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-rw-r--r--media/sphinxbase/src/libsphinxbase/feat/agc.c227
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diff --git a/media/sphinxbase/src/libsphinxbase/feat/agc.c b/media/sphinxbase/src/libsphinxbase/feat/agc.c
deleted file mode 100644
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--- a/media/sphinxbase/src/libsphinxbase/feat/agc.c
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@@ -1,227 +0,0 @@
-/* -*- c-basic-offset: 4; indent-tabs-mode: nil -*- */
-/* ====================================================================
- * Copyright (c) 1999-2004 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.
- *
- * ====================================================================
- *
- */
-/*
- * agc.c -- Various forms of automatic gain control (AGC)
- *
- * **********************************************
- * CMU ARPA Speech Project
- *
- * Copyright (c) 1996 Carnegie Mellon University.
- * ALL RIGHTS RESERVED.
- * **********************************************
- *
- * HISTORY
- * $Log$
- * Revision 1.5 2005/06/21 19:25:41 arthchan2003
- * 1, Fixed doxygen documentation. 2, Added $ keyword.
- *
- * Revision 1.3 2005/03/30 01:22:46 archan
- * Fixed mistakes in last updates. Add
- *
- *
- * 04-Nov-95 M K Ravishankar (rkm@cs.cmu.edu) at Carnegie Mellon University
- * Created.
- */
-
-#include <string.h>
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-
-#include "sphinxbase/err.h"
-#include "sphinxbase/ckd_alloc.h"
-#include "sphinxbase/agc.h"
-
-/* NOTE! These must match the enum in agc.h */
-const char *agc_type_str[] = {
- "none",
- "max",
- "emax",
- "noise"
-};
-static const int n_agc_type_str = sizeof(agc_type_str)/sizeof(agc_type_str[0]);
-
-agc_type_t
-agc_type_from_str(const char *str)
-{
- int i;
-
- for (i = 0; i < n_agc_type_str; ++i) {
- if (0 == strcmp(str, agc_type_str[i]))
- return (agc_type_t)i;
- }
- E_FATAL("Unknown AGC type '%s'\n", str);
- return AGC_NONE;
-}
-
-agc_t *agc_init(void)
-{
- agc_t *agc;
- agc = ckd_calloc(1, sizeof(*agc));
- agc->noise_thresh = FLOAT2MFCC(2.0);
-
- return agc;
-}
-
-void agc_free(agc_t *agc)
-{
- ckd_free(agc);
-}
-
-/**
- * Normalize c0 for all frames such that max(c0) = 0.
- */
-void
-agc_max(agc_t *agc, mfcc_t **mfc, int32 n_frame)
-{
- int32 i;
-
- if (n_frame <= 0)
- return;
- agc->obs_max = mfc[0][0];
- for (i = 1; i < n_frame; i++) {
- if (mfc[i][0] > agc->obs_max) {
- agc->obs_max = mfc[i][0];
- agc->obs_frame = 1;
- }
- }
-
- E_INFO("AGCMax: obs=max= %.2f\n", agc->obs_max);
- for (i = 0; i < n_frame; i++)
- mfc[i][0] -= agc->obs_max;
-}
-
-void
-agc_emax_set(agc_t *agc, float32 m)
-{
- agc->max = FLOAT2MFCC(m);
- E_INFO("AGCEMax: max= %.2f\n", m);
-}
-
-float32
-agc_emax_get(agc_t *agc)
-{
- return MFCC2FLOAT(agc->max);
-}
-
-void
-agc_emax(agc_t *agc, mfcc_t **mfc, int32 n_frame)
-{
- int i;
-
- if (n_frame <= 0)
- return;
- for (i = 0; i < n_frame; ++i) {
- if (mfc[i][0] > agc->obs_max) {
- agc->obs_max = mfc[i][0];
- agc->obs_frame = 1;
- }
- mfc[i][0] -= agc->max;
- }
-}
-
-/* Update estimated max for next utterance */
-void
-agc_emax_update(agc_t *agc)
-{
- if (agc->obs_frame) { /* Update only if some data observed */
- agc->obs_max_sum += agc->obs_max;
- agc->obs_utt++;
-
- /* Re-estimate max over past history; decay the history */
- agc->max = agc->obs_max_sum / agc->obs_utt;
- if (agc->obs_utt == 16) {
- agc->obs_max_sum /= 2;
- agc->obs_utt = 8;
- }
- }
- E_INFO("AGCEMax: obs= %.2f, new= %.2f\n", agc->obs_max, agc->max);
-
- /* Reset the accumulators for the next utterance. */
- agc->obs_frame = 0;
- agc->obs_max = FLOAT2MFCC(-1000.0); /* Less than any real C0 value (hopefully!!) */
-}
-
-void
-agc_noise(agc_t *agc,
- mfcc_t **cep,
- int32 nfr)
-{
- mfcc_t min_energy; /* Minimum log-energy */
- mfcc_t noise_level; /* Average noise_level */
- int32 i; /* frame index */
- int32 noise_frames; /* Number of noise frames */
-
- /* Determine minimum log-energy in utterance */
- min_energy = cep[0][0];
- for (i = 0; i < nfr; ++i) {
- if (cep[i][0] < min_energy)
- min_energy = cep[i][0];
- }
-
- /* Average all frames between min_energy and min_energy + agc->noise_thresh */
- noise_frames = 0;
- noise_level = 0;
- min_energy += agc->noise_thresh;
- for (i = 0; i < nfr; ++i) {
- if (cep[i][0] < min_energy) {
- noise_level += cep[i][0];
- noise_frames++;
- }
- }
-
- if (noise_frames > 0) {
- noise_level /= noise_frames;
- E_INFO("AGC NOISE: max= %6.3f\n", MFCC2FLOAT(noise_level));
- /* Subtract noise_level from all log_energy values */
- for (i = 0; i < nfr; i++) {
- cep[i][0] -= noise_level;
- }
- }
-}
-
-void
-agc_set_threshold(agc_t *agc, float32 threshold)
-{
- agc->noise_thresh = FLOAT2MFCC(threshold);
-}
-
-float32
-agc_get_threshold(agc_t *agc)
-{
- return FLOAT2MFCC(agc->noise_thresh);
-}
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