1 /* 2 * Copyright (c) 2011-2015, Intel Corporation 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without modification, 6 * are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, this 9 * list of conditions and the following disclaimer. 10 * 11 * 2. Redistributions in binary form must reproduce the above copyright notice, 12 * this list of conditions and the following disclaimer in the documentation and/or 13 * other materials provided with the distribution. 14 * 15 * 3. Neither the name of the copyright holder nor the names of its contributors 16 * may be used to endorse or promote products derived from this software without 17 * specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 21 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 22 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR 23 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 26 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 28 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #pragma once 32 33 #include "LinearParameterAdaptation.h" 34 35 /** 36 * This class is used to perform a logarithmic adapation of type: 37 * (slopeNumerator / slopeDenominator) * log(parameter) + offset 38 * Since log(x) == -INFINITY , we can define FloorValue as a 39 * x -> 0 40 * a lower bound limit for the adaptation 41 */ 42 class CLogarithmicParameterAdaptation : public CLinearParameterAdaptation 43 { 44 public: 45 CLogarithmicParameterAdaptation(); 46 47 /** 48 * Conversions must satisfy the following: f(f'(a)) = a 49 * Let f=fromUserValue and f'=toUserValue 50 * if y = f(log(x)/log(base)), then 51 * f'(y) * log(base) = log (x) 52 * exp(f'(y)*log(base)) = x 53 */ 54 virtual int64_t fromUserValue(double dValue) const; 55 virtual double toUserValue(int64_t iValue) const; 56 57 virtual void showProperties(std::string& strResult) const; 58 59 virtual bool fromXml(const CXmlElement& xmlElement, CXmlSerializingContext& serializingContext); 60 private: 61 /** 62 * _dLogarithmBase characterizes the new logarithm logB(x) with 63 * the following property: logB(x) = log(x) / log(_dLogarithmBase). 64 * log being the base-e logarithm. 65 */ 66 double _dLogarithmBase; 67 /** 68 * _dFloorValue reflects the lower bound for volume attenuation 69 */ 70 double _dFloorValue; 71 }; 72