public void drawSpectrogram3(String prefix, String filename, float[][] data)
{
float minDb = -65.0f;
float maxDb = 0.0f;
double numberOfSamplesX = data.Length;
double numberOfSamplesY = data[0].Length;
// set width and height
int width = (int)numberOfSamplesX;
int height = (int)numberOfSamplesY;
String filenameToSave = String.Format("C:\\{0}-{1}x{2}-{3}.png", prefix, width, height, System.IO.Path.GetFileNameWithoutExtension(filename));
System.Console.Out.WriteLine("Writing " + filenameToSave);
double horizontalScaleFactor = (double)width / numberOfSamplesX;
double verticalScaleFactor = (double)height / numberOfSamplesY;
int maxYIndex = height - 1;
// Now, you need to figure out the incremental jump between samples to adjust for the scale factor. This works out to be:
int incrementX = (int)(numberOfSamplesX / (numberOfSamplesX * horizontalScaleFactor));
if (incrementX == 0)
{
incrementX = 1;
}
int incrementY = (int)(numberOfSamplesY / (numberOfSamplesY * verticalScaleFactor));
if (incrementY == 0)
{
incrementY = 1;
}
// prepare the data
// retrieve the highest and lowest value
double maxVal = double.MinValue;
double minVal = double.MaxValue;
for (int x = 0; x < data.Length; x++)
{
for (int y = 0; y < data[x].Length; y++)
{
if (data[x][y] > maxVal)
{
maxVal = data[x][y];
}
if (data[x][y] < minVal)
{
minVal = data[x][y];
}
}
}
float maxValdB = MathUtils.AmplitudeToDecibel((float)maxVal, minDb, maxDb);
float minValdB = MathUtils.AmplitudeToDecibel((float)minVal, minDb, maxDb);
double minIntensity = Math.Abs(minVal);
double maxIntensity = maxVal + minIntensity;
System.Console.Out.WriteLine("min value: {0}", minVal);
System.Console.Out.WriteLine("max value: {0}", maxVal);
System.Console.Out.WriteLine("min value: {0} dB", minValdB);
System.Console.Out.WriteLine("max value: {0} dB", maxValdB);
System.Console.Out.WriteLine("min intensity: {0}", minIntensity);
System.Console.Out.WriteLine("max intensity: {0}", maxIntensity);
// Create the image for displaying the data.
Bitmap png = new Bitmap(width, height, PixelFormat.Format32bppArgb);
Graphics g = Graphics.FromImage(png);
Rectangle rect = new Rectangle(0, 0, width, height);
g.FillRectangle(Brushes.White, rect);
for (int i = 0; i < numberOfSamplesX; i += incrementX)
{
for (int j = 0; j < numberOfSamplesY; j += incrementY)
{
int x = (int)MathUtils.RoundDown(i * horizontalScaleFactor, 0);
int y = (int)MathUtils.RoundDown(j * verticalScaleFactor, 0);
float amplitude = data[i][j];
float dB = MathUtils.AmplitudeToDecibel(amplitude, minDb, maxDb);
int color = (int)MathUtils.ConvertAndMainainRatio(dB, minValdB, maxValdB, 0, 256);
//Color c = VB6Spectrogram.PaletteValueColor(color, 256);
Color c = VB6Spectrogram.GreyPaletteValueColor(color, 256);
png.SetPixel(x, maxYIndex - y, c);
}
}
png = ColorUtils.Colorize(png, 255, ColorUtils.ColorPaletteType.SOX);
png.Save(filenameToSave);
g.Dispose();
}
public void drawSpectrogram2(String prefix, String filename, float[][] data, double sampleRate, int numberOfSamples, double fftWindowsSize)
{
float minDb = -100.0f;
float maxDb = 0.0f;
float numberOfSamplesX = data.Length;
float numberOfSamplesY = data[0].Length;
// set width and height
int width = (int)numberOfSamplesX;
int height = (int)numberOfSamplesY;
String filenameToSave = String.Format("C:\\{0}-{1}x{2}-{3}.png", prefix, width, height, System.IO.Path.GetFileNameWithoutExtension(filename));
System.Console.Out.WriteLine("Writing " + filenameToSave);
Bitmap png = new Bitmap(width, height, PixelFormat.Format32bppArgb);
Graphics g = Graphics.FromImage(png);
Pen pen = new Pen(Color.Black, 1);
// prepare the data
// retrieve the highest and lowest value
double maxVal = double.MinValue;
double minVal = double.MaxValue;
for (int x = 0; x < data.Length; x++)
{
for (int y = 0; y < data[x].Length; y++)
{
if (data[x][y] > maxVal)
{
maxVal = data[x][y];
}
if (data[x][y] < minVal)
{
minVal = data[x][y];
}
}
}
float maxValdB = MathUtils.AmplitudeToDecibel((float)maxVal, minDb, maxDb);
float minValdB = MathUtils.AmplitudeToDecibel((float)minVal, minDb, maxDb);
Axis.drawAxis(Axis.X_AXIS, 10, 10, 0, (float)MathUtils.ConvertToTime(sampleRate, numberOfSamples), 50, width - 50, 50, false, height, g);
Axis.drawAxis(Axis.Y_AXIS, 100, 10, 20, (float)(sampleRate / 2), 50, height - 50, 50, true, height, g);
int xCoord = 1;
int oldX = 1;
for (int x = 0; x < numberOfSamplesX; x++)
{
int oldY = 1;
for (int y = 0; y < numberOfSamplesY; y++)
{
int x1 = Axis.plotValue(x + 1, 1, numberOfSamplesX + 1, 50, width - 50, false, height);
int y1 = Axis.plotValue(y + 1, 1, numberOfSamplesY + 1, 50, height - 50, true, height);
/*
* float amplitude = data[x][y];
* float dB = MathUtils.ConvertAmplitudeToDB(amplitude, minDb, maxDb);
* int color = (int) MathUtils.ConvertAndMainainRatio(dB, minValdB, maxValdB, 0, 256);
* Color c = VB6Spectrogram.PaletteValueColor(color, 256);
*/
float amplitude = data[x][y];
Color colorbw = Color.Black;
if (amplitude > 0)
{
float dB = MathUtils.AmplitudeToDecibel(amplitude, minDb, maxDb);
int colorval = (int)MathUtils.ConvertAndMainainRatio(dB, minDb, maxDb, 0, 255); // 255 is full brightness, and good for REW colors (for SOX 220 is good)
colorbw = Color.FromArgb(colorval, colorval, colorval);
}
if (x1 > 0 && x1 < width && y1 > 0 && y1 < height)
{
pen.Color = colorbw;
xCoord = x1 + 50;
g.DrawLine(pen, xCoord, height - oldY - 50, xCoord, height - y1 - 50);
oldX = x1;
oldY = y1;
}
}
}
png = ColorUtils.Colorize(png, 255, ColorUtils.ColorPaletteType.REW);
png.Save(filenameToSave);
g.Dispose();
}
