摘要:
What is disclosed is a system and method for recovering a patient's cardiac pulse rate from a sequence of video images recording of that patient. In one embodiment, a reference signal of a particular frequency is generated at predetermined frequency intervals and a constrained source separation is performed on the source data to obtain an estimation of the source signal intended to be recovered. The reference signal is updated and constrained source separation is again performed. These operations are repeated for all frequencies of the reference signal. The frequency at which a minimum error is achieved is determined to be the subject's recovered cardiac pulse frequency. In such a manner, the source signal is extracted and recovered reliably from captured multi-channel RGB signals or multispectral signals. The teachings hereof find their uses in a variety of medical solutions including various military, security and telemedicine applications. Various embodiments are disclosed.
摘要:
What is disclosed is a video-based system and method for estimating heart rate variability from time-series signals generated from video images captured of a subject of interest being monitored for cardiac function. In a manner more fully disclosed herein, low frequency and high frequency components are extracted from a time-series signal obtained by processing a video of the subject being monitored. A ratio of the low and high frequency of the integrated power spectrum within these components is computed. Analysis of the dynamics of this ratio over time is used to estimate heart rate variability. The teachings hereof can be used in a continuous monitoring mode with a relatively high degree of measurement accuracy and find their uses in a variety of diverse applications such as, for instance, emergency rooms, cardiac intensive care units, neonatal intensive care units, and various telemedicine applications.
摘要:
What is disclosed is a computationally efficient system and method for estimating a subject's cardiac pulse rate from multi-channel source video data. In one embodiment, A time-series signal is received. A sliding window is used to define overlapping segments of the time-series signal. Signal segments are processed by performing constrained independent component analysis (cICA) until convergence to obtain an estimated source signal. A frequency of each estimated source signal obtained by the cICA at convergence is determined to be the subject's estimated cardiac pulse rate for each signal segment. A seed reference signal used by the cICA is repeatedly updated. A sliding window is shifted to define a next time-series signal segment for processing. The method repeats for each signal segment until a termination criteria is met. In such a manner, the subject's cardiac pulse rate is estimated from a video of the subject on a continuous basis.
摘要:
What is disclosed is a system and method for determining an arterial pulse transit time of a subject of interest in a remote sensing environment. A video imaging system is used to capture a time varying source images of a proximal and distal region of a subject intended to be analyzed for arterial pulse transit time. A time series signal for each of the proximal and distal regions is extracted from the source images and a phase of each of the extracted time series signals is computed. A difference is then computed between these phases. This phase difference is a monotonic function of frequencies in the signals. From the monotonic function, an arterial pulse transit time of the subject is extracted. The subject's arterial pulse transit time is then communicated to a computer system. The computer system determines blood pressure, blood vessel blockage, blood flow velocity, or a peripheral neuropathy.