Liveness Threshold

The liveness threshold is the score limit that decides whether a selfie is considered live (real) or spoofed (fake). Every selfie checked by VIDA receives a liveness score between 0 and 1. The threshold acts as the cut-off point for this score.

VIDA uses a default liveness threshold of 0.95.

• If the liveness score is < 0.95, the selfie is considered live and will be accepted.

• If the liveness score is =0.95 or >0.95, the selfie is considered spoofed and will be rejected.

Liveness Score	Result	Description
< 0.95	✅ Accepted	The selfie is recognized as live
=0.95 or >0.95	❌ Rejected	The selfie is detected as spoofed or fake

The threshold represents the balance point between security and acceptance accuracy. A score closer to 0 indicates a higher confidence that the selfie is live, while a score closer to 1 indicates stronger evidence of spoofing.

• The liveness score ranges from 0.0 to 1.0.

• VIDA’s default threshold is set at 0.95, which defines the separation between accepted and rejected selfies.

✅ Accepted Area	❌ Rejected Area
Represents selfies with a liveness score < 0.95.	Represents selfies with a liveness score =0.95 or >0.95.
These selfies are classified as live, meaning the system is confident that the image was captured from a real person.	These selfies are classified as spoofed or manipulated because the score indicates signs of possible presentation attacks or image tampering.