容积脉搏成像特征提取方法研究及在生理信号检测的应用

发布时间：2018-01-01 06:42

  本文关键词：容积脉搏成像特征提取方法研究及在生理信号检测的应用　出处：《哈尔滨工业大学》2016年博士论文　论文类型：学位论文

  更多相关文章： 容积脉搏成像 特征提取 心率 脉搏波传导时间 血氧饱和度

【摘要】：脉搏波蕴藏了丰富生命信息。通过对脉搏波的形态、强度、速度和节律的分析,可以获得生理和病理特征。在环境光条件下使用摄像头能提取容积脉搏波,它是借助容积脉搏成像(Photoplethysmographic imaging,PPGi)检测血液容积变化的方法,通过计算PPGi图像像素均值使二维信号转化为一维信号可以获得容积脉搏波。日益普及带有摄像头智能手机和移动式个人终端设备提供了一个低成本和泛在式的健康感知平台,人们可以在非医院、非约束的环境下使用移动终端设备长时间实时动态地评估个人的健康状况,达到对疾病的早期预警、早期预防、早期发现、早期诊断和早期治疗的目的。可以预料,受智能终端设备巨大市场潜力的驱动,PPGi检测生理信息的应用前景广大,它对移动医疗的推广和普及具有重要的现实意义,可以称之为泛在式生命体征检测的一个新方法。然而由于PPGi受到光照环境、摄像头对光的敏感度、低采样率和运动伪迹等因素的限制,目前PPGi的应用仅仅局限于心率和呼吸率的检测。基于以上问题,本文首先针对在不同光照环境下PPGi特征进行深入分析,然后开发基于PPGi的容积脉搏波特征点提取方法,最后提出基于PPGi的心率、脉搏波传导时间(Pulse Transit Time,PTT)和血氧饱和度(Blood Oxygen Saturation,Sp O2)检测方法。本文开展以下几项研究:(1)研究在不同光照环境下PPGi的特征。光源波长和摄像头对PPGi有着重要的影响,实验分别使用不同波长光和光强作为照明光评估基于PPGi特征。研究结果表明:不同波长光下基于PPGi计算的心率与金标准(金标准指当前临床医学界公认的诊断疾病的最可靠、最准确、最好的诊断方法)心率具有良好的一致性,仅仅在470nm、490nm、505nm、585nm、600nm、610nm、625nm、660nm波长光和白光作为照明光下,基于PPGi的容积脉搏波与金标准PPG信号波形具有良好的相关性;在600nm、610nm、625nm、660nm波长光和白光作为照明光下,随着光强增加,基于PPGi的容积脉搏波直流强度增加,但是交流强度有一个增加到下降的趋势。这些结果表明照明光的波长不会影响到PPGi计算心率,而照明光的波长和光的强度会影响PPGi的特征,为深入挖掘基于PPGi的生理信息检测提供理论基础。(2)研究基于PPGi的容积脉搏波特征点提取方法。针对基于PPGi的容积脉搏波具有基线漂移较大、采样率低及分光现象等问题,提出基于PPGi的容积脉搏波特征点提取方法:提出使用重排平滑伪Wigner-Ville分布方法计算基于PPGi的容积脉搏波交流和直流强度;提出“自适应二次曲线门限”方法检测基于PPGi的容积脉搏波峰和波谷;提出“二次曲线拟合”方法提高基于PPGi的容积脉搏波峰和波谷检测准确度;提出“自适应区域变化”方法消除PPGi分光现象。通过计算基于PPGi的多个体表部位(手指端和太阳穴)心率和PTT,验证此方法可以提高基于PPGi的容积脉搏波特征点检测精度。(3)研究基于PPGi的心率检测方法。首先评估基于PPGi的计算心率作为人脸区域特征的可行性;然后基于此原理,从脸部提取PPGi作为独特的特征,区分人脸颜色相似背景环境中的人脸轮廓。使用相邻4像素方法加强人脸区域可靠性,使用罗伯特算子创建脸部形状区域。实验结果表明基于PPGi的人脸检测方法可以提高复杂和具有相似背景场景下人脸检测的鲁棒性。(4)研究基于PPGi的Sp O2检测方法。首先在已分析不同波长光下基于PPGi的容积脉搏波特征的基础上,选择660nm和800nm波长光作为照明光,同时提取人体右手食指端与右手大拇指端的PPGi;然后在已建立基于PPGi的容积脉搏波特征点提取方法的基础上,获得基于PPGi的容积脉搏波特征点的交流和直流强度,并计算SpO2。实验结果表明,与金标准Sp O2比较,95%的置信区间分布范围达到?%2,体现良好的一致性。
[Abstract]:The pulse wave contains the abundant life information. Based on the pulse wave shape, intensity, speed and rhythm analysis, can get the physiological and pathological characteristics. Using the camera under ambient light conditions can extract pulse wave, it is through the use of volume pulse imaging (Photoplethysmographic imaging PPGi) method for detection of blood volume changes, through calculation PPGi image pixel average the two-dimensional signal into a one-dimensional signal can obtain volume pulse wave. The growing popularity of smart mobile phone with a camera and personal mobile terminal equipment to provide a low cost and ubiquitous health perception platform, people can not in the hospital, to evaluate the personal health status using the real-time dynamic mobile terminal equipment long time the non restraint environment, to achieve early warning of the disease, early prevention, early detection, early diagnosis and treatment purposes. It can be expected that by Driving intelligent terminal equipment huge market potential and application prospect of PPGi detection of physiological information is vast, it has important practical significance for the promotion and popularization of mobile medical, can be called the pan in a new method of vital signs detection. However due to the PPGi by the light environment, the sensitivity of the low light camera. The sampling rate and motion artifacts and other factors, the current PPGi application only to detect the heart rate and respiratory rate. Based on the above problems, this paper firstly according to the PPGi characteristics in different light environment in-depth analysis, and then develops a method for extracting feature points of pulse wave based on PPGi, and finally puts forward the PPGi based on the heart rate. Pulse transit time (Pulse Transit, Time, PTT) and oxygen saturation (Blood Oxygen Saturation, Sp O2) detection method. This paper carried out the following research: (1) study in different light environments PPGi The wavelength of light source and camera features. Has an important influence on the PPGi, experiments were made using different wavelengths of light intensity and light for evaluation based on the characteristics of PPGi. The results show that the PPGi calculation of the heart rate and the gold standard based on different wavelengths of light (the gold standard to diagnose diseases of current clinical medical profession recognized the most reliable, most accurate the best diagnostic method, heart rate) has good consistency, only in 470nm, 490nm, 505nm, 585nm, 600nm, 610nm, 625nm, 660nm wavelength and white light for PPGi, the volume pulse wave with the gold standard PPG signal waveform has a good correlation based in 600nm, 610nm, 625nm; 660nm. Wavelength and white light for, with the increase of light intensity, the increase of volume pulse wave DC intensity based on PPGi, but the exchange strength there is an increase to a downward trend. These results show that the wavelength of the illumination light does not affect PPGi to calculating the heart rate, and the light intensity of the light wavelength and light will affect the characteristics of PPGi, and provide a theoretical basis for further mining the physiological information detection based on PPGi. (2) research on pulse wave feature extraction method based on PPGi. Based on the PPGi volume pulse wave with base line drift is large, low sampling rate and the problem of optical phenomena, extraction method of volume pulse wave feature points based on PPGi put forward the pseudo Wigner-Ville distribution calculation for PPGi volume pulse wave AC and DC strength based on the use of rearrangement smoothing; put forward "two curve adaptive detection threshold method PPGi volume pulse peak and trough based on the proposed" two curve fitting; "the way to improve the PPGi volume pulse peak and trough detection based on accuracy; put forward the" adaptive regional change "method to eliminate PPGi light phenomenon. By calculating the individual based on PPGi Table parts (finger and temple) and heart rate PTT, verify that this method can improve the volume pulse wave feature point detection accuracy based on PPGi. (3) research on heart rate detection method based on PPGi. Firstly, based on PPGi evaluation and calculation of heart rate as a regional feasibility of facial features; then based on the principle of extracting PPGi from the face as a unique the characteristics of face contour distinguish face similar color background. Using 4 adjacent pixels method to strengthen the face region reliability, using the Robert operator to create the shape of the face region. The experimental results show that the face detection method based on PPGi can improve the complexity and robustness of face detection with similar background scenes. (4) Sp O2 detection method based on PPGi. Firstly, based on the characteristics of pulse wave on PPGi has been analyzed under different wavelengths of light, 660nm and 800nm wavelength as the light, at the same time Extraction of human finger end with the thumb of the right hand side of the PPGi; and has been established in the volume pulse wave extraction method based on feature points based on PPGi, obtain the volume pulse wave characteristics of PPGi AC and DC based on strength calculation and experimental results show that the SpO2. Sp O2 and the gold standard comparison, 95% confidence interval the distribution range of up to?%2, reflect the good consistency.

【学位授予单位】：哈尔滨工业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TN911.23;R318

【相似文献】

相关期刊论文 前1条

1 崔波;高博;龚敏;;基于红外反射光容积脉搏波的血管阻力研究[J];光散射学报;2011年04期

相关会议论文 前2条

1 赵兰平;杨学智;牛欣;;指端容积脉搏波的动态血氧饱和度测定及应用[A];中国生理学会第23届全国会员代表大会暨生理学学术大会论文摘要文集[C];2010年

2 宋娟;张松;罗志昌;杨益民;;应用指端容积脉搏波检测与预测妊高征及其机理研究[A];中国生物医学工程学会第六次会员代表大会暨学术会议论文摘要汇编[C];2004年

相关博士学位论文 前2条

1 刘赫;容积脉搏成像特征提取方法研究及在生理信号检测的应用[D];哈尔滨工业大学;2016年

2 丁海泉;无创血糖检测中的近红外血流容积光谱基本问题研究[D];中国科学院研究生院（长春光学精密机械与物理研究所）;2010年

相关硕士学位论文 前3条

1 张雪;基于容积脉搏波的微循环特性研究[D];燕山大学;2012年

2 丁有得;基于容积脉搏波血流多参数测量的研究[D];南方医科大学;2010年

3 王锦;电刺激小脑顶核对容积脉搏波参数影响的研究[D];重庆大学;2010年

，

本文编号：1363395