spectrum.h Example File
multimedia/spectrum/app/spectrum.h/**************************************************************************** ** ** Copyright (C) 2017 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, you may use this file under the terms of the BSD license ** as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of The Qt Company Ltd nor the names of its ** contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/#ifndef SPECTRUM_H #define SPECTRUM_H #include <qglobal.h> #include "utils.h" #include "fftreal_wrapper.h" // For FFTLengthPowerOfTwo //----------------------------------------------------------------------------- // Constants //----------------------------------------------------------------------------- // Number of audio samples used to calculate the frequency spectrum const int SpectrumLengthSamples = PowerOfTwo<FFTLengthPowerOfTwo>::Result; // Number of bands in the frequency spectrum const int SpectrumNumBands = 10; // Lower bound of first band in the spectrum const qreal SpectrumLowFreq = 0.0; // Hz // Upper band of last band in the spectrum const qreal SpectrumHighFreq = 1000.0; // Hz // Waveform window size in microseconds const qint64 WaveformWindowDuration = 500 * 1000; // Length of waveform tiles in bytes // Ideally, these would match the QAudio*::bufferSize(), but that isn't // available until some time after QAudio*::start() has been called, and we // need this value in order to initialize the waveform display. // We therefore just choose a sensible value. const int WaveformTileLength = 4096; // Fudge factor used to calculate the spectrum bar heights const qreal SpectrumAnalyserMultiplier = 0.15; // Disable message timeout const int NullMessageTimeout = -1; //----------------------------------------------------------------------------- // Types and data structures //----------------------------------------------------------------------------- enum WindowFunction { NoWindow, HannWindow }; const WindowFunction DefaultWindowFunction = HannWindow; struct Tone { Tone(qreal freq = 0.0, qreal amp = 0.0) : frequency(freq), amplitude(amp) { } // Start and end frequencies for swept tone generation qreal frequency; // Amplitude in range [0.0, 1.0] qreal amplitude; }; struct SweptTone { SweptTone(qreal start = 0.0, qreal end = 0.0, qreal amp = 0.0) : startFreq(start), endFreq(end), amplitude(amp) { Q_ASSERT(end >= start); } SweptTone(const Tone &tone) : startFreq(tone.frequency), endFreq(tone.frequency), amplitude(tone.amplitude) { } // Start and end frequencies for swept tone generation qreal startFreq; qreal endFreq; // Amplitude in range [0.0, 1.0] qreal amplitude; }; // Handle some dependencies between macros defined in the .pro file #ifdef DISABLE_WAVEFORM #undef SUPERIMPOSE_PROGRESS_ON_WAVEFORM #endif #endif // SPECTRUM_H
© 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.