Early tests of streaming audio from the ROV


How to get the best and easiest video recordings from the ROV?

This is cool. What is it trying to say?! ;)


Feed Me, Seymour...


Im bored, carry me to the Ocean :-)


Hi Brian:

Interesting ¡¡

Could you explain the audio graphics on the left of the window ?

May be a stupid idea .... Wouldn't it be useful providing the ROV with an Audio speaker for communication with divers ?

Audio travels quite well in water, and for divers would be nice to know what the ROV is doing, or where it is.



The audio graphic on the left is a spectrogram. The the HTML5 audio APIs you have access to an analyzer that breaks out the individual frequencies for you. The example code I am using includes algorithms for real time FFT window analysis of the audio.


Thanks for your answer Brian:

Very close to the area (a plot of Gibraltar Straight) we will explore next summer, there is a cetaceans passage that connects the Atlantic ocean and the Mediterranean.

Although our goal is a wreck, it will be very interesting to get sound records. That way, some Departments, that are now out of our project, could get involved into it.

I find very very interesting this improvement, Brian. For many projects its more sifnificantt than the video recording.

About what I said regarding sound output.

When diving with divers, I was thinking on the "pilot" for being able to inform them through a microfone and an underwater speaker.

Being able to say ... "Hey guys, give me way ¡", "Help, I'm entangled", or .. "Come, look what I've found", could be very useful.



Nice Brian,

any details of what you did? I imagine that you are using the mic in the webcam?

I have been interested in using an external hydrophone and maybe taping into the codec of the webcam. Would likely need a preamp to boost the hydrophone signal.

There is interest as well for ROV/diver communications. If we can decode/encode the systems divers use now (probably FM modulated) to allow the ROV to participate. A link from the cockpit would allow operator to diver communications.



Hi Jim:

Pleased to meet you again.

As I've said many times here, electronics is not my thing. I have only point an idea, but have not work on it.

Im now a lot into hydrodynamics and propellers design (that are my thing) and hardly have any spare time.

Anyway, the simple divers communications system is based on hydrophones-speakers, and not on RF. Nothing else than pure sound traveling through the water. Looks to be a simple thing.

Speaking through the "pilot's" PC mic, amplifying at the ROV and direct sound output to the environment.

Have not thought on th Diver to Rov communication. I used such systems a few years ago, and all of them involve using "full-helmet" scuba equipment, expensive and dangerous for novices.

Anyway, the "pilot" can see the divers, and hence could understand agreed signs. The question is how the divers could receive instructions from the "ROV operator", and that, from my point of view, can be solved by sound.

NOTE: Im following your development of the acoustic location system. Quite interesting and quite a good job.



Good to hear from you Ion.

While I haven't had time to investigate, I did see mention of uw audio communications using what I thought to be a modulated signal over a carrier wave - http://casanovasadventures.com/catalog/dive/p2074.htm#.VIJanYesYyo.

I first saw mention of this in an Open Explorer posting by Elliott Jessup:

Currently trying to figure out how to have the ROV receive the following information about the divers:

-Pulse Ox
-Gas Pressures
-PO2 of rebreather loop
-Decompression status and depth

Perhaps even receive and transmit voice communication transmitted from the diver to the ROV using a 32.768 Khz Upper Sideband receiver.




Hi Jim:

Have a look at "Jelle Stuyvaert" thesis. Quite useful for your project about Undewater communications and telemetry.

The linK:





nicely written with some complementary material to Bridget Benson's UW Modem Thesis which I have been using.



You're wellcome Jim.

Hope you can find something useful in it.

I think that only for voice, direct sound transmision through water may be the simplest solution.

As I told above, we used that system and it worked. Of course it is not a long range system, but only for a few meters around. Enough for a normal underwater use, where divers and ROVs are almost the whole time at sight.

I see it as another use of the audio streaming presented by Brian above.

For data transfer, Im with you. LW may be the best way. May be that for granting a good reception, a towed antenna could help.

2^15Hz, belongs to the 10Km wave lenght band. I think, It means that long antennas are required, like the towed ones used by real Submarines.

Today is Sunday, and I can not contact anybody at my University. Tomorrow I'll try to get in touch with the chieff of the "Naval Communications and Radio-Electronics" Dpt.(who is a friend of mine) and ask for some information regarding antenna design for a little Sub for that wavelenght.

I'll inform you.

Kind regards.


I have been trying to record video and sound using various programs and I think an opensource program called ISPY works well, however I still am not able to record sound .My setup is windows 10 laptop and openrov 2.8 standard camer, can anybody help me to recording sound with a openrov 2.8 setup with VLC ,screencastify or ISPY I cant detect a mic in any program.



I ask that question in this theme: 2.8 sound streaming
No answer.