agc.h

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/* -*- c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* ====================================================================
 * Copyright (c) 1999-2004 Carnegie Mellon University.  All rights
 * reserved.
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 *    notice, this list of conditions and the following disclaimer. 
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 *    distribution.
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 * This work was supported in part by funding from the Defense Advanced 
 * Research Projects Agency and the National Science Foundation of the 
 * United States of America, and the CMU Sphinx Speech Consortium.
 *
 * THIS SOFTWARE IS PROVIDED BY CARNEGIE MELLON UNIVERSITY ``AS IS'' AND 
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/*
 * agc.h -- Various forms of automatic gain control (AGC)
 * 
 * **********************************************
 * CMU ARPA Speech Project
 *
 * Copyright (c) 1999 Carnegie Mellon University.
 * ALL RIGHTS RESERVED.
 * **********************************************
 * 
 * HISTORY
 * $Log$
 * Revision 1.1  2006/04/05  20:27:30  dhdfu
 * A Great Reorganzation of header files and executables
 * 
 * Revision 1.8  2005/06/21 19:25:41  arthchan2003
 * 1, Fixed doxygen documentation. 2, Added $ keyword.
 *
 * Revision 1.4  2005/06/13 04:02:56  archan
 * Fixed most doxygen-style documentation under libs3decoder.
 *
 * Revision 1.3  2005/03/30 01:22:46  archan
 * Fixed mistakes in last updates. Add
 *
 * 
 * 28-Apr-1999  M K Ravishankar (rkm@cs.cmu.edu) at Carnegie Mellon University
 *              Copied from previous version.
 */


#ifndef _S3_AGC_H_
#define _S3_AGC_H_

/* Win32/WinCE DLL gunk */
#include <sphinxbase/sphinxbase_export.h>

#include <sphinxbase/prim_type.h>
#include <sphinxbase/fe.h>

#ifdef __cplusplus
extern "C" {
#endif
#if 0
/* Fool Emacs. */
}
#endif

typedef enum agc_type_e {
    AGC_NONE = 0,
    AGC_MAX,
    AGC_EMAX,
    AGC_NOISE
} agc_type_t;

SPHINXBASE_EXPORT
agc_type_t agc_type_from_str(const char *str);

SPHINXBASE_EXPORT
extern const char *agc_type_str[];

typedef struct agc_s {
    mfcc_t max;      
    mfcc_t obs_max;  
    int32 obs_frame; 
    int32 obs_utt;   
    mfcc_t obs_max_sum;
    mfcc_t noise_thresh; 
} agc_t;

SPHINXBASE_EXPORT
agc_t *agc_init(void);

SPHINXBASE_EXPORT
void agc_free(agc_t *agc);

SPHINXBASE_EXPORT
void agc_max(agc_t *agc,        
             mfcc_t **mfc,      
             int32 n_frame      
    );

SPHINXBASE_EXPORT
void agc_emax(agc_t *agc,       
              mfcc_t **mfc,     
              int32 n_frame     
    );

SPHINXBASE_EXPORT
void agc_emax_update(agc_t *agc 
    );

SPHINXBASE_EXPORT
float32 agc_emax_get(agc_t *agc);

SPHINXBASE_EXPORT
void agc_emax_set(agc_t *agc, float32 m);

SPHINXBASE_EXPORT
void agc_noise(agc_t *agc,      
               mfcc_t **mfc,    
               int32 n_frame    
    );

SPHINXBASE_EXPORT
float32 agc_get_threshold(agc_t *agc);

SPHINXBASE_EXPORT
void agc_set_threshold(agc_t *agc, float32 threshold);


#ifdef __cplusplus
}
#endif

#endif