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50 
51 #ifndef SPECTRUM_H
52 #define SPECTRUM_H
53 
54 #include <qglobal.h>
55 #include "utils.h"
56 #include "fftreal_wrapper.h" // For FFTLengthPowerOfTwo
57 
58 //-----------------------------------------------------------------------------
59 // Constants
60 //-----------------------------------------------------------------------------
61 
62 // Number of audio samples used to calculate the frequency spectrum
63 const int    SpectrumLengthSamples  = PowerOfTwo<FFTLengthPowerOfTwo>::Result;
64 
65 // Number of bands in the frequency spectrum
66 const int    SpectrumNumBands       = 10;
67 
68 // Lower bound of first band in the spectrum
69 const qreal  SpectrumLowFreq        = 0.0; // Hz
70 
71 // Upper band of last band in the spectrum
72 const qreal  SpectrumHighFreq       = 1000.0; // Hz
73 
74 // Waveform window size in microseconds
75 const qint64 WaveformWindowDuration = 500 * 1000;
76 
77 // Length of waveform tiles in bytes
78 // Ideally, these would match the QAudio*::bufferSize(), but that isn't
79 // available until some time after QAudio*::start() has been called, and we
80 // need this value in order to initialize the waveform display.
81 // We therefore just choose a sensible value.
82 const int   WaveformTileLength      = 4096;
83 
84 // Fudge factor used to calculate the spectrum bar heights
85 const qreal SpectrumAnalyserMultiplier = 0.15;
86 
87 // Disable message timeout
88 const int   NullMessageTimeout      = -1;
89 
90 
91 //-----------------------------------------------------------------------------
92 // Types and data structures
93 //-----------------------------------------------------------------------------
94 
95 enum WindowFunction {
96     NoWindow,
97     HannWindow
98 };
99 
100 const WindowFunction DefaultWindowFunction = HannWindow;
101 
102 struct Tone
103 {
104     Tone(qreal freq = 0.0, qreal amp = 0.0)
frequencyTone105     :   frequency(freq), amplitude(amp)
106     { }
107 
108     // Start and end frequencies for swept tone generation
109     qreal   frequency;
110 
111     // Amplitude in range [0.0, 1.0]
112     qreal   amplitude;
113 };
114 
115 struct SweptTone
116 {
117     SweptTone(qreal start = 0.0, qreal end = 0.0, qreal amp = 0.0)
startFreqSweptTone118     :   startFreq(start), endFreq(end), amplitude(amp)
119     { Q_ASSERT(end >= start); }
120 
SweptToneSweptTone121     SweptTone(const Tone &tone)
122     :   startFreq(tone.frequency), endFreq(tone.frequency), amplitude(tone.amplitude)
123     { }
124 
125     // Start and end frequencies for swept tone generation
126     qreal   startFreq;
127     qreal   endFreq;
128 
129     // Amplitude in range [0.0, 1.0]
130     qreal   amplitude;
131 };
132 
133 // Handle some dependencies between macros defined in the .pro file
134 
135 #ifdef DISABLE_WAVEFORM
136 #undef SUPERIMPOSE_PROGRESS_ON_WAVEFORM
137 #endif
138 
139 #endif // SPECTRUM_H
140 
141