Opto-physiological modeling applied to photoplethysmographic cardiovascular assessment.

This paper presents opto-physiological (OP) modeling and its application in cardiovascular assessment techniques based on photoplethysmography (PPG). Existing contact point measurement techniques, i.e.

BioThreads: a novel VLIW-based chip multiprocessor for accelerating biomedical image processing applications.

We discuss BioThreads, a novel, configurable, extensible system-on-chip multiprocessor and its use in accelerating biomedical signal processing applications such as imaging photoplethysmography (IPPG). BioThreads is derived from the LE1 open-source VLIW chip multiprocessor and efficiently handles instruction, data and thread-level parallelism. In addition, it supports a novel mechanism for the dynamic creation, and allocation of software threads to uncommitted processor cores by implementing key POSIX Threads primitives directly in hardware, as custom instructions.

Noncontact imaging photoplethysmography to effectively access pulse rate variability.

Noncontact imaging photoplethysmography (PPG) can provide physiological assessment at various anatomical locations with no discomfort to the patient. However, most previous imaging PPG (iPPG) systems have been limited by a low sample frequency, which restricts their use clinically, for instance, in the assessment of pulse rate variability (PRV). In the present study, plethysmographic signals are remotely captured via an iPPG system at a rate of 200 fps.

Use of ambient light in remote photoplethysmographic systems: comparison between a high-performance camera and a low-cost webcam.

Imaging photoplethysmography (PPG) is able to capture useful physiological data remotely from a wide range of anatomical locations. Recent imaging PPG studies have concentrated on two broad research directions involving either high-performance cameras and or webcam-based systems. However, little has been reported about the difference between these two techniques, particularly in terms of their performance under illumination with ambient light.

Motion-compensated noncontact imaging photoplethysmography to monitor cardiorespiratory status during exercise.

With the advance of computer and photonics technology, imaging photoplethysmography [(PPG), iPPG] can provide comfortable and comprehensive assessment over a wide range of anatomical locations. However, motion artifact is a major drawback in current iPPG systems, particularly in the context of clinical assessment. To overcome this issue, a new artifact-reduction method consisting of planar motion compensation and blind source separation is introduced in this study.

A study of opto-physiological modeling to quantify tissue absorbance in imaging photoplethysmography.

This paper presents an opto-physiological model (OPM) to quantify the absorbance of multi-layered tissue in imaging photoplethysmography (IPPG). The approach used to generate such a model is to revise the path length of the Beer Lambert law through the Monte Carlo (MC) simulation of multi-layered tissue. The OPM can mathematically quantify the effect of optical properties on the absorbance of multilayered tissue.

Development of effective photoplethysmographic measurement techniques: from contact to non-contact and from point to imaging.

This paper provides an overview of the most recent developments in photoplethysmography (PPG). Existing contact point measurement techniques, i.e.