Mercurial > hg > svcore
view base/RangeMapper.cpp @ 335:02d2ad95ea52 spectrogram-cache-rejig
* Get storage advice for each cache in an FFT data server. Allows us to be
more confident about the actual memory situation and cut over from memory
to disc part way through an FFT calculation if necessary. StorageAdviser
is now a bit too optimistic though (it's too keen to allocate large numbers
of small blocks in memory).
author | Chris Cannam |
---|---|
date | Tue, 13 Nov 2007 13:54:10 +0000 |
parents | 2b40f83e7627 |
children | db8fcd280234 6f6ab834449d |
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 QMUL. 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. */ #include "RangeMapper.h" #include <cassert> #include <cmath> #include <iostream> LinearRangeMapper::LinearRangeMapper(int minpos, int maxpos, float minval, float maxval, QString unit) : m_minpos(minpos), m_maxpos(maxpos), m_minval(minval), m_maxval(maxval), m_unit(unit) { assert(m_maxval != m_minval); assert(m_maxpos != m_minpos); } int LinearRangeMapper::getPositionForValue(float value) const { int position = m_minpos + lrintf(((value - m_minval) / (m_maxval - m_minval)) * (m_maxpos - m_minpos)); if (position < m_minpos) position = m_minpos; if (position > m_maxpos) position = m_maxpos; // std::cerr << "LinearRangeMapper::getPositionForValue: " << value << " -> " // << position << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", minval " << m_minval << ", maxval " << m_maxval << ")" << std::endl; return position; } float LinearRangeMapper::getValueForPosition(int position) const { float value = m_minval + ((float(position - m_minpos) / float(m_maxpos - m_minpos)) * (m_maxval - m_minval)); if (value < m_minval) value = m_minval; if (value > m_maxval) value = m_maxval; // std::cerr << "LinearRangeMapper::getValueForPosition: " << position << " -> " // << value << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", minval " << m_minval << ", maxval " << m_maxval << ")" << std::endl; return value; } LogRangeMapper::LogRangeMapper(int minpos, int maxpos, float ratio, float minlog, QString unit) : m_minpos(minpos), m_maxpos(maxpos), m_ratio(ratio), m_minlog(minlog), m_unit(unit) { assert(m_maxpos != m_minpos); m_maxlog = (m_maxpos - m_minpos) / m_ratio + m_minlog; } int LogRangeMapper::getPositionForValue(float value) const { float mapped = m_ratio * log10(value); int position = lrintf(((mapped - m_minlog) / (m_maxlog - m_minlog)) * (m_maxpos - m_minpos)); if (position < m_minpos) position = m_minpos; if (position > m_maxpos) position = m_maxpos; // std::cerr << "LogRangeMapper::getPositionForValue: " << value << " -> " // << position << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", ratio " << m_ratio << ", minlog " << m_minlog << ")" << std::endl; return position; } float LogRangeMapper::getValueForPosition(int position) const { float value = powf(10, (position - m_minpos) / m_ratio + m_minlog); // std::cerr << "LogRangeMapper::getValueForPosition: " << position << " -> " // << value << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", ratio " << m_ratio << ", minlog " << m_minlog << ")" << std::endl; return value; }