Android PCM Bytes

Question

I am using the AudioRecord class to analize raw pcm bytes as it comes in the mic.

So thats working nicely. Now i need convert the pcm bytes into decibel.

I h

Answer 1

The units are whatever units are used for the reference reading. In the formula, the reading is divided by the reference reading, so the units cancel out and no longer matter.

In other words, decibels is a way of comparing two things, it is not an absolute measurement. When you see it used as if it is absolute, then the comparison is with the quietest sound the average human can hear.

In our case, it is a comparison to the highest reading the device handles (thus, every other reading is negative, or less than the maximum).