text: /* -*- c-basic-offset: 4; indent-tabs-mode: nil -*- */
  /* ====================================================================
   * Copyright (c) 2013 Carnegie Mellon University.  All rights 
   * reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer. 
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 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 
   * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 
   * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY
   * NOR ITS EMPLOYEES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   *
   * ====================================================================
   *
   */
  #ifndef FE_NOISE_H
  #define FE_NOISE_H
  
  #include "fe.h"
  #include "fixpoint.h"
  #include "fe_type.h"
  
  typedef struct noise_stats_s noise_stats_t;
  
  /* Creates noisestats object */
  noise_stats_t *fe_init_noisestats(int num_filters);
  
  /* Resets collected noise statistics */
  void fe_reset_noisestats(noise_stats_t * noise_stats);
  
  /* Frees allocated data */
  void fe_free_noisestats(noise_stats_t * noise_stats);
  
  /**
   * Process frame, update noise statistics, remove noise components if needed, 
   * and return local vad decision.
   */
  void fe_track_snr(fe_t *fe, int32 *in_speech);
  
  /**
   * Updates global state based on local VAD state smoothing the estimate.
   */
  void fe_vad_hangover(fe_t *fe, mfcc_t *feat, int32 is_speech, int32 store_pcm);
  
  #endif                          /* FE_NOISE_H */
  