stft

Y = stft (X)
Y = stft (X, WIN_SIZE)
Y = stft (X, WIN_SIZE, INC)
Y = stft (X, WIN_SIZE, INC, NUM_COEF)
Y = stft (X, WIN_SIZE, INC, NUM_COEF, WIN_TYPE)
[Y,C] = stft (X)
[Y,C] = stft (X, WIN_SIZE)
[Y,C] = stft (X, WIN_SIZE, INC)
[Y,C] = stft (X, WIN_SIZE, INC, NUM_COEF)
[Y,C] = stft (X, WIN_SIZE, INC, NUM_COEF, WIN_TYPE)

Parameters

X:

Real scalar or vector

WIN_SIZE:

Size of the window used

INC:

Increment

WIN_TYPE:

Type of window

Description

Compute the short-time Fourier transform of the vector X with NUM_COEF coefficients by applying a window of WIN_SIZE data points and an increment of INC points.

Before computing the Fourier transform, one of the following windows is applied:

"hanning" -> win_type = 1

"hamming" -> win_type = 2

"rectangle" -> win_type = 3

The window names can be passed as strings or by the WIN_TYPE number.

The following defaults are used for unspecified arguments:WIN_SIZE= 80, INC = 24, NUM_COEF = 64, and WIN_TYPE = 1.

Y = stft (X, ...)' returns the absolute values of the Fourier coefficients according to the NUM_COEF positive frequencies.

'[Y, C] = stft (x, ...)' returns the entire STFT-matrix Y and a 3-element vector C containing the window size, increment, and window type, which is needed by the 'synthesis' function.