/// <summary>
/// Create a rotation matrix for rotating an image
/// </summary>
/// <param name="angle">The rotation angle in degrees. Positive values mean couter-clockwise rotation (the coordiate origin is assumed at image centre). </param>
/// <param name="center">The rotation center</param>
/// <param name="srcImageSize">The source image size</param>
/// <param name="dstImageSize">The minimun size of the destination image</param>
/// <returns>The rotation matrix that rotate the source image to the destination image.</returns>
public static RotationMatrix2D CreateRotationMatrix(PointF center, double angle, Size srcImageSize, out Size dstImageSize)
{
RotationMatrix2D rotationMatrix = new RotationMatrix2D(center, angle, 1);
PointF[] corners = new PointF[] {
new PointF(0, 0),
new PointF(srcImageSize.Width - 1, 0),
new PointF(srcImageSize.Width - 1, srcImageSize.Height - 1),
new PointF(0, srcImageSize.Height - 1)
};
rotationMatrix.RotatePoints(corners);
int minX = (int)Math.Round(Math.Min(Math.Min(corners[0].X, corners[1].X), Math.Min(corners[2].X, corners[3].X)));
int maxX = (int)Math.Round(Math.Max(Math.Max(corners[0].X, corners[1].X), Math.Max(corners[2].X, corners[3].X)));
int minY = (int)Math.Round(Math.Min(Math.Min(corners[0].Y, corners[1].Y), Math.Min(corners[2].Y, corners[3].Y)));
int maxY = (int)Math.Round(Math.Max(Math.Max(corners[0].Y, corners[1].Y), Math.Max(corners[2].Y, corners[3].Y)));
using (Matrix <double> offset = new Matrix <double>(2, 3))
{
offset[0, 2] = minX;
offset[1, 2] = minY;
CvInvoke.Subtract(rotationMatrix, offset, rotationMatrix);
//rotationMatrix[0, 2] -= minX;
//rotationMatrix[1, 2] -= minY;
}
dstImageSize = new Size(maxX - minX + 1, maxY - minY + 1);
return(rotationMatrix);
}
/// <summary>
/// Generate a random point cloud around the ellipse.
/// </summary>
/// <param name="e">The region where the point cloud will be generated. The axes of e corresponds to std of the random point cloud.</param>
/// <param name="numberOfPoints">The number of points to be generated</param>
/// <returns>A random point cloud around the ellipse</returns>
public static PointF[] GeneratePointCloud(Ellipse e, int numberOfPoints)
{
PointF[] cloud = new PointF[numberOfPoints];
GCHandle handle = GCHandle.Alloc(cloud, GCHandleType.Pinned);
using (Matrix <float> points = new Matrix <float>(numberOfPoints, 2, handle.AddrOfPinnedObject()))
using (Matrix <float> xValues = points.GetCol(0))
using (Matrix <float> yValues = points.GetCol(1))
using (RotationMatrix2D <float> rotation = new RotationMatrix2D <float>(e.MCvBox2D.center, e.MCvBox2D.angle, 1.0))
{
xValues.SetRandNormal(new MCvScalar(e.MCvBox2D.center.X), new MCvScalar(e.MCvBox2D.size.Width / 2.0f));
yValues.SetRandNormal(new MCvScalar(e.MCvBox2D.center.Y), new MCvScalar(e.MCvBox2D.size.Height / 2.0f));
rotation.RotatePoints(points);
}
handle.Free();
return(cloud);
}
/*
/// <summary>
/// Re-project pixels on a 1-channel disparity map to array of 3D points.
/// </summary>
/// <param name="disparity">Disparity map</param>
/// <param name="Q">The re-projection 4x4 matrix, can be arbitrary, e.g. the one, computed by cvStereoRectify</param>
/// <returns>The reprojected 3D points</returns>
public static MCvPoint3D32f[] ReprojectImageTo3D(Image<Gray, Byte> disparity, Matrix<double> Q)
{
Size size = disparity.Size;
MCvPoint3D32f[] points3D = new MCvPoint3D32f[size.Width * size.Height];
GCHandle handle = GCHandle.Alloc(points3D, GCHandleType.Pinned);
using (Matrix<float> pts = new Matrix<float>(size.Height, size.Width, 3, handle.AddrOfPinnedObject(), 0))
CvInvoke.ReprojectImageTo3D(disparity, pts, Q, false, CvEnum.DepthType.Cv32F);
handle.Free();
return points3D;
}*/
/// <summary>
/// Generate a random point cloud around the ellipse.
/// </summary>
/// <param name="e">The region where the point cloud will be generated. The axes of e corresponds to std of the random point cloud.</param>
/// <param name="numberOfPoints">The number of points to be generated</param>
/// <returns>A random point cloud around the ellipse</returns>
public static PointF[] GeneratePointCloud(Ellipse e, int numberOfPoints)
{
PointF[] cloud = new PointF[numberOfPoints];
GCHandle handle = GCHandle.Alloc(cloud, GCHandleType.Pinned);
using (Matrix<float> points = new Matrix<float>(numberOfPoints, 2, handle.AddrOfPinnedObject()))
using (Matrix<float> xValues = points.GetCol(0))
using (Matrix<float> yValues = points.GetCol(1))
using (RotationMatrix2D rotation = new RotationMatrix2D(e.RotatedRect.Center, e.RotatedRect.Angle, 1.0))
using (Mat tmp = new Mat())
{
rotation.ConvertTo(tmp, DepthType.Cv32F);
xValues.SetRandNormal(new MCvScalar(e.RotatedRect.Center.X), new MCvScalar(e.RotatedRect.Size.Width / 2.0f));
yValues.SetRandNormal(new MCvScalar(e.RotatedRect.Center.Y), new MCvScalar(e.RotatedRect.Size.Height / 2.0f));
rotation.RotatePoints(points);
}
handle.Free();
return cloud;
}
/// <summary>
/// Create a rotation matrix for rotating an image
/// </summary>
/// <param name="angle">The rotation angle in degrees. Positive values mean couter-clockwise rotation (the coordiate origin is assumed at image centre). </param>
/// <param name="center">The rotation center</param>
/// <param name="srcImageSize">The source image size</param>
/// <param name="dstImageSize">The minimun size of the destination image</param>
/// <returns>The rotation matrix that rotate the source image to the destination image.</returns>
public static RotationMatrix2D <float> CreateRotationMatrix(PointF center, double angle, Size srcImageSize, out Size dstImageSize)
{
RotationMatrix2D <float> rotationMatrix = new RotationMatrix2D <float>(center, angle, 1);
PointF[] corners = new PointF[] {
new PointF(0, 0),
new PointF(srcImageSize.Width - 1, 0),
new PointF(srcImageSize.Width - 1, srcImageSize.Height - 1),
new PointF(0, srcImageSize.Height - 1)
};
rotationMatrix.RotatePoints(corners);
int minX = (int)Math.Round(Math.Min(Math.Min(corners[0].X, corners[1].X), Math.Min(corners[2].X, corners[3].X)));
int maxX = (int)Math.Round(Math.Max(Math.Max(corners[0].X, corners[1].X), Math.Max(corners[2].X, corners[3].X)));
int minY = (int)Math.Round(Math.Min(Math.Min(corners[0].Y, corners[1].Y), Math.Min(corners[2].Y, corners[3].Y)));
int maxY = (int)Math.Round(Math.Max(Math.Max(corners[0].Y, corners[1].Y), Math.Max(corners[2].Y, corners[3].Y)));
rotationMatrix[0, 2] -= minX;
rotationMatrix[1, 2] -= minY;
dstImageSize = new Size(maxX - minX + 1, maxY - minY + 1);
return(rotationMatrix);
}