1 /* 2 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 #ifndef __JFXMedia__AVFSoundLevelUnit__ 27 #define __JFXMedia__AVFSoundLevelUnit__ 28 29 #include <AudioUnit/AudioUnit.h> 30 #include <Accelerate/Accelerate.h> 31 #include "AVFKernelProcessor.h" 32 #include "AUEffectBase.h" 33 34 #define kDefaultSoundLevelParam_Volume 1.0f 35 #define kDefaultSoundLevelParam_Balance 0.0f 36 37 /* 38 * This unit applies the volume/balance controls. 39 */ 40 class AVFSoundLevelUnit : public AVFKernelProcessor { 41 public: 42 AVFSoundLevelUnit() : 43 AVFKernelProcessor(), 44 mVolume(kDefaultSoundLevelParam_Volume), 45 mBalance(kDefaultSoundLevelParam_Balance) 46 {} 47 48 virtual ~AVFSoundLevelUnit() {} 49 50 virtual AUKernelBase *NewKernel(); 51 52 Float32 volume() { 53 return mVolume; 54 } 55 void setVolume(Float32 volume) { 56 if (volume < 0.0) { 57 volume = 0.0; 58 } else if (volume > 1.0) { 59 volume = 1.0; 60 } 61 mVolume = volume; 62 } 63 64 Float32 balance() { 65 return mBalance; 66 } 67 void setBalance(Float32 balance) { 68 if (balance < -1.0) { 69 balance = -1.0; 70 } else if (balance > 1.0) { 71 balance = 1.0; 72 } 73 mBalance = balance; 74 } 75 76 // For stereo (2 channel), channel 0 is left, channel 1 is right 77 Float32 CalculateChannelLevel(int channelNum, int channelCount) { 78 Float32 volume = mVolume; 79 Float32 balance = mBalance; 80 Float32 level = volume; 81 82 if (channelCount == 2) { 83 // balance is only done on stereo audio 84 if (((balance < 0.0) && channelNum == 1) || 85 ((balance > 0.0) && channelNum == 0)) { 86 // attenuate according to balance 87 balance = 1.0 - fabsf(balance); 88 level *= balance; // invert so it ramps the right direction 89 } 90 } 91 return level; 92 } 93 94 private: 95 Float32 mVolume; 96 Float32 mBalance; 97 }; 98 99 #endif /* defined(__JFXMedia__AVFSoundLevelUnit__) */