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mel2hz

Convert from mel scale to hertz

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Syntax

hz = mel2hz(mel)
hz = mel2hz(mel,MelStyle=style)

Description

hz = mel2hz(mel) converts values on the mel frequency scale to values in hertz.

example

hz = mel2hz(mel,MelStyle=style) specifies whether to use the Slaney-style or O'Shaughnessy-style mel scale.

Examples

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Open Live Script

Set two bounding frequencies in Hz and then convert them to the mel scale.

b = hz2mel([20,8000]);

Generate a row vector of 32 values uniformly spaced on the mel scale.

melVect = linspace(b(1),b(2),32);

Convert the row vector of values into equivalent frequencies in Hz.

hzVect = mel2hz(melVect);

Plot the two vectors for comparison. As mel values increase linearly, Hz values increase exponentially.

plot(melVect,hzVect,'o')
title('Mel vs Hz')
xlabel('Mel')
ylabel('Hz')
grid on

Figure contains an axes object. The axes object with title Mel vs Hz, xlabel Mel, ylabel Hz contains a line object which displays its values using only markers.

Input Arguments

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Input frequency on the mel scale, specified as a scalar, vector, matrix, or multidimensional array.

Data Types: single | double

Mel style, specified as "oshaughnessy" or "slaney".

Data Types: char | string

Output Arguments

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Output frequency in Hz, returned as a scalar, vector, matrix, or multidimensional array the same size as mel.

Data Types: single | double

Algorithms

The frequency conversion from the O'Shaughnessy-style mel scale to Hz uses the following formula [1]:

hz=700(10mel2595−1)

The Slaney-style mel scale follows [2]. The scale is linear with respect to Hz below 1000 Hz, and it is logarithmic above 1000 Hz.

References

[1] O'Shaughnessy, Douglas. Speech Communication: Human and Machine. Reading, MA: Addison-Wesley Publishing Company, 1987.

[2] Slaney, Malcolm. "Auditory Toolbox: A MATLAB Toolbox for Auditory Modeling Work." Technical Report, Version 2, Interval Research Corporation, 1998.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2019a

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See Also

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