// http://www.w3.org/TR/AERT#color-contrast
/// <summary>
/// Sort RGB pixels by luminance (0.299 Red 0.587 Green 0.114 Blue)
/// </summary>
/// <param name="image">image OpenCv matrix</param>
/// <returns>Sorted list</returns>
private static List <Point3D> SortPixelsByLuminance(Mat image)
{
var image_indexer = GetByteVectorIndexer(image);
//convert RGB to Point3D
var rgb_points = new Point3DCollection();
for (int i = 0; i < image.Width; i++)
{
for (int j = 0; j < image.Height; j++)
{
var rgb1 = image_indexer[i, j];
rgb_points.Add(new Point3D((double)rgb1.Item2, (double)rgb1.Item1, (double)rgb1.Item0));
}
}
// Sort RGB pixels by luminance 0.299 Red 0.587 Green 0.114 Blue
// http://www.w3.org/TR/AERT#color-contrast
var rgb_sorted_list = rgb_points.OrderBy(p => 0.299 * p.X + 0.587 * p.Y + 0.114 * p.Z).ToList();
return(rgb_sorted_list);
}
private void GenerateTextureCordinatesFromPos()
{
var templist = _Positions.OrderBy(x => x.X).ToList();
double minx = templist[0].X, maxx = templist[templist.Count - 1].X;
templist = _Positions.OrderBy(y => y.Y).ToList();
double miny = templist[0].Y, maxy = templist[templist.Count - 1].Y;
templist = _Positions.OrderBy(z => z.Z).ToList();
double _minz = templist[0].Z, _maxz = templist[templist.Count - 1].Z;
double zrange = _maxz - _minz;
double zmean = (_minz + _minz) / 2;
double xrange = maxx - minx;
double yrange = maxy - miny;
double xyratio = (double)1920 / 1080;
//keep the face width to 18% of the texture image
double xratio = 0.18 / xrange;
double yratio = xratio * xyratio;
//offset to center of texture image
double offsetx = 0.5 - ((minx + maxx) / 2) * xratio;
double offsety = 0.5 + ((miny + maxy) / 2) * yratio;
_TextureCoordinates = new PointCollection();
//double MAX_MULTIPLIER_X = 0.055;
//double MAX_MULTIPLIER_Y = 0.055;
double CAM_Z_POS = 0.5;
foreach (var newpoint in _Positions)
{
//the nearer to the camera, the greater the multiplier
////X multiplier
//double zdeltaX = MAX_MULTIPLIER_X * (((newpoint.Z - _minz)) / (zrange));
//double zratioX = 1 + zdeltaX;//1 + zdeltaX;
////Y multiplier
//double zdeltaY = MAX_MULTIPLIER_Y * (((newpoint.Z - _minz)) / (zrange));
//double zratioY = 1 + zdeltaY;//1 + zdeltaY;
//Another way of looking at this..
// double magnifier = (CAM_Z_POS - _minz) / (CAM_Z_POS - newpoint.Z);
// double magnifier = (0.5-MEAN_X_FROM_CAM) / (CAM_Z_POS - newpoint.Z -MEAN_X_FROM_CAM);
double magnifierX = (CAM_Z_POS + 0.1) / (CAM_Z_POS - newpoint.Z);
double magnifierY = (CAM_Z_POS + 0.1) / (CAM_Z_POS - newpoint.Z);
double zratioX = magnifierX;
double zratioY = magnifierY;
double x = zratioX * newpoint.X * xratio + offsetx;
//Y direction in World Coordinates is reverse of Texture Coordinate
double y = -newpoint.Y * yratio * zratioY + offsety;
_TextureCoordinates.Add(new Point(x, y));
}
}