1

I want to find out the level of noise around the phone. There doesn't seem to be an easy built-in way to do this, so I've found a few examples that say to use AudioRecord to listen for a brief time and then to use a formula to get the decibel. I have a few questions that the documentation doesn't seem much to explaining though and I was wondering if you kind folk could help me understand.

  1. What's captured in the Array? AudioRecord takes an several arguments on Channel type, format and sample rate and stores that information into an array. I can see the raw numbers, but what do they actually mean?

  2. Is there a resource that your could point me to, or explain to me, on how to convert(what I assume to be) the raw audio in byte form into a decibel representation?

The part I don't understand is #1, what is actually put in the array. Any help would be appreciated.

Nicholas
  • 7,403
  • 10
  • 48
  • 76
  • Recent Techcrunch disrupt hackathalon had someone developing application using noise decibel data around you to decide where's the party. – yogsma May 24 '11 at 05:39
  • well I was just wanting to see the raw information around you for a lot of factors, I'm already using the accelerometer to look at things like magnetic fields, acceleration, etc, and wanted to try to see raw noise information. – Nicholas May 24 '11 at 05:41
  • What noise level do you want to estimate. Value in dB as perceived by human ear? I guess that. Thing is that human ear is not equally sensible to sources of different frequency. – Zelimir May 24 '11 at 07:08
  • Yeah, values in dB as perceived by humans. – Nicholas May 24 '11 at 15:34
  • Or which ever way is good. Basically I want to determine to noise level around the phone to determine if the phone can be heard or not(or how loud to play a sound). – Nicholas May 24 '11 at 17:14

1 Answers1

6

Found a great resource that converts to a 0-9 range the amplitude of the sound at the mic. SoundMeter is done by google and works well enough for my purpose.

Nicholas
  • 7,403
  • 10
  • 48
  • 76