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Diffstat (limited to 'media/sphinxbase/src/libsphinxbase/fe/fe_warp_piecewise_linear.c')
| -rw-r--r-- | media/sphinxbase/src/libsphinxbase/fe/fe_warp_piecewise_linear.c | 223 |
1 files changed, 0 insertions, 223 deletions
diff --git a/media/sphinxbase/src/libsphinxbase/fe/fe_warp_piecewise_linear.c b/media/sphinxbase/src/libsphinxbase/fe/fe_warp_piecewise_linear.c deleted file mode 100644 index 34570120f..000000000 --- a/media/sphinxbase/src/libsphinxbase/fe/fe_warp_piecewise_linear.c +++ /dev/null @@ -1,223 +0,0 @@ -/* -*- c-basic-offset: 4; indent-tabs-mode: nil -*- */ -/* ==================================================================== - * Copyright (c) 2006 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. - * - * ==================================================================== - * - */ -/********************************************************************* - * - * File: fe_warp_piecewise_linear.c - * - * Description: - * - * Warp the frequency axis according to an piecewise linear - * function. The function is linear up to a frequency F, where - * the slope changes so that the Nyquist frequency in the warped - * axis maps to the Nyquist frequency in the unwarped. - * - * w' = a * w, w < F - * w' = a' * w + b, W > F - * w'(0) = 0 - * w'(F) = F - * w'(Nyq) = Nyq - * - *********************************************************************/ - -/* static char rcsid[] = "@(#)$Id: fe_warp_piecewise_linear.c,v 1.2 2006/02/17 00:31:34 egouvea Exp $"; */ - -#include <stdio.h> -#include <stdlib.h> -#include <math.h> -#include <string.h> - -#ifdef _MSC_VER -#pragma warning (disable: 4996) -#endif - -#include "sphinxbase/strfuncs.h" -#include "sphinxbase/err.h" - -#include "fe_warp.h" -#include "fe_warp_piecewise_linear.h" - -#define N_PARAM 2 -#define YES 1 -#define NO 0 - -/* - * params[0] : a - * params[1] : F (the non-differentiable point) - */ -static float params[N_PARAM] = { 1.0f, 6800.0f }; -static float final_piece[2]; -static int32 is_neutral = YES; -static char p_str[256] = ""; -static float nyquist_frequency = 0.0f; - - -const char * -fe_warp_piecewise_linear_doc() -{ - return "piecewise_linear :== < w' = a * w, w < F >"; -} - -uint32 -fe_warp_piecewise_linear_id() -{ - return FE_WARP_ID_PIECEWISE_LINEAR; -} - -uint32 -fe_warp_piecewise_linear_n_param() -{ - return N_PARAM; -} - -void -fe_warp_piecewise_linear_set_parameters(char const *param_str, - float sampling_rate) -{ - char *tok; - char *seps = " \t"; - char temp_param_str[256]; - int param_index = 0; - - nyquist_frequency = sampling_rate / 2; - if (param_str == NULL) { - is_neutral = YES; - return; - } - /* The new parameters are the same as the current ones, so do nothing. */ - if (strcmp(param_str, p_str) == 0) { - return; - } - is_neutral = NO; - strcpy(temp_param_str, param_str); - memset(params, 0, N_PARAM * sizeof(float)); - memset(final_piece, 0, 2 * sizeof(float)); - strcpy(p_str, param_str); - /* FIXME: strtok() is not re-entrant... */ - tok = strtok(temp_param_str, seps); - while (tok != NULL) { - params[param_index++] = (float) atof_c(tok); - tok = strtok(NULL, seps); - if (param_index >= N_PARAM) { - break; - } - } - if (tok != NULL) { - E_INFO - ("Piecewise linear warping takes up to two arguments, %s ignored.\n", - tok); - } - if (params[1] < sampling_rate) { - /* Precompute these. These are the coefficients of a - * straight line that contains the points (F, aF) and (N, - * N), where a = params[0], F = params[1], N = Nyquist - * frequency. - */ - if (params[1] == 0) { - params[1] = sampling_rate * 0.85f; - } - final_piece[0] = - (nyquist_frequency - - params[0] * params[1]) / (nyquist_frequency - params[1]); - final_piece[1] = - nyquist_frequency * params[1] * (params[0] - - 1.0f) / (nyquist_frequency - - params[1]); - } - else { - memset(final_piece, 0, 2 * sizeof(float)); - } - if (params[0] == 0) { - is_neutral = YES; - E_INFO - ("Piecewise linear warping cannot have slope zero, warping not applied.\n"); - } -} - -float -fe_warp_piecewise_linear_warped_to_unwarped(float nonlinear) -{ - if (is_neutral) { - return nonlinear; - } - else { - /* linear = (nonlinear - b) / a */ - float temp; - if (nonlinear < params[0] * params[1]) { - temp = nonlinear / params[0]; - } - else { - temp = nonlinear - final_piece[1]; - temp /= final_piece[0]; - } - if (temp > nyquist_frequency) { - E_WARN - ("Warp factor %g results in frequency (%.1f) higher than Nyquist (%.1f)\n", - params[0], temp, nyquist_frequency); - } - return temp; - } -} - -float -fe_warp_piecewise_linear_unwarped_to_warped(float linear) -{ - if (is_neutral) { - return linear; - } - else { - float temp; - /* nonlinear = a * linear - b */ - if (linear < params[1]) { - temp = linear * params[0]; - } - else { - temp = final_piece[0] * linear + final_piece[1]; - } - return temp; - } -} - -void -fe_warp_piecewise_linear_print(const char *label) -{ - uint32 i; - - for (i = 0; i < N_PARAM; i++) { - printf("%s[%04u]: %6.3f ", label, i, params[i]); - } - printf("\n"); -} |