Triton Overview

Summary

There were two primary goals with the development of Triton.  The first was to provide a tool which can be used to evaluate acoustic data recorded by Acoustic Recording Packages (ARPs)[1], and more recently High-frequency Recording Packages (HARPs)[2].  These data are typically single channel, long duration (up to one year), continuous and scheduled duty-cycle time series.  The time series data are often transformed to the spectral domain for evaluation as power spectra, spectrograms and Long Term Spectral Averages (LTSA).  Triton provides the necessary tools to quickly review a large data set via an easy to use graphical user interface (GUI). 

The Second goal behind the development of Triton was to provide a basis for additional features and enhancements.  For example, event detection and classification algorithms are currently being developed for use with Triton, utilizing Triton’s data management tools and GUI. 

File Types

• Data from ARPs & HARPs, are formatted into XWAV files.  XWAV files are similar to WAV files, but also contain additional header information such as instrument location, depth, name and most importantly, time and date (see Appendix A1 + A2).
• Triton can read standard WAV files including multichannel WAV files (but it can only display one channel at a time).  WAV files are typically acoustic time series and include recording parameters like sample rate and bytes per sample. 
• Triton also works with Long-Term Spectral Average (LTSA) files.  LTSA files are generated from a collection of WAV or XWAV files by averaging spectra over a long time periods and arranging these spectra sequentially as frequency-time spectrogram plots.  In addition to providing a quick overview of long-term recordings (for example, hours to weeks can be displayed on a single plot, depending on sample rate), LTSA’s provide a quick and easy link to the finer-scale acoustic data of WAV or XWAV files by simply clicking an event of interest in the LTSA plot (see following LTSA section). 

Features

Triton can:

• Read raw HARP disks, evaluate data timing and make XWAV files
• Generate time series, spectrogram, and spectra plots from WAV and XWAV data files
• Create Long Term Spectral Average (LTSA) files from WAV or XWAV files and plot LTSA’s
• Save individual plots as WAV, XWAV, jpg, or other graphical file types
• Convert ARP *.bin, OBS, and Raw HARP data files to XWAV format
• Decimate high sample rate data files to smaller & lower sample rate XWAVs.  For example, for baleen whale call analysis. 

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[1] Wiggins, S. M., Autonomous acoustic recording packages (ARP’s) for long-term monitoring of whale sounds, Marine Technology Society Journal, vol. 37(2), pp. 13-22, 2003.

[2] Wiggins, S. M. and Hildebrand, J. A., High-frequency Acoustic Recording Package (HARP) for broad-band, long-term marine mammal monitoring. International Symposium on Underwater Technology 2007 and International Workshop on Scientific Use of Submarine Cables & Related Technologies 2007, Tokyo, Japan, Institute of Electrical and Electronics Engineers, pp. 551-557, 17-20 April, 2007.