Image processing techniques were used to enhance magnetic data generated by SQUID nondestructive evaluation of conducting plates. The process consists of low-passing filtering the acquired data with a FIR filter with order depending on the standoff distance and background noise. In addition a high-pass FIR filter is used to enhance the magnetic field disturbance due to the flaw. The technique was tested on magnetic field data generated through a dc current applied to flawed aluminum test samples, and detected by using an FR-SQUID system. It was observed that when the standoff distance exceeds 5 times the size of the flaw, image inspection is difficult. Applying the enhancement algorithm, magnetic field disturbances could be visualized at distances 10 times the size of the flaw.
