Computer-aided object detection in archaeological geophysics: helpful tool or mirage?
Channel: Recording Archaeology
Date: 2019-10-24

The scale of archaeological geophysics has continued to grow in the last decades. Bigger data volumes raise the question if traditional interpretation methods (manual delineation of anomalies) will continue to be sufficient, and whether computer-aided methods of archaeological object detection should not become more important. These detection algorithms do not have the same ability as human interpreters. On the other hand, manual visual inspection is time-consuming and may not be able to analyse vast data sets. Moreover, detection algorithms can analyse the data in ways beyond what is familiar or readily visible. This could make the interpreter more aware of possible biases in his manual approach. A number of object detection approaches have been developed. In this paper, the ability of a few techniques to detect wall foundations and other structures in urban Roman sites is assessed (template matching, methods based on mathematical morphology, object-based image analysis). A few observations emerge. For example, there is a difficulty to select suitable quantitative evaluation metrics, and a need to find a balance between performance, simplicity and wide applicability of detection workflows. Although in archaeological geophysics computer-aided object detection is still in its infancy, it seems beyond doubt that in the future, specific applications such as the detection of small metal objects in magnetometer and EMI data, or the identification of irregular areas with enhanced reflection strength in GPR data (possibly indicating pavements) will be used more routinely and with higher accuracy.

(Lieven Verdonck)