lbajardsilogic@0: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
lbajardsilogic@0: 
lbajardsilogic@0: /*
lbajardsilogic@0:     Sonic Visualiser
lbajardsilogic@0:     An audio file viewer and annotation editor.
lbajardsilogic@0:     Centre for Digital Music, Queen Mary, University of London.
lbajardsilogic@0:     This file copyright 2006 Chris Cannam.
lbajardsilogic@0:     
lbajardsilogic@0:     This program is free software; you can redistribute it and/or
lbajardsilogic@0:     modify it under the terms of the GNU General Public License as
lbajardsilogic@0:     published by the Free Software Foundation; either version 2 of the
lbajardsilogic@0:     License, or (at your option) any later version.  See the file
lbajardsilogic@0:     COPYING included with this distribution for more information.
lbajardsilogic@0: */
lbajardsilogic@0: 
lbajardsilogic@0: #ifndef _LOG_RANGE_H_
lbajardsilogic@0: #define _LOG_RANGE_H_
lbajardsilogic@0: 
lbajardsilogic@0: class LogRange
lbajardsilogic@0: {
lbajardsilogic@0: public:
lbajardsilogic@0:     /**
lbajardsilogic@0:      * Map a linear range onto a logarithmic range.  min and max are
lbajardsilogic@0:      * passed as the extents of the linear range and returned as the
lbajardsilogic@0:      * extents of the logarithmic range.  thresh is the minimum value
lbajardsilogic@0:      * for the log range, to be used if the linear range spans zero.
lbajardsilogic@0:      */
lbajardsilogic@0:     static void mapRange(float &min, float &max, float thresh = -10);
lbajardsilogic@0: 
lbajardsilogic@0:     /**
lbajardsilogic@0:      * Map a value onto a logarithmic range.  This just means taking
lbajardsilogic@0:      * the base-10 log of the absolute value, or using the threshold
lbajardsilogic@0:      * value if the absolute value is zero.
lbajardsilogic@0:      */
lbajardsilogic@0:     static float map(float value, float thresh = -10);
lbajardsilogic@0: };
lbajardsilogic@0: 
lbajardsilogic@0: #endif