00001 /* 00002 * SpanDSP - a series of DSP components for telephony 00003 * 00004 * private/time_scale.h - Time scaling for linear speech data 00005 * 00006 * Written by Steve Underwood <steveu@coppice.org> 00007 * 00008 * Copyright (C) 2004 Steve Underwood 00009 * 00010 * All rights reserved. 00011 * 00012 * This program is free software; you can redistribute it and/or modify 00013 * it under the terms of the GNU Lesser General Public License version 2.1, 00014 * as published by the Free Software Foundation. 00015 * 00016 * This program is distributed in the hope that it will be useful, 00017 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00018 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00019 * GNU Lesser General Public License for more details. 00020 * 00021 * You should have received a copy of the GNU Lesser General Public 00022 * License along with this program; if not, write to the Free Software 00023 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 00024 * 00025 * $Id: time_scale.h,v 1.1 2008/11/15 14:27:29 steveu Exp $ 00026 */ 00027 00028 #if !defined(_SPANDSP_PRIVATE_TIME_SCALE_H_) 00029 #define _SPANDSP_PRIVATE_TIME_SCALE_H_ 00030 00031 #define TIME_SCALE_MAX_SAMPLE_RATE 48000 00032 #define TIME_SCALE_MIN_PITCH 60 00033 #define TIME_SCALE_MAX_PITCH 250 00034 #define TIME_SCALE_BUF_LEN (2*TIME_SCALE_MAX_SAMPLE_RATE/TIME_SCALE_MIN_PITCH) 00035 00036 /*! Audio time scaling descriptor. */ 00037 struct time_scale_state_s 00038 { 00039 int sample_rate; 00040 int min_pitch; 00041 int max_pitch; 00042 int buf_len; 00043 float playout_rate; 00044 double rcomp; 00045 double rate_nudge; 00046 int fill; 00047 int lcp; 00048 int16_t buf[TIME_SCALE_BUF_LEN]; 00049 }; 00050 00051 #endif 00052 /*- End of file ------------------------------------------------------------*/