Please download the dossier by clicking on the dossier button x
×

Continuous cardiac pulse rate estimation from multi-channel source video data

  • US 8,855,384 B2
  • Filed: 06/20/2012
  • Issued: 10/07/2014
  • Est. Priority Date: 06/20/2012
  • Status: Active Grant
First Claim
Patent Images

1. A method for continuous cardiac pulse rate estimation from video images captured of a subject of interest being monitored for cardiac function, the method comprising:

  • receiving a time-series signal of a subject of interest being monitored for cardiac function;

    overlaying said received time-series signal with a sliding window, said sliding window defining segments of said received time-series signal for processing, each successive position of said sliding window defining a next segment of said time-series signal for processing;

    defining a seed reference signal with a frequency range that approximates a frequency range of said subject'"'"'s cardiac pulse; and

    processing segments of said received time-series signal by repeatedly;

    performing constrained source separation (cICA) on said signal segment using said seed reference signal to obtain an estimated source signal, said cICA converging on an occurrence of one of;

    an error between said estimated source signal and said seed reference signal being less than a threshold, and a pre-defined number of iterations having occurred;

    A) in response to said error being less than said threshold;

    determining a frequency of said estimated source signal as said subject'"'"'s estimated cardiac pulse rate for this time-series signal segment;

    using said estimated source signal as said seed reference signal for processing a next time-series signal segment on a next iteration; and

    shifting said sliding window to define a next segment of said time-series signal, said next segment at least partially overlapping a previous time-series signal segment defined by said window on a last iteration; and

    B) in response to said pre-defined number of iterations having occurred, performing one of;

    updating said seed reference signal by changing any of;

    a frequency, an amplitude, a phase, and a waveform of said seed reference signal, and using said updated reference signal as said seed reference signal to re-process said time-series signal segment; and

    selecting an estimated source signal obtained from having processed a previous time-series signal segment and using said selected estimated source signal as said seed reference signal to re-process said time-series signal segment.

View all claims
  • 7 Assignments
Timeline View
Assignment View
    ×
    ×