Cross-Sensor Micro-Texture Material Classification and Smartphone Acquisition do not go well together

Intrinsic, non-invasive product authentication is still
an important topic as it does not generate additional costs
during the production process. This topic is of specific interest
for medical products as non-genuine products can directly
effect the patients’ health. This work investigates micro-texture
classification as a mean of proving the authenticity of zircon
oxide blocks (for dental implants). Samples of three different
manufacturers were acquired using four smartphone devices with
a clip-on macro lens. In addition, an existing drug packaging
material database was utilized. While the intra-sensor micro-
texture classification worked well, the cross-sensor classification
results were less promising. In an attempt to track down the
limiting factors, intrinsic sensor features usually used in device
identification were investigated as well.