Enhanced Biometric Capture Validation with SDK Match Score & Face Quality Checks

[Pragya279]

User Story: Enhanced Biometric Capture Validation with SDK Match Score & Face Quality Checks
As a Registration Operator
I want the system to show the biometric match score from the SDK along with the capture quality score, and automatically detect if the captured face image is non-smiling or low-quality
So that I can ensure the biometric is both high-quality and suitable for matching, ensuring accurate identification and a better applicant experience.

Problem / Need
Capturing a technically good biometric is not sufficient—identification accuracy depends on matchability (how well the biometric will match future samples) and image quality (clarity, lighting, pose, expression).

Operators currently see only quality scores.

They do not see matchability indicators, which help assess whether the captured biometric will perform well in deduplication or authentication.

For face capture, smiling, inconsistent lighting, tilt, or blur can make photos unusable.

The system needs to automatically detect such issues and guide operators for better captures.

This feature closes these gaps by combining Quality Score, Match Score, and Face Expression/Quality Validation.

Feature Description

1. SDK Match Score Display
   After capturing biometrics (face, fingerprint, iris), the system sends the captured sample to the configured SDK (e.g., face SDK, fingerprint matcher).

SDK returns a Matchability Score such as:

Match Score (0–1 or 0–100)

Matching Confidence Level (Low/Medium/High)

Liveness or anti-spoof checks (if supported)

The system displays this along with the standard quality score.

Output Seen by Operator:
Quality Score (clarity, sharpness, positioning)

Match Score (SDK-based matchability)

Visual indicator:

Green: Good matchability

Yellow: Acceptable

Red: Poor / unusable

2. Non-Smiling Face Detection
   Using face analytics from the SDK, the system detects:

Smile or unacceptable expressions

Mouth open

Eye closure / blink

Head tilt or rotation

If smiling or expressive face is detected:

UI shows:
“Neutral expression required. Please recapture the photo.”

3. Enhanced Face Image Quality Checks
   For face captures, the system automatically validates:

Lighting uniformity

Background consistency

Sharpness & focus

Pose correctness (frontal, straight eyes, no tilt)

Occlusions (hair, mask, glasses glare)

If the face capture is poor, the system prompts the operator to retake it.

4. Display of Combined Validation Results
   The capture screen will show:

Parameter | Displayed to Operator -- | -- Biometric Quality Score | Numeric + Pass/Fail Match Score | Numeric + Matchability rating Expression Check | Pass/Fail (e.g., “Neutral Face Required”) Photo Quality Indicators | Highlights issues: Blur / Lighting / Pose
Operators see all validations in one place.

5. Configurable Thresholds
   Quality thresholds

Minimum match score

Expression rules (strict/relaxed)

Recapture enforcement (mandatory or override-allowed)

6. Storage in Packet
   Store the quality score, match score, and face analysis metadata inside biometric packet metadata for audits and analytics.

Acceptance Criteria
AC1: System calculates and displays both quality score and SDK match score after capture.
AC2: System detects smiling or expressive faces and blocks capture until a neutral expression is provided.
AC3: System validates photo quality (lighting, focus, pose, occlusion) and prompts operator for correction.
AC4: System blocks operator from proceeding if match score < threshold (unless override enabled).
AC5: All scores and metadata are stored in the biometric packet.
AC6: Thresholds for match score and expression rules are configurable.
AC7: UI shows clear messages for each error or poor condition.
Example User Flow
Operator captures applicant’s face photo.

System calculates:

Quality score = 72 (Pass)

Match score = 48 (Below threshold 60 → Fail)

Expression: Smiling → Fail

Pose: Slight head tilt → Warning

System displays:

❌ Matchability too low. Please recapture.

❌ Neutral expression required.

⚠️ Head slightly tilted. Adjust camera.

Operator recaptures face.

New results:

Quality = 85 (Pass)

Match score = 78 (Pass)

Neutral expression (Pass)

Pose correct (Pass)

Operator proceeds.