libsent/src/wav2mfcc/ss.c File Reference

Spectral subtraction. More...

#include <sent/stddefs.h>
#include <sent/mfcc.h>

Go to the source code of this file.

Functions
static boolean	myread (void *buf, size_t unitbyte, int unitnum, FILE *fp)
	Binary read function with byte swaping (assume file is BIG ENDIAN).
float *	new_SS_load_from_file (char *filename, int *slen)
	Load a noise spectrum from file.
float *	new_SS_calculate (SP16 *wave, int wavelen, int *slen, MFCCWork *w, Value *para)
	Compute average spectrum of audio input.

---

Detailed Description

Spectral subtraction.

The actual subtraction will be performed in wav2mfcc-buffer.c and wav2mfcc-pipe.c. These functions are for estimating average spectrum of audio input, and file I/O for that.

Author:

Akinobu LEE

Date:

Thu Feb 17 17:19:54 2005

Revision

1.3

Definition in file ss.c.

---

Function Documentation

static boolean myread	(	void *	buf,
		size_t	unitbyte,
		int	unitnum,
		FILE *	fp
	)			[static]

Binary read function with byte swaping (assume file is BIG ENDIAN).

Parameters:

	buf	[out] read data
	unitbyte	[in] size of a unit in bytes
	unitnum	[in] number of unit to be read
	fp	[in] file pointer

Definition at line 45 of file ss.c.

float* new_SS_load_from_file	(	char *	filename,
		int *	slen
	)

Load a noise spectrum from file.

Parameters:

	filename	[in] path name of noise spectrum file
	slen	[out] length of the returned buffer

Returns:

a newly allocated buffer that holds the loaded noise spectrum.

Definition at line 66 of file ss.c.

Referenced by RealTimeInit(), and wav2mfcc().

float* new_SS_calculate	(	SP16 *	wave,
		int	wavelen,
		int *	slen,
		MFCCWork *	w,
		Value *	para
	)

Compute average spectrum of audio input.

This is used to estimate a noise spectrum from input samples.

Parameters:

	wave	[in] input audio data sequence
	wavelen	[in] length of above
	slen	[out] length of returned buffer
	w	[i/o] MFCC calculation work area
	para	[in] parameter

Returns:

a newly allocated buffer that contains the calculated spectrum.

Definition at line 111 of file ss.c.

Referenced by wav2mfcc().

---