private void DisplaySelectedImage(string fileName)
{
_fits = new FITS(fileName);
if (!_headerMode)
{
Scale();
pictureBox.Image = _fits.Bitmap;
}
textBoxHeader.Text = _fits.Header.Text;
toolStripStatusLabel.Text = Path.GetFileName(fileName);
}
public FITS(FITS that)
{
Header.Bitpix = that.Header.Bitpix;
Header.Width = that.Header.Width;
Header.Height = that.Header.Height;
FileName = that.FileName;
PixelMap = new double[Header.Width * Header.Height];
for (int i = 0; i < Header.Width * Header.Height; i++)
{
PixelMap[i] = that.PixelMap[i];
}
Bitmap = new Bitmap(that.Bitmap);
Scaled = that.Scaled;
}
// scale data to bitmap. Zscale, if that is possible.
private void ZScale(FITS fits)
{
int width = fits.Header.Width;
int height = fits.Header.Height;
int size = width * height;
fits.Bitmap = new Bitmap(width, height);
float contrast = 0.25f;
int NSample = Math.Min(size / 10, 10000);
int NRows = height / 15;
int[] SubSampleX = new int[NSample];
int[] SubSampleY = new int[NSample];
double[] SubSample = new double[NSample];
double[] SubSampleSorted = new double[NSample];
Random random = new Random(DateTime.Now.Millisecond);
for (int cell = 0; cell < NSample; cell++)
{
int X = SubSampleX[cell] = random.Next(1, width - 1);
int Y = SubSampleY[cell] = random.Next(1, height - 1);
SubSample[cell] = fits.PixelMap[X + Y * width];
}
float[] tmp = new float[NSample];
SubSample.CopyTo(SubSampleSorted, 0);
Array.Sort(SubSampleSorted);
double zmin = SubSampleSorted[0];
double zmed = SubSampleSorted[NSample / 2];
double zmax = SubSampleSorted[NSample - 1];
int midPoint = NSample / 2;
double Sx = 0.5f * NSample * (NSample - 1);
double Sy = SubSampleSorted.Sum();
double Sxx = Count_Sxx(SubSampleSorted);
double Sxy = Count_Sxy(SubSampleSorted);
double a = (NSample * Sxy - Sx * Sy) / (NSample * Sxx - Sx * Sx);
double b = (Sy - a * Sx) / NSample;
a /= contrast;
double scale;
double value;
// The minimum value to use for display scaling
float z1 = Math.Max((float)fits.Min, (float)(zmed - midPoint * a));
// The maximum value to use for display scaling
float z2 = Math.Min((float)fits.Max, (float)(zmed + midPoint * a));
fits.Range = Math.Abs(z2 - z1);
if (fits.Range < float.Epsilon)
{
scale = 0.0;
}
else
{
scale = byte.MaxValue / fits.Range;
}
Color newColor;
byte byteValue;
double temp;
for (int h = 0; h < height; h++)
{
for (int w = 0; w < width; w++)
{
value = fits.PixelMap[w + h * width];
/* Min - max scaling --------------------------------*/
temp = (value - z1) * scale;
if (temp > 255.0)
{
byteValue = 255;
}
else
{
byteValue = (byte)temp;
}
/* _________________________________________________ */
newColor = Color.FromArgb(byteValue, byteValue, byteValue);
fits.Bitmap.SetPixel(width - w - 1, height - h - 1, newColor);
}
}
fits.Scaled = true;
}
