How can find decibal sampl for audio

Iam read audio file and ineed to comput loudness sample in audio

Answer 1

[Star Strider]

See if the Signal Processing Toolbox mag2db function will do what you want.

Note that it is necessary to use the absolute value of the argument:

xdB = mag2db(abs(x));

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[Esraa abd Altoni]

Thanks another question must convert audio to frequency domaine or not

[Star Strider]

That is up to you. Use the fft function, if you want to do that.

My Answer with respect to mag2dB remains the same with respect to the fft results.

[Esraa abd Altoni]

Thank you

[Star Strider]

My pleasure!

If my Answer helped you solve your problem, please Accept it!

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[Esraa abd Altoni]

I used the following equation Y=waveread(‘audio.wav’) Db=10log10(y^2/2e-5.^2)

and the result is different from this equation Db=Mag2db(y) Why please help me

[Star Strider]

I suspect that the reason is the you are calculating one of them as y.^2/2e-5.^2 instead of simply y.^2.

[Esraa abd Altoni]

I want to get samples that contain decibels higher than 80 from this equation. Mag2db) Values are very low and negative Is there an add-on to get noisy samples over 80 db?

[Star Strider]

CConsider that:

dB80 = db2mag(80)

produces:

dB80 =
    10.0000e+003 

so multiplying them by 1E+4 or dibviding them by 1E-4 would do what you want.