Page 41: of Marine Technology Magazine (April 2015)

the sea? oor with bathymetric resolution combine visual information by viewing Timely information results when an as low as 5cm x 5cm and simultaneous multiple images separately. Further, the INSAS system is employed, since the co-registered imagery resolution as low integration of information across multi- overall system may enable a human op- as 3cm x 3cm. ple human observers is often unreliable. erator to reach a conclusion about some

With high resolution INSAS it is pos- Thus, a seabed survey system that can property of the environment more rap- sible to use image fusion techniques to provide a series of single fused images idly than making decisions based upon combine the bathymetric data with the with more accurate and reliable infor- data from individual sensors operating re? ectivity data to create a true 3D rep- mation than any source image is of great at different resolutions and acoustic fre- resentation of objects on the seabed. The practical value. quencies.

ability to generate centimetre-scale res- The potential advantages of image fu- Less costly information may be ob- olution in all three dimensions has the sion using Interferometric Synthetic tained from a system using multi-image potential to provide signi? cant improve- Aperture Sonar are that information can fusion. For example, a single sensor can ments in the detection, classi? cation and be obtained more accurately, as well as be used to obtain performance that could identi? cation of small seabed objects. in less time and at a lower cost. These only otherwise be achieved using a com-

Figure 2 shows an example of a co-reg- advantages correspond to the pursuit of bination of expensive multiple sensors.

istered INSAS re? ectivity imagery and complementary, more timely and less Multi-sensor image fusion seeks to corresponding bathymetry image from a costly information. combine information from different sea trial conducted with the US Naval Complementary information from co- images to obtain more inferences than

Undersea Warfare Center, Rhode Island. registered, high resolution imagery and can be derived from a single image. It

The image clearly shows a target of in- bathymetry data enables potential new is widely recognized as a very ef? cient terest at 76 m range across track. When features in the underwater environment tool for improving overall performance merged with the 3D bathymetry, the to be perceived that perhaps are impos- in image based applications. When used dimensions of this target are quickly sible to perceive using just an individual with Interferometric Synthetic Aperture determined, enabling single-pass detec- data source. Multiple sensors providing Sonar it enables ultra high resolution tion, classi? cation and identi? cation of redundant information can also serve to seabed mapping operations to be carried the target of interest; it is an abandoned increase reliability in the case of sensor out in a more timely and cost-effective lobster pot. error or failure. manner.

Image Fusion is a process of combin- ing the relevant information from a set of images of the same scene, into a sin- gle image, wherein the resultant fused image will be more informative and complete than any of the input images.

One of the goals of image fusion is to create a single enhanced image more suitable for the purpose of human visual “Deep Blue Vector” SS260 Series perception, object detection and target

Deep Water Pan & Tilt with Internal 19 Bit Absolute Positioning recognition. 15-30 VCD

The reliability and overall detail of the 1.2A-1.3A per axis image is increased, because of the ad- 100mA-1.3A per axis ditional information. Image fusion has 60 ft-lb (81.35 Nm) 150lbs (68kg) become a common term used within 0.1 to 20 deg/sec medical diagnostics and treatment. The 19 bit term is used when multiple images of 0 0.01 0 a patient are registered and overlaid or 0.001

RS-485 or RS-232 merged to provide additional informa-

Customer selectable tion. The utilization of Interferometric

Synthetic Aperture Sonar to generate

This Uniquely powerful, electrically driven, high torque 2 axis positioning high resolution 3D digital terrain mod- 0 device has a single turn resolution of 0.001 (precision of movement) and els and maps of the seabed is an ideal 0 the repeatability of position of .01. application of pixel level image fusion.

Seabed survey workloads can signi? - www.sidus-solutions.com | [email protected] cantly increase with the number of im- ages that need simultaneous monitor- +1 619 275-5533 ing. A human observer cannot reliably www.marinetechnologynews.com

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