As a new AudioMoth owner interested in recording bats, I'm a bit confused as to how to use the amplitude threshold feature in Configuration App 1.3.0.
Firstly, how best to expand the T-suffixed output files? I couldn't get the Expand Recordings utility of the configuration app to work with files on the SD card itself (I was getting error messages to the effect that a note field couldn't be found). After I copied all the 'thresholded' output 'T-files' onto my PC, I managed to get Expand Recordings to generate a set of expanded files without the T-suffix from them, but the utility put them in the same folder as the unexpanded T-files. Presumably I wouldn't want to process both versions of the files, so isn't that rather inconvenient?
Are you anticipating that most users will be able to process the T-files without expanding them, and that expansion would be done only on individual files when needed? Or should I always expand T-files before processing?
Which brings me to my second question of how to interpret T-files that have not been expanded. (I was recording 55-s files over 7 hours, and using Kaleidoscope to view them after initial auto-IDing. I found it quite tricky to find my place when comparing calls before and after expansion.) Is it valid to measure Time Between Calls in such files? What criteria does the amplitude threshold feature use to cut out short gaps, even between calls in a single pass?
Thanks for following up about this. We'll check the error message when you write to an SD card that is write protected and make sure that the warning message is clearer.
Hi, Have you seen the white paper on the amplitude threshold here - https://github.com/OpenAcousticDevices/White-Papers/blob/master/Using_AudioMoth_with_Filtering_and_Amplitude_Threshold_Recording.pdf. There is no single work flow in mind as it depends on the use case. In some applications, such as voice recording, it is not necessary to expand the files at all as you only want the parts with sound, and the timings aren't important. If analysing bat recordings you are probably interested in the inter-call spacing so should expand the files to restore these. In the expanded files the timings between any events is precisely what it would have been if you recorded continuously without the threshold. Can you describe the problem you had expanding the files in more detail. If there was an error message, there should also have been an error log generated on the SD card. Do you have that file? Alex