private void initTracking(Bgr<byte>[,] frame)
{
initializeKalman(roi.Center());
//get hue channel from search area
var hsvImg = frame.ToHsv();
//user constraints...
Gray<byte>[,] mask = hsvImg.InRange(new Hsv<byte>(0, 0, (byte)minV), new Hsv<byte>(0, 0, (byte)maxV), Byte.MaxValue, 2);
originalObjHist.Calculate(hsvImg.SplitChannels<Hsv<byte>, byte>(roi, 0, 1), false, mask, roi.Location);
originalObjHist.Scale((float)1 / roi.Area());
//originalObjHist.Normalize(Byte.MaxValue);
var backgroundArea = roi.Inflate(1.5, 1.5, frame.Size());
var backgroundMask = mask.Clone(backgroundArea);
backgroundMask.SetValue<Gray<byte>>(0, new Rectangle(roi.X - backgroundArea.X, roi.Y - backgroundArea.Y, roi.Width, roi.Height));
backgroundHist.Calculate(hsvImg.SplitChannels<Hsv<byte>, byte>(backgroundArea, 0, 1), false, mask, backgroundArea.Location);
backgroundHist.Scale((float)1 / (backgroundArea.Area() - roi.Area()));
//backgroundHist.Normalize(Byte.MaxValue);
//how good originalObjHist and objHist match (suppresses possible selected background)
ratioHist = originalObjHist.CreateRatioHistogram(backgroundHist, Byte.MaxValue, 3);
searchArea = roi;
roi = Rectangle.Empty;
}
private void processImage(Bgr<byte>[,] frame, out Gray<byte>[,] probabilityMap, out Rectangle prevSearchArea, out Box2D foundBox)
{
prevSearchArea = searchArea;
//convert to HSV
var hsvImg = frame.ToHsv();
//back-project ratio hist => create probability map
probabilityMap = ratioHist.BackProject(hsvImg.SplitChannels<Hsv<byte>, byte>(0, 1)); //or new Image<Gray<byte>>[]{ hsvImg[0], hsvImg[1]...}
//user constraints...
Gray<byte>[,] mask = hsvImg.InRange(new Hsv<byte>(0, 0, (byte)minV), new Hsv<byte>(0, 0, (byte)maxV), Byte.MaxValue, 2);
probabilityMap.AndByte(mask, inPlace:true);
//run Camshift algorithm to find new object position, size and angle
foundBox = Camshift.Process(probabilityMap, searchArea);
var foundArea = Rectangle.Round(foundBox.GetMinArea());
searchArea = foundArea.Inflate(0.05, 0.05, frame.Size()); //inflate found area for search (X factor)...
if (searchArea.IsEmpty) isROISelected = false; //reset tracking
}
private void processImage(Bgr <byte>[,] frame, out Gray <byte>[,] probabilityMap, out Rectangle prevSearchArea, out Box2D foundBox)
{
prevSearchArea = searchArea;
//convert to HSV
var hsvImg = frame.ToHsv();
//back-project ratio hist => create probability map
probabilityMap = ratioHist.BackProject(hsvImg.SplitChannels <Hsv <byte>, byte>(0, 1)); //or new Image<Gray<byte>>[]{ hsvImg[0], hsvImg[1]...}
//user constraints...
Gray <byte>[,] mask = hsvImg.InRange(new Hsv <byte>(0, 0, (byte)minV), new Hsv <byte>(0, 0, (byte)maxV), Byte.MaxValue, 2);
probabilityMap.AndByte(mask, inPlace: true);
//run Camshift algorithm to find new object position, size and angle
foundBox = Camshift.Process(probabilityMap, searchArea);
var foundArea = Rectangle.Round(foundBox.GetMinArea());
searchArea = foundArea.Inflate(0.05, 0.05, frame.Size()); //inflate found area for search (X factor)...
if (searchArea.IsEmpty)
{
isROISelected = false; //reset tracking
}
}
private void initTracking(Bgr <byte>[,] frame)
{
//get hue channel from search area
var hsvImg = frame.ToHsv();
//user constraints...
Gray <byte>[,] mask = hsvImg.InRange(new Hsv <byte>(0, 0, (byte)minV), new Hsv <byte>(0, 0, (byte)maxV), Byte.MaxValue, 2);
originalObjHist.Calculate(hsvImg.SplitChannels <Hsv <byte>, byte>(roi, 0, 1), !false, mask, roi.Location);
originalObjHist.Scale((float)1 / roi.Area());
//originalObjHist.Normalize(Byte.MaxValue);
var backgroundArea = roi.Inflate(1.5, 1.5, frame.Size());
backgroundHist.Calculate(hsvImg.SplitChannels <Hsv <byte>, byte>(backgroundArea, 0, 1), !false, mask, backgroundArea.Location);
backgroundHist.Scale((float)1 / backgroundArea.Area());
//backgroundHist.Normalize(Byte.MaxValue);
//how good originalObjHist and objHist match (suppresses possible selected background)
ratioHist = originalObjHist.CreateRatioHistogram(backgroundHist, Byte.MaxValue, 10);
searchArea = roi;
roi = Rectangle.Empty;
}
private void trackCamshift(Bgr<byte>[,] frame, Rectangle searchArea, out Gray<byte>[,] probabilityMap, out Box2D foundBox)
{
const int PROBABILITY_MIN_VAL = (int)(0.3f * Byte.MaxValue);
//convert to HSV
var hsvImg = frame.ToHsv();
//back-project ratio hist => create probability map
probabilityMap = ratioHist.BackProject(hsvImg.SplitChannels<Hsv<byte>, byte>(0, 1)); //or new Image<Gray<byte>>[]{ hsvImg[0], hsvImg[1]...}
//user constraints...
Gray<byte>[,] mask = hsvImg.InRange(new Hsv<byte>(0, 0, (byte)minV), new Hsv<byte>(0, 0, (byte)maxV), Byte.MaxValue, 2);
probabilityMap.AndByte(mask, inPlace: true);
//run Camshift algorithm to find new object position, size and angle
CentralMoments centralMoments;
foundBox = Camshift.Process(probabilityMap, searchArea, Meanshift.DEFAULT_TERM, out centralMoments);
//stopping conditions
float avgIntensity = centralMoments.Mu00 / (foundBox.Size.Area() + Single.Epsilon);
if (avgIntensity < PROBABILITY_MIN_VAL || foundBox.Size.IsEmpty || foundBox.Size.Height < 12)
{
foundBox = Box2D.Empty; //invalid box
}
}
