Creating Single-Band GeoTIFFs of Sidescan Data

Chesapeake Times, Vol 7 | October 2021 What is a Vertical GeoTIFF?? GeoTIFF is a public domain metadata standard which allows geo-referencing information to be embedded within a TIFF file (Wikipedia). Normally, the GeoTIFF format is used for geo-referenced images, where each pixel in the TIFF represents a color to display at a specified geographic location. The metadata in the TIFF encodes the geospatial information needed to render the image at the appropriate location on the earth. SonarWiz offers extensive support for exporting seafloor imagery in this format.  More recently, GeoTIFFs have been used to encode physical measurements rather than just imagery. …

Expanded CSF Sample Count Options

Chesapeake Times, Vol 6 | July 2021 Recently we’ve seen a good amount of interest in higher-resolution sidescan. Recordings can be made at 10,000 or more samples per channel, to allow for centimeter-level resolutions over relatively wide swaths. Customers want to make the most of the systems they’ve invested in and offer high-resolution deliverables. To accommodate these needs, the upcoming 7.8.0 release of SonarWiz will include some new sidescan import sample count options. Previously, sidescan files could be imported with 1024, 2048, or 4096 samples per channel. Now, a user-selectable or automatically-detected number of samples can be imported, with a …

Side Scan Drawing Improvement

Chesapeake Times, Vol 4 | January 2021This month some of CTI’s development resources have been focused on updating our Side Scan drawing routines to more accurately map samples to pixels in the display. These drawing routines and their accuracy become more important as users require higher and higher resolutions due to increasing accuracy of navigation, sonar equipment, and project requirements. Years ago placement of data had to be to the meter. Now we are looking at projects that require down to 10cm and sometimes lower. What’s the Problem?There are two main issues we have been focusing our efforts on. These issues are: Along track …

QPS and SonarWiz Streamline Sidescan Workflow

Chesapeake Times, Vol 2 | July 2020 Late last year, Chesapeake and QPS worked together on providing a simplified workflow to process sidescan data that had been collected in the Qinsy software. Raw Database (.db) files recorded in Qinsy can now be imported directly into SonarWiz, without the need for any conversion to XTF. The Qinsy Database file is a proprietary format and, in the past, required users to have the sonar files converted to XTF before processing. This approach reduces the data processing time and can remove potential errors that might occur during the conversion to XTF. Using the …

A-B Change Detection for Sidescan

By Howard Unkeles and Harold Orlinsky Creating a sidescan mosaic for a survey is easy. And doing a second survey is also easy. You can even use the same line plans, as the area is known. But what’s difficult is to find any differences between the two. A visual inspection will find new features, or if there if something moved. But imagine doing this for a huge survey area, a 1:10,000 boat sheet or an area like the Port of Los Angeles. This inspection would take a while, and subtle differences might be overlooked. In the upcoming release, we created an automated tool to analyze …