HiSAS 2040 XTF Tools

Under development, useful tools to look at and convert Kongsberg HiSAS 2040 XTF imagery.

Dependencies

The project depends on numpy, pillow, matplotlib and pyxtf Some extra tools require python-opencv

pyxtf release 1.4.1 does not work, use this fork for the time being: (https://github.com/joakimsk/pyxtf)

Short summary

Synthetic aperture processing is done by proprietary Kongsberg software, output is XTF. Data encoded with unknown bit size, seems to be up to 16 bit. The full synthetic ping seems to be stored in ~13000 values to each side. It reaches ~100 meters, giving ~130 pixels per meter before resampling. We half the width by resampling, to get proper aspect ratio on the image. ~6500 pixels width.

xtf2tiff.py reads a folder containing single-channel (starboard or port only, NOT combined!) sidescan XTF. All pings in a file are concatenated, and "empty" columns are deleted. Optional processing (histogram equalization and halfing in across-track direction resolution) is done. Data is stored as a greyscale tiff with either 8 or 16 bit resolution.

Usage xtf2tiff.py

Put .xtf into "xtfs", output comes in folder "tiffs".

Run with defaults or add options for histogram equalization xtf2tiff.py -heq

Sonar image without histogram equalization:

Sonar image with histogram equalization:

Usage colorize_image.py

Change code to new .tiff. Run, output is copper_image.tiff. The colormap is defined with three colors, for the range 0-255. Thus, the input image must be uint8.

Usage concat_tiff.py

Script will try to combine all tiffs vertically. This requires the same width, which is not commonly the case now after deleting empty columns.

Usage click_crop.py

Target cropping, opens an image in full resolution. Click on an object to make an roi, saved as roi_x.png. Press q on keyboard to quit.

Usage click_crop_tk.py

Target cropping, opens an image in full resolution. Click on an object to make an roi, saved as roi_x.png, and a csv-file with ROIs.

Sample data

This project contains sample data gathered by Institute of Marine Research using a Kongsberg Munin+ 1500m AUV with a Kongsberg HiSAS 2040 synthetic aperture sonar.

The research cruise and AUV dive was arranged by the MAREANO project in international waters, spring 2024.

Attribution

This project is using some lines of code copied from pyxtf which is under MIT License.

This project has also used snippets from ChatGPT, copyright violation not intended, but please take contact if you see something violating your copyright.