摘要:
What is disclosed is a system and method for selecting the optimal wavelength ban combination for a multi-band infrared camera system which is optimized for skin detection. An objective function is constructed specifically for this application from classified performance and the algorithm generates wavelengths by maximizing the objective function. A specific wavelength band combination is selected which maximizes the objective function. Also disclosed is a 3-band and 4-band camera system with filters each having a transmittance of one of a combination of wavelength bands optimized to detect skin in the infrared band. The camera systems disclosed herein find their intended uses in a wide array of vehicle occupancy detection systems and applications. Various embodiments are disclosed.
摘要:
A filter array for a multi-resolution multi-spectral camera system is described which not only captures 2D images at multiple wavelength bands simultaneously but also at a spatial resolution that meets the demand for spatial feature extraction. The present system optimizes filter bands that provide high image contrast at the highest possible resolution to enable spatial feature extraction and other wavelength bands at lower resolution to achieve maximum number of wavelength bands (e.g. spectral resolution) for multi-spectral analysis. After determining the required spatial resolution and number of wavelength bands for spectral analysis, multiple filters are arranged in a geometric pattern with each filter being designed to have specified wavelength and spatial resolution. Physical sizes of filters differ within each filter group. This maximizes the detector usage while optimizing the trade-off between spatial resolution and spectral resolution. Filter gaps are fixed or tuned to wavelengths of interest.
摘要:
What is disclosed is a system and method for estimating color for pixels in an infrared image. In one embodiment, an infrared image is received which has been captured using a N-band infrared imaging system comprising a multi-spectral camera or a hyperspectral camera. The IR image is composed of an array of pixels with N intensity values having been collected for each pixel in the image. Then, for each pixel of interest, a search metric is used to search a database of vector samples to identify a visible-IR set which is closest to the intensity values of the IR band vector collected for the pixel. A visible vector representation is then estimated for the pixel based upon the visible portion corresponding to the closest visible-IR set. Thereafter, color coordinates for this pixel are computed from the visible vector. The method repeats for all pixels of interest in the IR image.
摘要:
What is disclosed is a system and method for identifying materials comprising an object captured in a video and for using the identified materials to track that object as it moves across the captured video scene. In one embodiment, a multi-spectral or hyper-spectral sensor is used to capture a spectral image of an object in an area of interest. Pixels in the spectral planes of the spectral images are analyzed to identify a material comprising objects in that area of interest. A location of each of the identified objects is provided to an imaging sensor which then proceeds to track the objects as they move through a scene. Various embodiments are disclosed.
摘要:
What is disclosed is a system and method for monitoring respiration of a subject or subject of interest using a thermal imaging system with single or multiple spectral bands set to a temperature range of a facial region of that person. Temperatures of extremities of the head and face are used to locate facial features in the captured thermal images, i.e., nose and mouth, which are associated with respiration. The RGB signals obtained from the camera are plotted to obtain a respiration pattern. From the respiration pattern, a rate of respiration is obtained. The system includes display and communication interfaces wherein alerts can be activated if the respiration rate falls outside a level of acceptability. The teachings hereof find their uses in an array of devices such as, for example, devices which monitor the respiration of an infant to signal the onset of a respiratory problem or failure.
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 estimating a respiration rate by analyzing distortions in reflections of structured illumination patterns captured in a video containing a view of a subject's thoracic region. In one embodiment, a video of a target region of a body of a subject of interest is received. Video image frames are processed to estimate 3D time-series data for the target region. As more fully disclosed herein, the subject's respiration rate is estimated from the 3D time-series data. Measurements can be acquired under a diverse set of lighting conditions. The teachings hereof provide a non-contact approach to patient respiratory function monitoring that is useful for intensive care units and for monitoring at homes, and which aid in the detection of sudden deterioration of physiological conditions due to changes in respiration rates. The teachings hereof provide an effective tool for non-contact respiratory function study and analysis.
摘要:
What is disclosed is a system and method for enabling hybrid video capture of a scene being illuminated with structured and unstructured illumination sources over a wavelength range of interest that significantly intersects with each other. In one embodiment, the present system comprises a video capture device for capturing video of a scene being actively illuminated by both a structured and unstructured illumination source; a controller for controlling a manipulation of at least one structured and at least one unstructured illumination sources during capture of the video by the video capture device; and a processor in communication with the controller, the processor executing machine readable program instructions effectuating the manipulation. Various embodiments are disclosed.
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.