private void DisplayColorMap(object sender, EventArgs e)
{
// Enter a null time data for showing the ticks and label of axis
chartADC.Series["ADC0"].Points.Clear();
chartADC.Series["ADC0"].Points.AddXY(0, 0);
try
{
// Set a frequency and time width of the backimage of Chart background
float dFrq = (float)(bMapHeight / ((NFFT / 2.0f) - 1.0f));
// Get a new memory bitmap with the same size, as the picture box
bMapCurrent = new Bitmap(chartADC.Images[0].Image);
bMapNew = new Bitmap(bMapWidth, bMapHeight);
// Graphics a new graphics
Graphics grphNew = Graphics.FromImage(bMapNew);
// Shift Graphics by dxScroll
grphNew.DrawImage(bMapCurrent, new PointF(-dxScroll, 0));
// Convert FFT values into Byte range within Max. and Min.
byte[] SPLband = new byte[(NFFT / 2)];
for (int Idx = 0; Idx < (NFFT / 2); Idx++)
{
// dBA calculation
float Af;
if (cbAweight.Checked == true)
{
Af = dBA_Weight[Idx];
}
else
{
Af = 0.0f;
}
double tmpSPL = 20 * Math.Log10(FFT0[Idx]) + Af;
if (tmpSPL > MaxValue)
{
tmpSPL = MaxValue;
}
else if (tmpSPL < MinValue)
{
tmpSPL = MinValue;
}
SPLband[(NFFT / 2) - (Idx + 1)] = (byte)(Math.Floor(255 / (MinValue - MaxValue) * (tmpSPL - MaxValue)));
}
// Copy the latest data into the most-right column
for (int Idx = 0; Idx < (NFFT / 2) - 1; Idx++)
{
// Create a Rectangle for each single frequency line
RectangleF RectFrq = new RectangleF(bMapWidth - dxScroll, Idx * dFrq, dxScroll, dFrq);
// Create a linear gradient brush for a signel Rectangle
LinearGradientBrush LinearBrush = new LinearGradientBrush(RectFrq,
Color.FromArgb(SPLband[Idx], SPLband[Idx], SPLband[Idx]),
Color.FromArgb(SPLband[Idx + 1], SPLband[Idx + 1], SPLband[Idx + 1]),
LinearGradientMode.Vertical);
// Fill a color of Rectangle with the created linear gradient
grphNew.FillRectangle(LinearBrush, RectFrq);
}
// Print the bitmap with colorization
bMapNew = ColorMapClass.Colorize(bMapNew, 255, JetColorMap);
// Copy the new map into the backimage of Chart background
if (chartADC.Images.Count != 0)
{
chartADC.Images.RemoveAt(0);
}
// TO COMMENT
chartADC.Images.Add(new NamedImage("ColorMapImage", bMapNew));
chartADC.ChartAreas[0].BackImage = chartADC.Images[0].Name;
chartADC.ChartAreas[0].BackImageWrapMode = ChartImageWrapMode.Scaled;
}
catch
{
}
}
private void cbColormap_CheckedChanged(object sender, EventArgs e)
{
if (cbColormap.Checked != true)
{
// Activate and deactivate buttons and colormap scale
lbl_Yint.Enabled = true;
tb_Yint.Enabled = true;
pbColorMapScale.Visible = false;
// Initiailze a chart background
chartADC.ChartAreas[0].BackImage = "";
chartADC.ChartAreas[0].BackColor = Color.White;
// Change a chart setting for FFT
chartADC.Text = "FFT";
chartADC.ChartAreas[0].AxisX.Title = "Frequency [Hz]";
chartADC.ChartAreas[0].AxisX.Minimum = 0;
chartADC.ChartAreas[0].AxisX.Maximum = 2000;
chartADC.ChartAreas[0].AxisX.Interval = 400;
chartADC.ChartAreas[0].AxisX.MajorGrid.LineDashStyle = ChartDashStyle.Dash;
chartADC.ChartAreas[0].AxisX.MajorGrid.Interval = 200;
if (cbAweight.Checked == true)
{
chartADC.ChartAreas[0].AxisY.Title = "FFTvalue [dBA]";
}
else
{
chartADC.ChartAreas[0].AxisY.Title = "FFTvalue [dB]";
}
chartADC.ChartAreas[0].AxisY.Minimum = -60;
chartADC.ChartAreas[0].AxisY.Maximum = 0;
chartADC.ChartAreas[0].AxisY.Interval = 10;
chartADC.ChartAreas[0].AxisY.MajorGrid.LineDashStyle = ChartDashStyle.Dash;
chartADC.ChartAreas[0].AxisY.MajorGrid.Interval = 10;
// Set a scale box
tb_Ymax.Text = "0";
tb_Ymin.Text = "-60";
tb_Yint.Text = "10";
// Set a max and mion value
MaxValue = Convert.ToDouble(tb_Ymax.Text);
MinValue = Convert.ToDouble(tb_Ymin.Text);
chartADC.ChartAreas[0].AxisY.Crossing = MinValue;
}
else
{
// Activate and deactivate buttons
lbl_Yint.Enabled = false;
tb_Yint.Enabled = false;
// Initiailze a color map scale
pbColorMapScale.Visible = true;
// Create a new memory bitmap the same size as the picture box
Bitmap mapColorScale = new Bitmap(pbColorMapScale.Width, pbColorMapScale.Height);
// Create a graphsics object from our memory bitmap, so we can draw on it and clear
Graphics Canvas = Graphics.FromImage(mapColorScale);
// Create a rectangle area
Rectangle RectColorScale = new Rectangle(0, 0, pbColorMapScale.Width, pbColorMapScale.Height);
// Create a new color belnd to tell the LinearGradientBrush what colors to use and where to put them
LinearGradientBrush LinearBrush = new LinearGradientBrush(RectColorScale, Color.Black, Color.White, LinearGradientMode.Vertical);
// Pass off color blend to LinearGradientBrush to instruct it how to generate the gradient
Canvas.FillRectangle(LinearBrush, RectColorScale);
// Copy the Bitmap into the image of picture box
pbColorMapScale.Image = ColorMapClass.Colorize(mapColorScale, 255, JetColorMap);
// Get the pixel position of real plotting chart area
double PixelXmin = chartADC.ChartAreas[0].AxisX.ValueToPixelPosition(chartADC.ChartAreas[0].AxisX.Minimum);
double PixelXmax = chartADC.ChartAreas[0].AxisX.ValueToPixelPosition(chartADC.ChartAreas[0].AxisX.Maximum);
double PixelYmin = chartADC.ChartAreas[0].AxisY.ValueToPixelPosition(chartADC.ChartAreas[0].AxisY.Minimum);
double PixelYmax = chartADC.ChartAreas[0].AxisY.ValueToPixelPosition(chartADC.ChartAreas[0].AxisY.Maximum);
// Get the size of bitmap in terms of pixel number
bMapWidth = (int)Math.Abs(PixelXmax - PixelXmin);
bMapHeight = (int)Math.Abs(PixelYmax - PixelYmin);
// Change a chart setting for FFT
chartADC.Text = "Color map";
chartADC.ChartAreas[0].AxisX.Title = "Time [sec]";
chartADC.ChartAreas[0].AxisX.Minimum = 0;
chartADC.ChartAreas[0].AxisX.Maximum = (NFFT / Fs) * bMapWidth / dxScroll;
chartADC.ChartAreas[0].AxisX.Interval = 1;
chartADC.ChartAreas[0].AxisX.MajorGrid.LineDashStyle = ChartDashStyle.Dash;
chartADC.ChartAreas[0].AxisX.MajorGrid.Interval = 2;
chartADC.ChartAreas[0].AxisY.Title = "Frequency [Hz]";
chartADC.ChartAreas[0].AxisY.Minimum = 0;
chartADC.ChartAreas[0].AxisY.Maximum = 2000;
chartADC.ChartAreas[0].AxisY.Interval = 400;
chartADC.ChartAreas[0].AxisY.MajorGrid.LineDashStyle = ChartDashStyle.Dash;
chartADC.ChartAreas[0].AxisY.MajorGrid.Interval = 200;
// Set a scale box
tb_Ymax.Text = "0";
tb_Ymin.Text = "-60";
tb_Yint.Text = "10";
// Create a new memory bitmap the same size as the picture box
Bitmap bMap = new Bitmap((int)Math.Abs(PixelXmax - PixelXmin), (int)Math.Abs(PixelYmax - PixelYmin));
bMap = ColorMapClass.Colorize(bMap, 255, JetColorMap);
// Draw a backimage of Chart background
if (chartADC.Images.Count != 0)
{
chartADC.Images.RemoveAt(0);
}
chartADC.Images.Add(new NamedImage("ColorMapImage", bMap));
chartADC.ChartAreas[0].BackImage = chartADC.Images[0].Name;
chartADC.ChartAreas[0].BackImageWrapMode = ChartImageWrapMode.Scaled;
}
}
private void Form1_Load(object sender, EventArgs e)
{
// Create a x-axis time data for Chart
for (int n = 0; n < NByteTime / 2; n++)
{
TimeX[n] = n / Fs;
}
// Create a x-axis time data for Chart
for (int n = 0; n < NFFT / 2; n++)
{
FreqX[n] = (float)Fs / NFFT * n;
}
// Calculate dBA Weighting
// ref: https://en.wikipedia.org/wiki/A-weighting
dBA_Weight[0] = 0; // DC components
for (int n = 1; n < NFFT / 2; n++)
{
double FreqX2 = Math.Pow(FreqX[n], 2);
double RA = Math.Pow(12194, 2) * Math.Pow(FreqX2, 2);
double RA_den = (FreqX2 + 20.6 * 20.6)
* Math.Sqrt((FreqX2 + 107.7 * 107.7)
* (FreqX2 + 737.9 * 737.9))
* (FreqX2 + 12194 * 12194);
RA /= RA_den;
dBA_Weight[n] = (float)(20 * Math.Log10(RA) + 2.0f);
}
// Initialize a chart setting
chartADC.Text = "ADC";
chartADC.ChartAreas[0].AxisX.Title = "Time [sec]";
chartADC.ChartAreas[0].AxisX.Minimum = 0;
chartADC.ChartAreas[0].AxisX.Interval = 0.05;
chartADC.ChartAreas[0].AxisX.MajorGrid.LineDashStyle = ChartDashStyle.Dash;
chartADC.ChartAreas[0].AxisX.MajorGrid.Interval = 0.05;
chartADC.ChartAreas[0].AxisY.Title = "ADC value";
chartADC.ChartAreas[0].AxisY.Minimum = -0.05;
chartADC.ChartAreas[0].AxisY.Maximum = 0.05;
chartADC.ChartAreas[0].AxisY.Interval = 0.01;
chartADC.ChartAreas[0].AxisY.MajorGrid.LineDashStyle = ChartDashStyle.Dash;
chartADC.ChartAreas[0].AxisY.MajorGrid.Interval = 0.01;
// Initialize a colormap
JetColorMap = ColorMapClass.JetTable();
//JetColorMap = ColorMapClass.Jet(); // Uncomment, if generation of a RGB Jet Table is wished
// Get all serial port names
string[] ArrayComPortsNames = SerialPort.GetPortNames();
try
{
int index = -1;
string ComPortName = null;
do
{
index += 1;
cboPorts.Items.Add(ArrayComPortsNames[index]);
}while (!((ArrayComPortsNames[index] == ComPortName) ||
(index == ArrayComPortsNames.GetUpperBound(0))));
Array.Sort(ArrayComPortsNames);
// Get the first COM port for the text in the ComboBox
if (index == ArrayComPortsNames.GetUpperBound(0))
{
ComPortName = ArrayComPortsNames[0];
}
cboPorts.Text = ArrayComPortsNames[0];
}
catch (IndexOutOfRangeException err)
{
Console.WriteLine(err.Message);
btnConnect.Enabled = false;
}
}
