How Contactless rPPG Extracts Blood Pulsation

Every heartbeat pushes oxygenated blood through facial capillaries. Hemoglobin absorbs 540nm green light more strongly than surrounding tissue, producing sub-pixel color changes at 60 frames per second.

Test Live Camera Scan Integrate SDK

Optical Pipeline

Four steps from pixels to pulse.

Standard RGB video passes through four on-device signal stages before any clinical metric is computed.

Stage 01 · Region Isolation

Facial Mesh & ROI

Tracks 468 facial landmarks to isolate capillary-dense cheek and forehead zones while ignoring blinking, glasses, or facial hair.

Stage 02 · Signal Separation

POS & CHROM Math

Uses Plane-Orthogonal-to-Skin (POS) projection to remove room lighting flicker and subtle head motion from the 540nm pulse signal.

Stage 03 · Waveform

Pulse Reconstruction

Reconstructs arterial pulse wave morphology, resolving systolic peaks, dicrotic notches, and millisecond inter-beat intervals.

Stage 04 · Clinical Output

Vital Sign Derivation

Converts verified waveforms into Heart Rate, HRV (SDNN), Pulse Transit Blood Pressure trends, SpO2, and Respiration Rate.

Optical Specs

Designed for everyday laptop webcams and smartphone front cameras.

Camera inputStandard 720p / 1080p RGB
Frame rate24 – 120 FPS
Skin tone supportFitzpatrick Types I – VI
Scan window30 seconds
Head rotation tolerance±15°
Signal-to-noise ratio> 18.5 dB

Zero-Retention Edge

No raw facial video ever leaves the user's browser or mobile device.

Video stored0 bytes (discarded per frame)
Compute locationClient-side on-device
RuntimesWebAssembly / CoreML / NNAPI
Transport securityAES-256-GCM encrypted JSON
Privacy postureHIPAA BAA & GDPR Art. 9 ready

Clinical Benchmarks

Measured against medical hardware.

Evaluated across multi-center cohorts representing diverse ages, Fitzpatrick I–VI skin tones, and clinic lighting.

Metric	Medical Reference	Optical Method	Accuracy
Resting Heart Rate	12-Lead Holter ECG	540nm facial rPPG	r = 0.985 · RMSE 1.9 BPM
HRV (SDNN)	Clinical ECG Lead II	Inter-beat interval timing	r = 0.942 · Error < 4.8 ms
Blood Pressure Est.	Arm Sphygmomanometer	Pulse transit wave morphology	AAMI MAE < 5 mmHg
Blood Oxygen (SpO2)	Fingertip Pulse Oximeter	Dual-wavelength ratio	RMSD < 1.8% (90–100%)
Respiration Rate	Chest Impedance Strap	Respiratory sinus arrhythmia	r = 0.968 · MAE 0.9 BrPM