Hydrophonitor

A software package to record audio and related metadata from a configuration of hydrophones.

For setup instructions, see setup.md.

Overview

Module	Description
audio-logger	Receive an audio signal from the DAC and write it on disk in .wav format.
gps-logger	Record position and time of the device in .csv format.
depth-logger	Record depth of the device and save it in .csv format.
*lcd-display	Provide information on the device's LCD screen
*device-controls	Provide device control using physical buttons.

*) todo, not implemented yet

Data Formats

Type	Output file format	Output file name	Output structure	Content
Audio Data	.wav	_audio.wav	Each recorded chunk will be written to its own file in audio folder	Wav audio data, configuration defined in XXX
GPS Data	.csv	_gps.wav	All data written to a single file	Csv data with following fields: GPS time UTC, latitude, longitude, speed, satellites in view
Depth data	.csv	_depth.wav	All data written to a single file	Csv data with following fields: date and time, voltage of depth sensor (V), depth (m)
Log data	.txt	_log.txt	All data written to a single file	Text file where each entry contains the following: date and time, process that writes the entry, logged information

Output Locations

The location for the output directories is defined by a configurable value OUTPUT_PATH in hydrophonitor-config.txt. If directories along this path do not exist, they will be created. If an error occurs or the location is not writable, output will be written to the default location (DEFAULT_OUTPUT_PATH in hydrophonitor-config.txt) instead.

SSD card mounting is not yet configured in the setup.

A recording session starts when the Raspberry Pi is turned on or booted, and ends on shutdown. Each session will have its output written in its own directory that will be named _recordings.