This paper proposes an idea that treats multi-beam bathymetric sonar data as images.

Image interpolation, textual analysis and image registration, are tested using actual and synthesized multi-beam bathymetric data.

Four image texture features obtained from gray level co-occurrence matrix are integrated into six terrain navigability parameters. An underwater terrain feature vector is then defined.

Simulation results suggest that the method is capable of providing reliable position fixes when signal to noise ratio is under 2 dB.

The method is shown to be robust to image rotation and scale variance which means it is not sensitive to direction errors, and the distance between the vehicle and the bottom may vary.

When the image resolution is 1 m²/pixel and the scanning step is 1 m/move, accuracy of the method can be as high as 1 m in suitable terrains.