Anti sound

[Feitelijk]

As a spinoff from the SG firmware discussion anout sound levels:

I haven't had a lot of feedback on it yet so interested to know what people think, if we need further tuning of the levels etc

Just thinking here, but would there be a possibility of anti-sound?
Get the output of the audio system and subtract that from the microphone input to get a minimum RMS?

Probably too much for one processor though, but perhaps a future feature?

 

[Street Guardian USA]

As a spinoff from the SG firmware discussion anout sound levels:

For those wondering, the SG9665GC firmware has new Low/Medium/High for gain control on the Mic. (beta firmware) Those that listen to music very loud can use the medium setting to reduce the default high sensitivity a bit for a more aesthetically pleasing music recordings. (at the sacrifice of sensitivity performance, form over function so to speak)

Just thinking here, but would there be a possibility of anti-sound?
Get the output of the audio system and subtract that from the microphone input to get a minimum RMS?

Probably too much for one processor though, but perhaps a future feature?

I'm not sure I understand. "Get the output of the audio system and subtract that from the microphone input"
What do you mean but output of the audio system?

If you mean Noise Canceling, that usually needs more than one microphone. I think some real time comparison is going on. I really doubt this is in the Novatek, Ambarella, Zoran SDK (but I'll let Rick chime in)

http://www.audio-technica.com/cms/features/b3ef06fca462fcad/
"Microphone – Noise-cancelling headphones feature a miniature microphone in the earpiece that picks up ambient noise (such as traffic, air-handling systems, etc.) Noise-canceling circuitry – Electronics in the ear piece create a noise-cancelling wave that is 180° out of phase with the ambient noise."

 

[Feitelijk]

I do mean noise cancelling, but only from the audiosystem. And since you have that signal already (the output to the speakers) you would be able to cancel out the noise.

In fact you could even postprocess it on your PC by subtracting the CD track you were listening to to boost the external sounds. Great, I will try this myself!

 

[jokiin]

I do mean noise cancelling, but only from the audiosystem. And since you have that signal already (the output to the speakers) you would be able to cancel out the noise.

In fact you could even postprocess it on your PC by subtracting the CD track you were listening to to boost the external sounds. Great, I will try this myself!

don't think we can do what you're suggesting but interested in your experiments to see how that goes

 

[DT MI]

I do mean noise cancelling, but only from the audiosystem. And since you have that signal already (the output to the speakers) you would be able to cancel out the noise....

It seems to me that in order to do this there would have to be a direct connections from the camera to the audio system (not just a single speaker, but all channels) in order to differentiate the audio system output from the other ambient sounds in the cabin.

 

[Dashmellow]

A Mobius camera might be an interesting candidate for experimentation with noise cancelling as you can output the audio signal separately using the available wiring harness.