Biometric specific stuffs

Fingerprint Patterns

• Ridges

• Singularities (Whorl, loop, arch)

• Minutiae (terminations, bifurcations)

Fingerprint challenges

• Pressure / skin deformation

• Image quality and forensic use

• Skin condition

• Legal issues

• spoofing

Fingerprint pressure correction

Finger pressure against sensor not uniform, but decreases moving from centre towards the borders

• Close-contact region = high pressure, surface friction doesn’t allow skin slippage

• Transitional region = elastic distortion produced to combine the other regions

• External region = low pressure allows skin to be dragged by finger movement

Face recognition challenges

-            Lighting / illumination

-            Viewpoint

-            Occlusion

-            Resolution

-            Facial expression

-            Aging

-            Make-up / cosmetics

Gait Applications, advantages, challenges

Applications

-            Security / surveillance

-            Immigration

-            Forensics

-            Medicine

 

Advantages

-            Perceivable at distance

-            Hard to disguise

 

Challenges

-            Clothing

-            Carrying objects

-            Viewpoint variation

-            Walking speed

Gait - Existing silhouette descriptions

-            Temporal symmetry

-            Velocity moments

-            Unwrapped silhouette

-            Average silhouette (most popular)

Gait – Modelling movement techniques

-            Pendular thigh motion model

-            Coupled and forced oscillator

-            Anatomically guided skeleton

Iris advantages and problems

Advantages

-            Uniqueness

-            Stable over lifetime

-            Non-contact

 

Problems

-            Lighting

-            Eyebrows

-            Eyelashes

-            Eyelids

-            Peculiarities

Palm features

-            Principal lines (NU)

-            Wrinkles (NU)

-            Texture

-            Palm shape

-            Minutiae-points

Palm main techniques

-            Gabor

-            Hamming distance for matching

-            Eigenpalms

-            Multi-modal extraction

Palm challenges

-            Incorrect placement

-            Illumination

-            Time-based changes