---
title: "2.2 Quality-Gated Camera Mode – Android App"
description: "| ****Brightness**** | 30 – 230 (0–255 scale) | Under- and over-exposure | | ****Contrast**** | Score ≥ 30 | Flat, low-detail images | | ****Pupil confidence**** | ≥ 30% | Frame contains a detectable pupil | | ****Centre offset****…"
url: "https://cnri.edu/docs/2-2-quality-gated-camera-mode-android-app/"
updated: "2026-03-24"
category: Capturing Eye Images
---

# 2.2 Quality-Gated Camera Mode – Android App

| ****Brightness**** | 30 – 230 (0–255 scale) | Under- and over-exposure |

| ****Contrast**** | Score ≥ 30 | Flat, low-detail images |

| ****Pupil confidence**** | ≥ 30% | Frame contains a detectable pupil |

| ****Centre offset**** | ≤ 25% of frame | Pupil not centered enough |

****Status indicators****

- 🔴 Red border + live feedback message — one or more criteria failing; hold still and adjust position

- 🟡 Amber — borderline; minor adjustment needed

- 🟢 Green border — all criteria met; photo is captured automatically

****"Not an Eye" rejection****

Even after automatic capture, a secondary AI check confirms the image contains an iris/pupil. If a non-eye image is detected (fingers, floor, clothing), a warning dialog appears with the option to retake.

****Tips for best results****

- Stabilize the device — even small hand movement drops sharpness below threshold.

- Ensure even lighting; avoid direct sunlight on one side.

- Position the iris in the center of the frame before getting close.

- Allow 2–3 seconds for the auto-exposure to settle after moving the camera.