Capture
I attach the photo to the screening task and save it.
Engineering
How LungLens processes a capture
I kept the angle math separate from any step that tries to find landmarks. That finding step is still a stub, so a number stays research-only.
A quality pass only means the photo can continue. It is not a validated measurement. Placeholder landmarks can still produce numbers.
A guided capture setup. Photograph for context, not a clinic case.
From photo to a careful result
Each stage has one job. Finding landmarks is experimental. Clinicians already use profile-angle and depth-ratio ideas when they examine clubbing by hand [1].
- 01Capture
- 02Quality
- 03Find landmarks
- 04Measure
- 05Abstain
- 06Release
What each stage does
I can change the landmark model without rewriting the measurement math.
Quality gate
If the photo is missing, blurry, glaring, or the nail is hidden, I reject it. A pass only means the photo can continue.
Landmark finding
Today the default path is a stub. It can return placeholder points. Trained weights are still experimental.
Geometry
I compute Lovibond angle from three points, and depth ratio as a length comparison. This is ordinary vector math.
Abstention
If confidence is too low, I return Unable to assess. That cutoff is an engineering choice, not a finished clinical rule.
Release
When the path is still a stub, I do not show a clinical label in clinic tools. A technical failure must not become a reassuring finding.