Trends for solution of identification problems in holographic non-destructive testing (HNDT)

In this contribution we give a description of two modern approaches for the solution of identification problems in HNDT. One approach uses an active strategy for the classification of fault-indicating fringe patterns that can be described by the term "Recognition by Synthesis". The other approach is more passive but uses a high amount of a-priori knowledge about the appearance of material faults in fringe patterns. The derivation of this a-priori knowledge is supported by the mathematical modeling of the connection between the visible fault indicating pattern and its cause, the hidden material fault under the surface.