公开(公告)号：US20140160355A1

公开(公告)日：2014-06-12

申请号：US13708125

申请日：2012-12-07

Applicant: XEROX CORPORATION

Inventor： Lalit Keshav MESTHA ,  Survi KYAL ,  Sohail A. DIANAT

IPC: H04N5/14

CPC classification number: G06T3/4007 ,  G06T3/4053 ,  H04N7/01 ,  H04N7/0135

Abstract: What is disclosed is a novel video processing system and method wherein a plurality of image frames of a video captured using a video camera with a spatial resolution of (M×N) in the (x, y) direction, respectively, and a temporal resolution (T) in frames per unit of time. A first and second magnification factor f1, f2 are selected for spatial enhancement in the (x, y) direction. A third magnification factor f3 is selected for a desired temporal enhancement in (T). The video data is processed using a dictionary comprising high and low resolution patch cubes which are used to induce spatial and temporal components in the video where no data exists. A high resolution course video X0 is generated which has an enhanced spatial resolution of (f1* M)×(f2*N) and an enhanced temporal resolution of (f3*T) frames. The course high resolution video is then smoothed, when found required, to generate a smoothed high resolution video.

Abstract translation: 所公开的是一种新颖的视频处理系统和方法，其中使用在（x，y）方向上具有（M×N）的空间分辨率的摄像机捕获的视频的多个图像帧分别为（x，y） （T）以每单位时间的帧为单位。 选择第一和第二放大因子f1，f2用于（x，y）方向上的空间增强。 在（T）中为期望的时间增强选择第三放大因子f3。 使用包括高分辨率和低分辨率片段立方体的字典来处理视频数据，这些立方体用于在没有数据存在的视频中诱导空间和时间分量。 产生具有（f1 * M）×（f2 * N）的增强的空间分辨率和（f3 * T）帧的增强的时间分辨率的高分辨率过程视频X0。 当高分辨率视频被发现时需要平滑化，以产生平滑的高分辨率视频。

公开(公告)号：US20160287105A1

公开(公告)日：2016-10-06

申请号：US14674791

申请日：2015-03-31

Applicant: Xerox Corporation

Inventor： Luisa Fernanda POLANIA-CABRERA ,  Lalit Keshav MESTHA

IPC: A61B5/024 ,  A61B5/00

CPC classification number: A61B5/02416 ,  A61B5/0002 ,  A61B5/02028 ,  A61B5/7264 ,  A61B5/7282 ,  A61B5/746

Abstract: What is disclosed is a system and method for classifying a time-series signal as being ventricular premature contraction, ventricular tachycardia, or normal sinus rhythm in a patient being monitored for cardiac function assessment. One embodiment hereof involves the following. A time-series signal is received which contains frequency components that relate to the function of the subject's heart. Signal segments of interest are identified in the time-series signal. Time-domain features, frequency-domain features, and non-linear cardiac dynamics are extracted from each of the identified signal segments of interest. The extracted features and dynamics become components of at least one feature vector associated with each respective signal segment of interest. Signal segments are then classified as one of: ventricular premature contraction, ventricular tachycardia, and normal sinus rhythm, based on each signal segment's respective feature vector(s).

Abstract translation: 所公开的是将时间序列信号分类为被监测用于心脏功能评估的患者中的室性早搏，室性心动过速或正常窦性心律的系统和方法。 其一个实施方案涉及以下。 接收时间序列信号，其包含与被摄体心脏的功能相关的频率分量。 感兴趣的信号段在时间序列信号中被识别。 从感兴趣的所识别的每个信号片段中提取时域特征，频域特征和非线性心脏动力学。 提取的特征和动力学变成与感兴趣的每个相应信号段相关联的至少一个特征向量的分量。 然后根据每个信号段的各自的特征向量将信号段分类为心室过早收缩，室性心动过速和正常窦性心律之一。

公开(公告)号：US20160106340A1

公开(公告)日：2016-04-21

申请号：US14519641

申请日：2014-10-21

Applicant: Xerox Corporation

Inventor： Lalit Keshav MESTHA ,  Beilei XU ,  Survi KYAL

IPC: A61B5/08 ,  A61B5/00

CPC classification number: A61B5/0816 ,  A61B5/1128 ,  A61B5/7282 ,  A61B5/746 ,  A61B5/7485 ,  A61B2576/00

Abstract: What is disclosed is a system and method for determining respiration rate from a video of a subject. In one embodiment, a video is received comprising plurality of time-sequential image frames of a region of a subject's body. Features of pixels are extracted from that region from each image frame and vectors formed from these features. Each image frame has an associated feature vector. A N×M video matrix of the vectors of length N is constructed such that a total number of columns M in the video matrix correspond to a time duration over which the subject's respiration rate is to be determined. The video matrix is processed to obtain a matrix of eigenvectors where principal axes of variations due to motion associated with respiration are contained in a first few eigenvectors. One eigenvector is selected from the first few eigenvectors. A respiration rate is obtained from the selected eigenvector.

Abstract translation: 公开的是用于从受试者的视频确定呼吸率的系统和方法。 在一个实施例中，接收包括被摄体的区域的多个时序图像帧的视频。 从每个图像帧的区域提取像素的特征，并从这些特征形成的矢量。 每个图像帧具有相关联的特征向量。 长度为N的矢量的N×M视频矩阵被构造成使得视频矩阵中的列M的总数对应于要确定被摄体的呼吸速率的持续时间。 处理视频矩阵以获得特征向量矩阵，其中由于与呼吸相关联的运动引起的变化的主轴包含在前几个特征向量中。 从前几个特征向量中选择一个特征向量。 从所选择的特征向量获得呼吸速率。

公开(公告)号：US20160106328A1

公开(公告)日：2016-04-21

申请号：US14515618

申请日：2014-10-16

Applicant: Xerox Corporation

Inventor： Lalit Keshav MESTHA ,  Survi KYAL

IPC: A61B5/021 ,  A61B5/0295 ,  A61B5/02 ,  A61B5/026 ,  A61B5/00

CPC classification number: A61B5/02125 ,  A61B5/02416 ,  A61B5/0295 ,  A61B5/1128 ,  A61B5/7253 ,  A61B5/7282

Abstract: What is disclosed is a system and method for determining arterial pulse transit time (PTT) for a subject. In one embodiment, time-series signals are received for each of a proximal and distal arterial site of a subject's body which represent blood volume changes in the microvascular tissue at each site. A proximal and distal analytic signal is obtained which has a first component being a waveform of the respective time-series signal and a second component being a transform of the respective waveform. A phase function is determined for the first and second components of each analytic signal. The phase function obtained for the proximal waveform is then subtracted from the phase function obtained for the distal waveform to get a phase difference. The phase difference is analyzed with the subject's heart rate to determine an arterial pulse wave transit time between the two proximal and distal sites.

Abstract translation: 公开的是用于确定受试者的动脉脉搏传播时间（PTT）的系统和方法。 在一个实施例中，针对受试者身体的近端和远端动脉部位的每一个接收时间序列信号，其表示每个部位的微血管组织中的血液体积变化。 获得近端和远端分析信号，其具有第一分量是相应时间序列信号的波形，第二分量是相应波形的变换。 确定每个分析信号的第一和第二分量的相位函数。 然后从为远端波形获得的相位函数中减去近端波形获得的相位函数以获得相位差。 用受试者的心率分析相位差，以确定两个近端和远端部位之间的动脉脉搏波传播时间。

公开(公告)号：US20150250391A1

公开(公告)日：2015-09-10

申请号：US14200759

申请日：2014-03-07

Applicant: XEROX CORPORATION

Inventor： Survi KYAL ,  Lalit Keshav MESTHA

IPC: A61B5/024 ,  G06T7/00 ,  A61B5/00

CPC classification number: G06T7/0014 ,  A61B5/0077 ,  A61B5/02416 ,  A61B5/746 ,  A61B2576/00 ,  G06T7/0012 ,  G06T7/20 ,  G06T2207/10016 ,  G06T2207/10024 ,  G06T2207/30004 ,  G06T2207/30088

Abstract: What is disclosed is a system and method for estimating cardiac pulse rate from a video of a subject being monitored for cardiac function. In one embodiment, batches of overlapping image frames are continuously received and processed by isolating regions of exposed skin. Pixels of the isolated regions are processed to obtain a time-series signal per region and a physiological signal is extracted from each region's time-series signals. The physiological signal is processed to obtain a cardiac pulse rate for each region. The cardiac pulse rate for each region is compared to a last good cardiac pulse rate from a previous batch to obtain a difference. If the difference exceeds a threshold, the cardiac pulse rate is discarded. Otherwise, it is retained. Once all the regions have been processed, the retained cardiac pulse rate with a minimum difference becomes the good cardiac pulse rate for comparison on a next iteration.

Abstract translation: 所公开的是用于从被监测用于心脏功能的受试者的视频估计心脏脉搏率的系统和方法。 在一个实施例中，通过隔离暴露皮肤的区域连续地接收并处理批次的重叠图像帧。 处理孤立区域的像素以获得每个区域的时间序列信号，并且从每个区域的时间序列信号中提取生理信号。 处理生理信号以获得每个区域的心脏脉搏率。 将每个区域的心脏脉搏率与来自前一批次的最后良好的心脏脉搏率进行比较以获得差异。 如果差异超过阈值，则丢弃心脏脉搏率。 否则保留。 一旦所有区域被处理，具有最小差异的保留的心脏脉搏率就成为良好的心脏脉搏率，用于在下一次迭代中进行比较。

公开(公告)号：US20150124067A1

公开(公告)日：2015-05-07

申请号：US14071355

申请日：2013-11-04

Applicant: Xerox Corporation

Inventor： Raja BALA ,  Beilei XU ,  Lalit Keshav MESTHA ,  Graham S. PENNINGTON ,  Stuart A. SCHWEID

IPC: H04N5/235 ,  H04N7/18 ,  G06T7/00 ,  G06K9/00

CPC classification number: H04N5/2354 ,  A61B5/0077 ,  A61B5/02 ,  A61B5/0205 ,  A61B5/02427 ,  A61B5/02433 ,  A61B5/0803 ,  A61B5/14552 ,  A61B5/6898 ,  G06K9/2027 ,  H04N5/2256

Abstract: What is disclosed is a handheld device having at least one illuminator for projecting source light and a video camera for capturing images of a region of interest of a subject being monitored for a desired physiological function. The handheld device is positioned such that light reflected off the subject's region of interest is received by a sensor. A determination is then made as to how a physiological signal extracted from video images captured by the video camera can be improved by an adjustment to the illuminator with respect to intensity, spectrally, spatially, and/or temporally, to improve accuracy of a measurement of a desired physiological function. The illuminator is adjusted and video images of a region of interest are captured by the video camera and processed to extract a physiological signal corresponding to that physiological function. That signal is used to monitor the desired physiological function. Various embodiments are disclosed.

Abstract translation: 所公开的是具有用于投射源光的至少一个照明器和用于捕获被监测的对象的感兴趣区域的图像用于所需生理功能的摄像机的手持设备。 手持设备被定位成使得从感兴趣区域反射的光被传感器接收。 然后，确定如何通过相对于强度，光谱，空间和/或时间上对照明器的调整来改善由摄像机拍摄的视频图像提取的生理信号，以提高测量的精度 所需的生理功能。 照明器被调整，并且摄像机捕获感兴趣区域的视频图像，并进行处理以提取对应于该生理功能的生理信号。 该信号用于监测所需的生理功能。 公开了各种实施例。

公开(公告)号：US20150003750A1

公开(公告)日：2015-01-01

申请号：US13932791

申请日：2013-07-01

Applicant: Xerox Corporation

Inventor： Edgar A. BERNAL ,  Beilei XU ,  Lalit Keshav MESTHA

IPC: G06T11/00

CPC classification number: G06T11/006 ,  G06T1/0007 ,  G06T7/11 ,  G06T2207/10004 ,  G06T2207/20052 ,  H04N5/225

Abstract: A method for reconstructing an image of a scene captured using a compressed sensing device. A mask is received which identifies at least one region of interest in an image of a scene. Measurements are then obtained of the scene using a compressed sensing device comprising, at least in part, a spatial light modulator configuring a plurality of spatial patterns according to a set of basis functions each having a different spatial resolution. A spatial resolution is adaptively modified according to the mask. Each pattern focuses incoming light of the scene onto a detector which samples sequential measurements of light. These measurements comprise a sequence of projection coefficients corresponding to the scene. Thereafter, an appearance of the scene is reconstructed utilizing a compressed sensing framework which reconstructs the image from the sequence of projection coefficients.

公开(公告)号：US20140368639A1

公开(公告)日：2014-12-18

申请号：US13920241

申请日：2013-06-18

Applicant: Xerox Corporation

Inventor： Wencheng WU ,  Edgar A. BERNAL ,  Lalit Keshav MESTHA ,  Paul R. AUSTIN

IPC: G01B11/02

CPC classification number: G01B11/00 ,  G01B11/2513 ,  H04M2250/52

Abstract: What is disclosed is a wireless cellular device capable of determining a volume of an object in an image captured by a camera of that apparatus. In one embodiment, the present wireless cellular device comprises an illuminator for projecting a pattern of structured light with known spatial characteristics, and a camera for capturing images of an object for which a volume is to be estimated. The camera is sensitive to a wavelength range of the projected pattern of structured light. A spatial distortion is introduced by a reflection of the projected pattern off a surface of the object. And processor executing machine readable program instructions for performing the method of: receiving an image of the object from the camera; processing the image to generate a depth map; and estimating a volume of the object from the depth map. A method for using the present wireless cellular device is also provided.

Abstract translation: 所公开的是能够确定由该设备的照相机拍摄的图像中的物体的体积的无线蜂窝设备。 在一个实施例中，本无线蜂窝设备包括用于投射具有已知空间特征的结构化光的图案的照明器，以及用于捕获要估计音量的对象的图像的照相机。 相机对结构光的投影图案的波长范围敏感。 通过将投影图案从物体的表面反射出来引入空间失真。 以及处理器执行机器可读程序指令，用于执行以下方法：从所述摄像机接收所述对象的图像; 处理图像以生成深度图; 并从深度图估计对象的体积。 还提供了一种使用本无线蜂窝设备的方法。

公开(公告)号：US20140221845A1

公开(公告)日：2014-08-07

申请号：US14245405

申请日：2014-04-04

Applicant: Xerox Corporation

Inventor： Lalit Keshav MESTHA ,  Beilei XU ,  Paul R. AUSTIN

IPC: A61B5/024 ,  A61B5/00

CPC classification number: A61B5/742 ,  A61B5/0044 ,  A61B5/02416 ,  A61B5/0452 ,  A61B5/7282

Abstract: What is disclosed is a system and method for processing a time-series signal generated by video images captured of a subject of interest in a non-contact, remote sensing environment such that the existence of a cardiac arrhythmia can be determined for that subject. In one embodiment, a time-series signal generated is received. The time-series signal was generated from video images captured of a region of exposed skin where photoplethysmographic (PPG) signals of a subject of interest can be registered. Signal separation is performed on the time-series signal to extract a photoplethysmographic signal for the subject. Peak-to-peak pulse points are detected in the PPG signal using an adaptive threshold technique with successive thresholds being based on variations detected in previous magnitudes of the pulse peaks. The pulse points are then analyzed to obtain peak-to-peak pulse dynamics. The existence of cardiac arrhythmias is determined for the subject based on the pulse dynamics.

Abstract translation: 所公开的是用于处理由非接触式遥感环境中感兴趣的对象捕获的视频图像产生的时间序列信号的系统和方法，使得可以确定该对象的心律失常的存在。 在一个实施例中，接收所产生的时间序列信号。 时间序列信号是从拍摄感兴趣的受试者的光学体积描记（PPG）信号可以被登记的暴露皮肤区域的视频图像产生的。 对时间序列信号执行信号分离，以提取对象的光电体积描记信号。 使用自适应阈值技术在PPG信号中检测峰峰值脉冲点，其中连续阈值基于在脉冲峰值的先前幅度中检测到的变化。 然后分析脉冲点以获得峰 - 峰脉冲动态。 基于脉搏动力学确定对象的心律失常的存在。

公开(公告)号：US20140213909A1

公开(公告)日：2014-07-31

申请号：US13755155

申请日：2013-01-31

Applicant: XEROX CORPORATION

Inventor： Lalit Keshav MESTHA ,  Palghat Srinivas RAMESH ,  Alvaro Enrique GIL

IPC: A61B5/00 ,  A61B5/1455 ,  A61B5/0205 ,  A61B5/107

CPC classification number: A61B5/0077 ,  A61B5/0075 ,  A61B5/1075 ,  A61B5/14551 ,  A61B5/443 ,  A61B5/444 ,  A61B5/7246 ,  A61B5/742 ,  A61B5/7475

Abstract: What is disclosed is a system and method for estimating a biological parameter vector for a biophysics model using reflectance measurements obtained from a reflectance-based spectral measurement system. The present method uses a semi-empirical biophysics model to describe skin properties and estimate reflectance spectra and reduces the dimensionality of the estimated and measured reflectance spectra using basis vectors for computational efficiency. A mixture of algorithms are employed to generate an initial set of parameters which, in turn, are further refined using an iterative control based technique in which the error between the parameters derived from the measured spectra are compared to the parameters calculated from the estimated spectra. These errors are then processed to generate a small delta to the initial set of parameters. The process is repeated until an error between the estimated virtual biological parameters and the measured virtual biological parameters falls to zero or is otherwise below a pre-defined threshold level.

Abstract translation: 公开的是使用从基于反射率的光谱测量系统获得的反射测量来估计生物物理学模型的生物参数矢量的系统和方法。 本方法使用半经验生物物理学模型来描述皮肤特性并估计反射光谱，并且使用用于计算效率的基矢量降低估计和测量的反射光谱的维数。 使用算法的混合来生成初始参数集合，其又使用基于迭代控制的技术进一步改进，其中将从测量的光谱导出的参数之间的误差与从估计的光谱计算的参数进行比较。 然后处理这些错误以产生初始参数集的小增量。 重复该过程，直到估计的虚拟生物参数和测量的虚拟生物学参数之间的误差落在零或否则低于预定阈值水平。