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stft

PURPOSE

% Compute the short-time Fourier transform of the vector @var{x} with

SYNOPSIS

function [Y, c] = stft(X, win, inc, coef, w_type)

DESCRIPTION

```% -*- texinfo -*-
% @deftypefn {Function File} {[@var{y}, @var{c}] =} stft (@var{x}, @var{win_size}, @var{inc}, @var{num_coef}, @var{w_type})
% Compute the short-time Fourier transform of the vector @var{x} with
% @var{num_coef} coefficients by applying a window of @var{win_size} data
% points and an increment of @var{inc} points.
%
% Before computing the Fourier transform, one of the following windows
% is applied:
%
% @table @asis
% @item hanning
% w_type = 1
% @item hamming
% w_type = 2
% @item rectangle
% w_type = 3
% @end table
%
% The window names can be passed as strings or by the @var{w_type} number.
%
% If not all arguments are specified, the following defaults are used:
% @var{win_size} = 80, @var{inc} = 24, @var{num_coef} = 64, and
% @var{w_type} = 1.
%
% @code{@var{y} = stft (@var{x}, @dots{})} returns the absolute values
% of the Fourier coefficients according to the @var{num_coef} positive
% frequencies.
%
% @code{[@var{y}, @var{c}] = stft (@code{x}, @dots{})} returns the
% entire STFT-matrix @var{y} and a 3-element vector @var{c} containing
% the window size, increment, and window type, which is needed by the
% synthesis function.
% @end deftypefn```

CROSS-REFERENCE INFORMATION

This function calls:
• hamming % Return the filter coefficients of a Hamming window of length @var{m}.
• hanning % Return the filter coefficients of a Hanning window of length @var{m}.
This function is called by:

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