# audspec

##### Frequency band conversion

Perform critical band analysis (see PLP), which means the reduction of the fourier frequencies of a signal's powerspectrum to a reduced number of frequency bands in an auditory frequency scale.

##### Usage

```
audspec(pspectrum, sr = 16000, nfilts = ceiling(hz2bark(sr/2)) + 1,
fbtype = c("bark", "mel", "htkmel", "fcmel"), minfreq = 0,
maxfreq = sr/2, sumpower = TRUE, bwidth = 1)
```

##### Arguments

- pspectrum
Output of

`powspec`

, matrix with the powerspectrum of each time frame in its columns.- sr
Sample rate of the original recording.

- nfilts
Number of filters/frequency bins in the auditory frequency scale.

- fbtype
Used auditory frequency scale.

- minfreq
Lowest frequency.

- maxfreq
Highest frequency.

- sumpower
If

`sumpower = TRUE`

, the frequency scale transformation is based on the powerspectrum, if`sumpower = FALSE`

, it is based on its squareroot (absolute value of the spectrum) and squared afterwards.- bwidth
Modify the width of the frequency bands.

##### Value

Matrix with the auditory spectrum of each time frame in its columns.

Weight matrix for the frequency band conversion.

##### References

Daniel P. W. Ellis: http://www.ee.columbia.edu/~dpwe/resources/matlab/rastamat/

##### See Also

##### Examples

```
# NOT RUN {
testsound <- normalize(sine(400) + sine(1000) + square(250), "16")
pspectrum <- powspec(testsound@left, testsound@samp.rate)
aspectrum <- audspec(pspectrum, testsound@samp.rate)
# }
```

*Documentation reproduced from package tuneR, version 1.3.3, License: GPL-2 | GPL-3*