In this paper, a methodology for ROI extraction in INDT using multi-resolution analysis is proposed.Complementary, both local procedures Harris operator and gradient direction are used.The proposed methodology is tested using three CFRP specimens having complex shapes and defects at different depths.Besides, another two specimens are considered, which are made of PlexiglasTM and aluminum with circular flat bottom holes at different depths.The results show that the proposed methodology is invariant to the material or defect shape among considered plates, moreover the methodology only has two parameters with no dependency of the variable features of the inspected object.