/// <summary>
/// sets graph data
/// </summary>
public void SetAudioData(float[] audioData)
{
this.audioData = audioData;
float[] spectrumData = AudioAnalyzer.CreateSpectrumAnalysisLomont(audioData, fftWindowsSize);
float[] m_mag;
float[] m_freq;
AudioAnalyzer.PrepareSpectrumAnalysis(spectrumData, sampleRate, fftWindowsSize,
out m_mag, out m_freq, out foundMaxFrequency, out foundMaxDecibel);
bmp = AudioAnalyzer.GetSpectrumImage(ref m_mag, ref m_freq, new Size(this.Width, this.Height),
showMinFrequency, showMaxFrequency, foundMaxDecibel, foundMaxFrequency);
// force redraw
this.Invalidate();
}
/// <summary>
/// Use the FFT results to update the height and y position of the bars
/// </summary>
private void UpdateSpectrumShapes()
{
bool allZero = true;
if (DoSpectrumGraph)
{
#region Draw Spectrum Analysis Graph
float[] mag;
float[] freq;
float foundMaxFreq, foundMaxDecibel;
double sampleRate = soundPlayer.SampleRate;
int fftWindowsSize = soundPlayer.FftDataSize;
AudioAnalyzer.PrepareSpectrumAnalysis(channelData, sampleRate, fftWindowsSize, out mag, out freq, out foundMaxFreq, out foundMaxDecibel);
this.offlineBitmap = AudioAnalyzer.GetSpectrumImage(ref mag, ref freq, new Size(this.Width, this.Height), MinimumFrequency, MaximumFrequency, foundMaxDecibel, foundMaxFreq);
#endregion
}
else
{
#region Draw Bars
double fftBucketHeight = 0f;
double barHeight = 0f;
double lastPeakHeight = 0f;
double peakYPos = 0f;
double height = this.Height;
int barIndex = 0;
double peakDotHeight = Math.Max(barWidth / 2.0f, 1);
double barHeightScale = (height - peakDotHeight);
for (int i = minimumFrequencyIndex; i <= maximumFrequencyIndex; i++)
{
// If we're paused, keep drawing, but set the current height to 0 so the peaks fall.
if (!soundPlayer.IsPlaying)
{
barHeight = 0f;
}
else // Draw the maximum value for the bar's band
{
switch (BarHeightScaling)
{
case BarHeightScalingStyles.Decibel:
double dbValue = 20 * Math.Log10((double)channelData[i]);
fftBucketHeight = ((dbValue - minDBValue) / dbScale) * barHeightScale;
break;
case BarHeightScalingStyles.Linear:
fftBucketHeight = (channelData[i] * scaleFactorLinear) * barHeightScale;
break;
case BarHeightScalingStyles.Sqrt:
fftBucketHeight = (((Math.Sqrt((double)channelData[i])) * scaleFactorSqr) * barHeightScale);
break;
}
if (barHeight < fftBucketHeight)
{
barHeight = fftBucketHeight;
}
if (barHeight < 0f)
{
barHeight = 0f;
}
}
// If this is the last FFT bucket in the bar's group, draw the bar.
int currentIndexMax = IsFrequencyScaleLinear ? barIndexMax[barIndex] : barLogScaleIndexMax[barIndex];
if (i == currentIndexMax)
{
// Peaks can't surpass the height of the control.
if (barHeight > height)
{
barHeight = height;
}
if (AveragePeaks && barIndex > 0)
{
barHeight = (lastPeakHeight + barHeight) / 2;
}
peakYPos = barHeight;
if (channelPeakData[barIndex] < peakYPos)
{
channelPeakData[barIndex] = (float)peakYPos;
}
else
{
channelPeakData[barIndex] = (float)(peakYPos + (PeakFallDelay * channelPeakData[barIndex])) / ((float)(PeakFallDelay + 1));
}
double xCoord = BarSpacing + (barWidth * barIndex) + (BarSpacing * barIndex) + 1;
Rectangle barRect = barShapes[barIndex];
barRect.Y = (int)((height - 1) - barHeight);
barRect.Height = (int)barHeight;
barShapes[barIndex] = barRect;
Rectangle peakRect = peakShapes[barIndex];
peakRect.Y = (int)((height - 1) - channelPeakData[barIndex] - peakDotHeight);
peakShapes[barIndex] = peakRect;
if (channelPeakData[barIndex] > 0.05)
{
allZero = false;
}
lastPeakHeight = barHeight;
barHeight = 0f;
barIndex++;
}
}
#endregion
}
if (allZero && !soundPlayer.IsPlaying)
{
animationTimer.Stop();
}
}
