/// <summary>
/// Computes the center moments for the specified image.
/// </summary>
///
/// <param name="image">The image whose moments should be computed.</param>
/// <param name="area">The region of interest in the image to compute moments for.</param>
///
public override void Compute(float[,] image, Rectangle area)
{
RawMoments raw = new RawMoments(image, area, Order);
CentralMoments center = new CentralMoments(raw);
this.Compute(center);
}
/// <summary>
/// Computes the center moments for the specified image.
/// </summary>
///
/// <param name="image">The image.</param>
/// <param name="area">The region of interest in the image to compute moments for.</param>
///
public unsafe void Compute(float[,] image, Rectangle area)
{
RawMoments raw = new RawMoments();
raw.Compute(image, area, true);
this.Compute(raw);
}
/// <summary>
/// Computes the center moments for the specified image.
/// </summary>
///
/// <param name="image">The image.</param>
/// <param name="area">The region of interest in the image to compute moments for.</param>
///
public unsafe void Compute(UnmanagedImage image, Rectangle area)
{
RawMoments raw = new RawMoments();
raw.Compute(image, area, true);
this.Compute(raw);
}
public void RawMomentsConstructorTest2()
{
var hu = Accord.Imaging.Image.Clone(Resources.hu);
float[,] image;
new ImageToMatrix()
{
Min = 0,
Max = 255
}.Convert(hu, out image);
RawMoments target = new RawMoments(image, order: 3);
Assert.AreEqual(86424.0 / target.M00, 1);
Assert.AreEqual(1.177254E+7 / target.M01, 1, 1e-10);
Assert.AreEqual(2.19032653E+9 / target.M02, 1, 1e-8);
Assert.AreEqual(1.5264756E7 / target.M10, 1, 1e-10);
Assert.AreEqual(2.08566813E9 / target.M11, 1, 1e-6);
Assert.AreEqual(3.8643911413E11 / target.M12, 1, 1e-5);
Assert.AreEqual(3.604560164E9 / target.M20, 1, 1e-3);
Assert.AreEqual(4.9401212329E11 / target.M21, 1, 1e-3);
Assert.AreEqual(9.451364E+11 / target.M30, 1, 1e-8);
Assert.AreEqual(4.599169E+11 / target.M03, 1, 1e-8);
}
/// <summary>
/// Computes the center moments from the specified raw moments.
/// </summary>
///
/// <param name="moments">The raw moments to use as base of calculations.</param>
///
public void Compute(RawMoments moments)
{
Mu00 = moments.M00;
Mu01 = Mu10 = 0;
Mu20 = moments.M20 - moments.M10 * moments.CenterX;
Mu02 = moments.M02 - moments.M01 * moments.CenterY;
Mu11 = moments.M11 - moments.M01 * moments.CenterX;
invM00 = moments.InvM00;
}
public void RawMomentsConstructorTest()
{
Bitmap image = Resources.hu;
RawMoments target = new RawMoments(image, order: 3);
Assert.AreEqual(86424.0 / target.M00, 1);
Assert.AreEqual(1.177254E+7 / target.M01, 1, 1e-10);
Assert.AreEqual(2.19032653E+9 / target.M02, 1, 1e-8);
Assert.AreEqual(1.5264756E7 / target.M10, 1, 1e-10);
Assert.AreEqual(2.08566813E9 / target.M11, 1, 1e-6);
Assert.AreEqual(3.8643911413E11 / target.M12, 1, 1e-5);
Assert.AreEqual(3.604560164E9 / target.M20, 1, 1e-3);
Assert.AreEqual(4.9401212329E11 / target.M21, 1, 1e-3);
Assert.AreEqual(9.451364E+11 / target.M30, 1, 1e-8);
Assert.AreEqual(4.599169E+11 / target.M03, 1, 1e-8);
}
/// <summary>
/// Computes the center moments from the specified raw moments.
/// </summary>
///
/// <param name="moments">The raw moments to use as base of calculations.</param>
///
public void Compute(RawMoments moments)
{
float x = moments.CenterX;
float y = moments.CenterY;
Mu00 = moments.M00;
Mu01 = Mu10 = 0;
Mu11 = moments.M11 - moments.M01 * x;
Mu20 = moments.M20 - moments.M10 * x;
Mu02 = moments.M02 - moments.M01 * y;
Mu21 = moments.M21 - 2 * x * moments.M11 - y * moments.M20 + 2 * x * x * moments.M01;
Mu12 = moments.M12 - 2 * y * moments.M11 - x * moments.M02 + 2 * y * y * moments.M10;
Mu30 = moments.M30 - 3 * x * moments.M20 + 2 * x * x * moments.M10;
Mu03 = moments.M03 - 3 * y * moments.M02 + 2 * y * y * moments.M01;
invM00 = moments.InvM00;
}
/// <summary>
/// Computes the center moments for the specified image.
/// </summary>
///
/// <param name="image">The image.</param>
/// <param name="area">The region of interest in the image to compute moments for.</param>
///
public unsafe void Compute(float[,] image, Rectangle area)
{
RawMoments raw = new RawMoments();
raw.Compute(image, area, true);
this.Compute(raw);
}
/// <summary>
/// Computes the center moments from the specified raw moments.
/// </summary>
///
/// <param name="moments">The raw moments to use as base of calculations.</param>
///
public void Compute(RawMoments moments)
{
Mu00 = moments.M00;
Mu01 = Mu10 = 0;
Mu20 = moments.M20 - moments.M10 * moments.CenterX;
Mu02 = moments.M02 - moments.M01 * moments.CenterY;
Mu11 = moments.M11 - moments.M01 * moments.CenterX;
invM00 = moments.InvM00;
}
/// <summary>
/// Mean shift algorithm
/// </summary>
///
private CentralMoments meanShift(UnmanagedImage frame)
{
// Variable initialization
int width = frame.Width;
int height = frame.Height;
// (assume all frames have equal dimensions)
if (map == null) map = new float[height, width];
// Grab the current region of interest in the current frame
Rectangle roi = conservative ? searchWindow : new Rectangle(0, 0, frame.Width, frame.Height);
// Compute the histogram for the current frame
float[] currentHistogram = createHistogram(frame, roi);
// Use the previous histogram to compute a ratio histogram (storing in current)
computeHistogramRatio(originalHistogram, currentHistogram, currentHistogram);
// Compute the back-projection map using the ratio histogram
lock (sync) generateBackprojectionMap(frame, currentHistogram);
RawMoments moments = new RawMoments(1);
// Mean shift with fixed number of iterations
for (int i = 0; i < MAX_ITERATIONS - 1; i++)
{
// Locate first order moments
moments.Compute(map, searchWindow);
// Shift the mean (centroid)
searchWindow.X += (int)(moments.CenterX - searchWindow.Width / 2f);
searchWindow.Y += (int)(moments.CenterY - searchWindow.Height / 2f);
}
// Locate second order moments and perform final shift
moments.Order = 2; moments.Compute(map, searchWindow);
searchWindow.X += (int)(moments.CenterX - searchWindow.Width / 2f);
searchWindow.Y += (int)(moments.CenterY - searchWindow.Height / 2f);
// Keep the search window inside the image
searchWindow.X = Math.Max(0, Math.Min(searchWindow.X, width));
searchWindow.Y = Math.Max(0, Math.Min(searchWindow.Y, height));
return new CentralMoments(moments); // moments to be used by Camshift
}
/// <summary>
/// Computes the center moments from the specified raw moments.
/// </summary>
///
/// <param name="moments">The raw moments to use as base of calculations.</param>
///
public void Compute(RawMoments moments)
{
float x = moments.CenterX;
float y = moments.CenterY;
Mu00 = moments.M00;
Mu01 = Mu10 = 0;
Mu11 = moments.M11 - moments.M01 * x;
Mu20 = moments.M20 - moments.M10 * x;
Mu02 = moments.M02 - moments.M01 * y;
Mu21 = moments.M21 - 2 * x * moments.M11 - y * moments.M20 + 2 * x * x * moments.M01;
Mu12 = moments.M12 - 2 * y * moments.M11 - x * moments.M02 + 2 * y * y * moments.M10;
Mu30 = moments.M30 - 3 * x * moments.M20 + 2 * x * x * moments.M10;
Mu03 = moments.M03 - 3 * y * moments.M02 + 2 * y * y * moments.M01;
invM00 = moments.InvM00;
}
/// <summary>
/// Initializes a new instance of the <see cref="CentralMoments"/> class.
/// </summary>
///
/// <param name="moments">The raw moments to construct central moments.</param>
///
public CentralMoments(RawMoments moments)
: base(moments.Order)
{
Compute(moments);
}
/// <summary>
/// Computes the center moments for the specified image.
/// </summary>
///
/// <param name="image">The image whose moments should be computed.</param>
/// <param name="area">The region of interest in the image to compute moments for.</param>
///
public override void Compute(float[,] image, Rectangle area)
{
RawMoments raw = new RawMoments(image, area, Order);
CentralMoments center = new CentralMoments(raw);
this.Compute(center);
}
public void RawMomentsConstructorTest3()
{
float[,] img =
{
{ 1, 2, 3, 4, 5 },
{ 6, 7, 8, 9, 10 },
{ 11, 12, 13, 14, 15 },
{ 16, 17, 18, 19, 20 },
};
double sum = img.Sum().Sum();
RawMoments raw = new RawMoments(img);
Assert.AreEqual(sum, raw.M00);
}
/// <summary>
/// Initializes a new instance of the <see cref="CentralMoments"/> class.
/// </summary>
///
/// <param name="moments">The raw moments to construct central moments.</param>
///
public CentralMoments(RawMoments moments)
: base(moments.Order)
{
Compute(moments);
}
/// <summary>
/// Computes the center moments for the specified image.
/// </summary>
///
/// <param name="image">The image.</param>
/// <param name="area">The region of interest in the image to compute moments for.</param>
///
public unsafe void Compute(UnmanagedImage image, Rectangle area)
{
RawMoments raw = new RawMoments();
raw.Compute(image, area, true);
this.Compute(raw);
}
/// <summary>
/// Initializes a new instance of the <see cref="CentralMoments"/> class.
/// </summary>
///
/// <param name="moments">The raw moments to construct central moments.</param>
///
public CentralMoments(RawMoments moments)
{
Compute(moments);
}
/// <summary>
/// Initializes a new instance of the <see cref="CentralMoments"/> class.
/// </summary>
///
/// <param name="moments">The raw moments to construct central moments.</param>
///
public CentralMoments(RawMoments moments)
{
Compute(moments);
}
