Allow ZC file upload. [Bat related]

I record bats (Chiroptera). The recording format is ZC (".zc" file extension for zero-crossing files). The ability to upload direct evidence in the form of ZC files, would greatly improve the ease and reliability bat species identification.

A ZC file is rarely over 30KB, and typically around 10KB or 15KB. Only a very small fraction of the same information can be uploaded as graphic images, and it can take ten’s of images to even start to approximate the data inherent in a ZC file.

End the discrimination in against sound recordings. You will make many bat researchers very happy if you allow the posting of ZC files.

If ZC files are sound files, what is the difference between them and other sound file types such as WAV or MP3? Is it possible to convert to one of those?

“Discrimination” seems a bit too strong of a term to use here. Sound uploads, of wav, mp4, and m4a files, have been supported for years by iNaturalist. This is the first time I’ve fielded a request for zc file support, so it hasn’t been something on our radar. If you can, please send a zc file or to to help@inaturalist.org so we can take a look at the file. If the zc file can be converted into a file format supported by iNat, that would also be helpful to know.

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Here is an example of a bat detector:

https://batdetecting.blogspot.com/2019/07/review-of-anabat-swift-bat-detector_5.html

It can record frequencies up to 155 kHz.

I am not shure that common computers can play ultrasound, and if they can nobody can here it.

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A zero crossing file is not really a recording, it is a much smaller file that captures only some specific information related to bat calls. I don’t think you can even listen to it in any meaningful way? The only way for anyone to use that file to confirm the ID is by downloading it and analysing it in certain software. Seems to be a very different thing from the photos and recordings iNat currently supports.

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To answer some questions:

Q: If ZC files are sound files, what is the difference between them and other sound file types such as WAV or MP3?
A: ZC files are generally much smaller, and therefore use less resources. There is no advantage in converting them to WAV.or MP3.

Q: Can you send a zc file or to to help@inaturalist.org?
A: Yes will do.

Q: Can common computers can play ultrasound, and if so can people here it?

A: Yes. Virtually all non specialist computers can play ultra sound, but PCs built prior to 1984 may have problems obtaining software. Virtually all Android, iOS, and Windows phones can as well. Most bat call analysts don’t listen to ultra sound, they look at it! But it’s easy to listen to if you want, just slow down the playback.

Q; Is a zero crossing file is really a recording?

A: Yes! Anything that is recorded is a recording!

Q: Is zerocrossing (ZC) a smaller file that captures only some specific information related to bat calls?

A: Yes. Its small file size is one of it’s greatest advantages, leading to big cost savings, and is why many researchers and armatures chose it over WAV.

Q: The only way for anyone to use that file to confirm the ID is by downloading it and analysing it in certain software. Seems to be a very different thing from the photos and recordings iNat currently supports?

A: Not at all. To view photos on a PC you need to install software for viewing photos (or have someone do it for you). To view ZC files you need to install software for viewing ZC files (or have someone do it for you). See! No difference, its exactly the same! No data of any type can be viewed on a computer until you (or someone) installs software to view it. If you don’t do that, you can only look at blank screen. If you are looking at this page now, it’s because you (or someone) Installed software on your computer for viewing web pages.

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There would be an advantage if that was the only feasible way for iNaturalist to make them available for “listening” or “viewing” in a generic web browser environment, or in an Android or iOS environment. So it would still be helpful to know if ZC can be converted to WAV or MP3 formats?

Or is there a commonly available browser plug-in that supports ZC format?

To the best of my knowledge there is no common (or uncommon) plug-in that supports bat call analysis in ZC, WAV, MP3 or any other format. With heterodyne you can to some extent analyse the calls auditarily via ordinary sound recordings, but confidence will often be very low.

But you say, quote:

“if that was the only feasible way for iNaturalist to make them available for “listening” or “viewing”…”

Well yes, if that was the only way. But of course it is not the only way! I can see no reason why iRecord can’t make the files available in the same way other sites already make them available, including Facebook, my own local bat groups forum, and hundereds of thousands other sites that make files available for download.

For example, I uplad a ZC file to a post in the bat group forum. Then someone else clicks in that file and either selects “Open in…” to open it immediately in their prefered analysis software, or selects “Seave File” to save it to disk for later analysis. This is basic functionality that is implemented in at least hundereds of thousands of web sites, some of them one person operations. So I don’t see why you are making it sound dificult, or as if some plug-in were necessary.

A zero crossing file is a time/frequency plot. You can convert sound files to ZC files, but the reverse would loose all waveform and volume information. A b note of a certain octave would sound the same regardless of instrument it came from or volume it was originally played at so no one has done such an endeavor.
https://www.titley-scientific.com/us/support/faqs#Question5

I have only found demo software for free that supports it for Windows/Mac/Linux, haven’t found any web-based support for the format.

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AnalookW is free for the fully functioning version, and in my opinion is the best software for analysing ZC files. It is available from Titley Scientific, or from the URL below:

https://www.anacraft.online/analookinstaller.php

Do you just look at the spectrogram to analyze the file or is there something else you do? Would bats be identifiable from spectrograms of normal audio recordings?

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Out-of-the-box computers and web browsers come with software already installed to view the most common photo, audio, and video formats. The main issue is that a ZC file is one among many thousands of niche file formats not supported with the typical built-in software. I don’t expect iNat’s geospatial data uploader for Places to work with my Trimble SSF or COR file types, so I convert them to KML before uploading.

Perhaps there should be an “other media” allowance where files types for supporting evidence such as ZC files and other things like genetic data could be uploaded.

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I’m not interested in supporting types of evidence that cannot be viewed in a browser without installing special software, and I’m also not particularly interested in types of evidence that only a very tiny minority of users will upload. So while I don’t think we should reject the possibility of ZC file support out of hand, I would want to see these things before really even considering it:

  1. A JavaScript / node package for visualizing / playing ZC data in the browser, OR some command line tool for converting ZC files into something a browser can play, like an M4A. A cursory search didn’t turn up anything like this, so I suspect someone would have to write one.
  2. Support for this beyond a single person

FWIW, it’s not even clear to me if ZC is anything more than a proprietary or ad hoc file format used by a few companies that make bat recorders, i.e. not exactly a standard. The closest thing to a specification I could find was the source of this R module for reading ZC data, which is cool, but at present R isn’t something I’m psyched about incorporating into our server infrastructure.

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