我试图让噪音的分贝,从话筒的Android手机被条记录。我能得到振幅值,并寻找下式将其转换成分贝。
I'm trying to get the decibel of noise being recored from mic on Android phone. I can get amplitude value and looking for the formula to convert it into decibel.
我用下面的MediaRecorder功能得到幅度。
I use following function of MediaRecorder to get amplitude.
mediaRecorder.getMaxAmplitude();
mediaRecorder.getMaxAmplitude() ;
在another问题我发现下面的公式。
power_db = 20 * LOG10(安培/ amp_ref);
power_db = 20 * log10(amp / amp_ref);
安培
的幅度,但不知道什么是 amp_ref
。
amp
is amplitude but not sure what's amp_ref
.
有没有人知道正确的公式?
Is there anyone knows the correct formula?
我认为这是正确的公式。 amp_ref是参考幅度
i think that is the correct formula. amp_ref is reference amplitude