1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright (c) 1993-2001 by Sun Microsystems, Inc. 24 * All rights reserved. 25 */ 26 27 #ifndef _MULTIMEDIA_AUDIOGAIN_H 28 #define _MULTIMEDIA_AUDIOGAIN_H 29 30 #include <AudioTypePcm.h> 31 32 #ifdef __cplusplus 33 extern "C" { 34 #endif 35 36 // Class to handle gain calculations 37 38 // Define bits for AudioGain::Process() type argument 39 #define AUDIO_GAIN_INSTANT (1) // Gain for level meter 40 #define AUDIO_GAIN_WEIGHTED (2) // Gain for agc 41 42 43 class AudioGain { 44 protected: 45 46 static const double LoSigInstantRange; // normalization constants 47 static const double HiSigInstantRange; 48 static const double NoSigWeight; 49 static const double LoSigWeightRange; 50 static const double HiSigWeightRange; 51 static const double PeakSig; 52 static const double DCtimeconstant; // DC offset time constant 53 54 AudioTypePcm float_convert; // used in signal processing 55 unsigned clipcnt; // clip counter 56 Double DCaverage; // weighted DC offset 57 Double instant_gain; // current (instantaneous) gain 58 Double weighted_peaksum; // peak weighted sum 59 Double weighted_sum; // running sum of squares 60 Double weighted_avgsum; // accumulated sums to averages 61 unsigned weighted_cnt; // number of sums to average 62 double *gain_cache; // weighted gains 63 Double gain_cache_size; // number of cached gains 64 65 protected: 66 // Internal processing methods 67 68 // filter DC bias 69 virtual void process_dcfilter( 70 AudioBuffer*); 71 // calculate instant gain 72 virtual void process_instant( 73 AudioBuffer*); 74 // calculate weighted gain 75 virtual void process_weighted( 76 AudioBuffer*); 77 78 public: 79 AudioGain(); // Constructor 80 virtual ~AudioGain(); // Destructor 81 82 // TRUE if conversion ok 83 virtual Boolean CanConvert( 84 const AudioHdr&) const; // type to check against 85 86 // Process new audio data 87 virtual AudioError Process( 88 AudioBuffer*, int); // buffer destroyed if not referenced! 89 virtual double InstantGain(); // Get most recent gain 90 virtual double WeightedGain(); // Get current weighted gain 91 virtual double WeightedPeak(); // Get peak weighted gain 92 virtual Boolean Clipped(); // TRUE if peak since last check 93 virtual void Flush(); // Reset state 94 }; 95 96 #ifdef __cplusplus 97 } 98 #endif 99 100 #endif /* !_MULTIMEDIA_AUDIOGAIN_H */ 101