private void CalculateAndDisplayBackground(uint[,] backgroundPixels)
{
if (backgroundPixels != null)
{
int bgWidth = backgroundPixels.GetLength(0);
int bgHeight = backgroundPixels.GetLength(1);
var bgPixels = new List <uint>();
for (int x = 0; x < bgWidth; x++)
{
for (int y = 0; y < bgHeight; y++)
{
if (m_PSFFit == null || !m_PSFFit.IsSolved ||
ImagePixel.ComputeDistance(m_PSFFit.XCenter, x + bgWidth - m_PSFFit.MatrixSize, m_PSFFit.YCenter, y + bgHeight - m_PSFFit.MatrixSize) > 3 * m_PSFFit.FWHM)
{
bgPixels.Add(backgroundPixels[x, y]);
}
}
}
bgPixels.Sort();
double background = 0;
if (bgPixels.Count > 1)
{
background = m_Bpp < 12
? bgPixels[bgPixels.Count / 2] // for 8 bit videos Median background works better
: bgPixels.Average(x => x); // for 12+bit videos average background works better
}
double residualsSquareSum = 0;
foreach (uint bgPixel in bgPixels)
{
residualsSquareSum += (background - bgPixel) * (background - bgPixel);
}
double noise = Math.Sqrt(residualsSquareSum / (bgPixels.Count - 1));
lblBackground.Text = background.ToString("0.0");
lblNoise.Text = noise.ToString("0.0");
if (m_PSFFit != null)
{
double snr = m_PSFFit.GetSNR();
lblSNR.Text = snr.ToString("0.0");
}
else
{
lblSNR.Text = "N/A";
}
if (m_PSFFit != null)
{
lblFitVariance.Text = m_PSFFit.GetVariance().ToString("0.0");
lblFWHM.Text = m_PSFFit.FWHM.ToString("0.0");
}
else
{
lblFitVariance.Text = "N/A";
lblFWHM.Text = "N/A";
}
}
else
{
lblBackground.Text = "N/A";
lblNoise.Text = "N/A";
lblSNR.Text = "N/A";
}
}