moving object detection method was proposed in order to adapt the difficulties caused by intermittent object motion,thermal and dynamic background sequences.Two groups of complementary Gaussian mixture models were used.The ghost and real static object could be classified by comparing the similarity of the edge images further.In each group,the multi resolution Gaussian mixture models were used and dual thresholds were applied in every resolution in order to get a complete object mask without much noise.The computational color model was also used to depress illustration variations and light shadows.The proposed method was verified by the public test sequences provided by the IEEE Change Detection Workshop and compared with three state-of-the-art methods.Experimental results demonstrate that the proposed method is better than others for all of the evaluation parameters in intermittent object motion sequences.Four and two in the seven evaluation parameters are better than the others in thermal and dynamic background sequences,respectively.The proposed method shows a relatively good performance,especially for the intermittent object motion sequences.展开更多
为了准确提取作物冠层温度,监测作物水分亏缺状态,以不同水分处理的生菜为研究对象,分别利用手持式热像仪和佳能相机获取生菜的热红外和可见光图像,计算生菜冠层可见光图像与热红外图像的仿射变换参数,并进行配准融合,以获取生菜冠层区...为了准确提取作物冠层温度,监测作物水分亏缺状态,以不同水分处理的生菜为研究对象,分别利用手持式热像仪和佳能相机获取生菜的热红外和可见光图像,计算生菜冠层可见光图像与热红外图像的仿射变换参数,并进行配准融合,以获取生菜冠层区域的热红外图像,而后计算不同处理下的基于冠层温度的水分胁迫指数(Crop Water Stress Index, CWSI)与日蒸散量(Evapotranspiration,ET),分析不同灌溉处理下CWSI同ET的相关关系来监测生菜水分亏缺程度。结果表明,基于仿射变换的热红外目标提取方法可以实现生菜冠层的准确提取,剔除背景后生菜冠层的平均温度值由20.25℃下降至19.25℃。不同水分处理下的生菜热红外冠层的CWSI值展示出明显的差异,且CWSI与ET呈显著负相关,当CWSI越大,ET越小,表明CWSI可以应用在生菜水分胁迫状态监测,能够很好的反应土壤水分含量变化状况。展开更多
文摘Low Resolution Thermal Array Sensors are widely used in several applications in indoor environments. In particular, one of these cheap, small and unobtrusive sensors provides a low-resolution thermal image of the environment and, unlike cameras;it is capable to detect human heat emission even in dark rooms. The obtained thermal data can be used to monitor older seniors while they are performing daily activities at home, to detect critical situations such as falls. Most of the studies in activity recognition using Thermal Array Sensors require human detection techniques to recognize humans passing in the sensor field of view. This paper aims to improve the accuracy of the algorithms used so far by considering the temperature environment variation. This method leverages an adaptive background estimation and a noise removal technique based on Kalman Filter. In order to properly validate the system, a novel installation of a single sensor has been implemented in a smart environment: the obtained results show an improvement in human detection accuracy with respect to the state of the art, especially in case of disturbed environments.
基金Project(T201221207)supported by the Fundamental Research Fund for the Central Universities,ChinaProject(2012CB725301)supported by National Basic Research and Development Program,China
文摘A novel moving object detection method was proposed in order to adapt the difficulties caused by intermittent object motion,thermal and dynamic background sequences.Two groups of complementary Gaussian mixture models were used.The ghost and real static object could be classified by comparing the similarity of the edge images further.In each group,the multi resolution Gaussian mixture models were used and dual thresholds were applied in every resolution in order to get a complete object mask without much noise.The computational color model was also used to depress illustration variations and light shadows.The proposed method was verified by the public test sequences provided by the IEEE Change Detection Workshop and compared with three state-of-the-art methods.Experimental results demonstrate that the proposed method is better than others for all of the evaluation parameters in intermittent object motion sequences.Four and two in the seven evaluation parameters are better than the others in thermal and dynamic background sequences,respectively.The proposed method shows a relatively good performance,especially for the intermittent object motion sequences.
文摘为了准确提取作物冠层温度,监测作物水分亏缺状态,以不同水分处理的生菜为研究对象,分别利用手持式热像仪和佳能相机获取生菜的热红外和可见光图像,计算生菜冠层可见光图像与热红外图像的仿射变换参数,并进行配准融合,以获取生菜冠层区域的热红外图像,而后计算不同处理下的基于冠层温度的水分胁迫指数(Crop Water Stress Index, CWSI)与日蒸散量(Evapotranspiration,ET),分析不同灌溉处理下CWSI同ET的相关关系来监测生菜水分亏缺程度。结果表明,基于仿射变换的热红外目标提取方法可以实现生菜冠层的准确提取,剔除背景后生菜冠层的平均温度值由20.25℃下降至19.25℃。不同水分处理下的生菜热红外冠层的CWSI值展示出明显的差异,且CWSI与ET呈显著负相关,当CWSI越大,ET越小,表明CWSI可以应用在生菜水分胁迫状态监测,能够很好的反应土壤水分含量变化状况。
