Mercurial > hg > svcore
view base/LogRange.h @ 369:007b01b971a6
* function rename & notes
author | Chris Cannam |
---|---|
date | Mon, 04 Feb 2008 13:35:11 +0000 |
parents | 2268963dabd1 |
children | 1405f4a2caf3 |
line wrap: on
line source
/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ /* Sonic Visualiser An audio file viewer and annotation editor. Centre for Digital Music, Queen Mary, University of London. This file copyright 2006 Chris Cannam. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. See the file COPYING included with this distribution for more information. */ #ifndef _LOG_RANGE_H_ #define _LOG_RANGE_H_ class LogRange { public: /** * Map a linear range onto a logarithmic range. min and max are * passed as the extents of the linear range and returned as the * extents of the logarithmic range. thresh is the minimum value * for the log range, to be used if the linear range spans zero. */ static void mapRange(float &min, float &max, float thresh = -10); /** * Map a value onto a logarithmic range. This just means taking * the base-10 log of the absolute value, or using the threshold * value if the absolute value is zero. */ static float map(float value, float thresh = -10); /** * Map a value from the logarithmic range back again. This just * means taking the value'th power of ten. */ static float unmap(float value); }; #endif