Patent ID: 9693710
Date: 2017-07-04
CPC Classifications: A61B,G16H

Claim:
1. A method for determining respiration rate from a video of a subject being monitored for respiratory function, the method comprising: receiving a video of a subject being monitored for respiratory function, said video comprising a plurality of time-sequential image frames of at least one region of interest of said subject's body where a signal corresponding to respiration can be registered by at least one imaging channel of a video imaging device; extracting, from said region of interest from said plurality of image frames, features of pixels and forming vectors of length N from said extracted features; constructing a N×M video matrix of temporally sequential feature vectors, a total number of columns M in said video matrix corresponding to a time duration over which a respiration rate for said subject is to be determined; processing said video matrix to obtain a matrix of eigenvectors, said eigenvector matrix being such that principal axes of variations due to motion associated with said subject's respiration are contained in a first few eigenvectors; selecting one eigenvector from said first few eigenvectors; and extracting a respiration rate for said subject from said selected eigenvector.