private static CoordinateSystemGrid FindForLineCalibration(CalibrationHelper calibrationHelper)
{
CoordinateSystemGrid grid = new CoordinateSystemGrid();
RectangleF imageBounds = new RectangleF(PointF.Empty, calibrationHelper.ImageSize);
// The clip window is an inflated version of the image to account for distortion.
RectangleF clipWindow = imageBounds.CenteredScale(1.3f);
// Create a fake plane to act as the user-defined projected plane.
QuadrilateralF quadImage = new QuadrilateralF(imageBounds.Deflate(2.0f));
PointF a = calibrationHelper.GetPointFromRectified(quadImage.A);
PointF b = calibrationHelper.GetPointFromRectified(quadImage.B);
PointF d = calibrationHelper.GetPointFromRectified(quadImage.D);
RectangleF plane = new RectangleF(0, 0, b.X - a.X, a.Y - d.Y);
// Define the extended plane (for vanishing point replacement and drawing stop condition) as the reprojection of the whole image.
QuadrilateralF extendedPlane = ReprojectImageBounds(calibrationHelper, new QuadrilateralF(imageBounds));
CalibrationPlane calibrator = new CalibrationPlane();
calibrator.Initialize(plane.Size, quadImage);
PointF originImage = calibrationHelper.GetOrigin();
PointF originRectified = originImage;
if (calibrationHelper.DistortionHelper != null && calibrationHelper.DistortionHelper.Initialized)
{
originRectified = calibrationHelper.DistortionHelper.Undistort(originImage);
}
calibrator.SetOrigin(originRectified);
// From this point on we are mostly in the same situation as for plane calibration.
// stepping size is the same in both directions.
int targetSteps = 15;
float width = extendedPlane.B.X - extendedPlane.A.X;
float step = RangeHelper.FindUsableStepSize(width, targetSteps);
CreateVerticalGridLines(grid, 0, -step, calibrator, clipWindow, plane, extendedPlane, true, false, PointF.Empty);
CreateVerticalGridLines(grid, step, step, calibrator, clipWindow, plane, extendedPlane, true, false, PointF.Empty);
CreateHorizontalGridLines(grid, 0, -step, calibrator, clipWindow, plane, extendedPlane, true, false, PointF.Empty);
CreateHorizontalGridLines(grid, step, step, calibrator, clipWindow, plane, extendedPlane, true, false, PointF.Empty);
return(grid);
}
private static QuadrilateralF ReprojectImageBounds(CalibrationHelper calibrationHelper, QuadrilateralF quadImage)
{
// Project image bounds from image space to plane space, using the line calibration setup.
// This can be used to define safe boundaries.
// The method cannot be used with plane calibration as image points can be above the vanishing line. (reproject behind the camera).
// The quad passed in is assumed to be a rectangle.
if (calibrationHelper.CalibratorType != CalibratorType.Line)
{
throw new ArgumentException("Unsupported operation.");
}
PointF a = calibrationHelper.GetPointFromRectified(quadImage.A);
PointF b = calibrationHelper.GetPointFromRectified(quadImage.B);
PointF c = calibrationHelper.GetPointFromRectified(quadImage.C);
PointF d = calibrationHelper.GetPointFromRectified(quadImage.D);
QuadrilateralF plane = new QuadrilateralF(a, b, c, d);
return(plane);
}
private void CreateScatterPlot()
{
PlotModel model = new PlotModel();
model.PlotType = PlotType.Cartesian;
model.Title = this.tbTitle.Text;
double padding = 0.1;
LinearAxis xAxis = new LinearAxis();
xAxis.MajorGridlineColor = OxyColor.FromArgb(40, 0, 0, 139);
xAxis.MajorGridlineStyle = LineStyle.Solid;
xAxis.MinorGridlineColor = OxyColor.FromArgb(20, 0, 0, 139);
xAxis.MinorGridlineStyle = LineStyle.Solid;
xAxis.Position = AxisPosition.Bottom;
xAxis.MinimumPadding = 0.1;
xAxis.MaximumPadding = 0.1;
xAxis.Title = tbXAxis.Text;
model.Axes.Add(xAxis);
LinearAxis yAxis = new LinearAxis();
yAxis.MajorGridlineColor = OxyColor.FromArgb(40, 0, 0, 139);
yAxis.MajorGridlineStyle = LineStyle.Solid;
yAxis.MinorGridlineColor = OxyColor.FromArgb(20, 0, 0, 139);
yAxis.MinorGridlineStyle = LineStyle.Solid;
yAxis.MinimumPadding = 0.1;
yAxis.MaximumPadding = 0.1;
yAxis.Title = tbYAxis.Text;
model.Axes.Add(yAxis);
ScatterSeries series = new ScatterSeries();
series.MarkerType = MarkerType.Plus;
series.MarkerStroke = OxyColors.Black;
float yDataMinimum = float.MaxValue;
float yDataMaximum = float.MinValue;
float xDataMinimum = float.MaxValue;
float xDataMaximum = float.MinValue;
foreach (TimedPoint point in points)
{
PointF p = metadata.CalibrationHelper.GetPointAtTime(point.Point, point.T);
series.Points.Add(new ScatterPoint(p.X, p.Y));
yDataMinimum = Math.Min(yDataMinimum, p.Y);
yDataMaximum = Math.Max(yDataMaximum, p.Y);
xDataMinimum = Math.Min(xDataMinimum, p.X);
xDataMaximum = Math.Min(xDataMaximum, p.X);
}
model.Series.Add(series);
if (metadata.CalibrationHelper.CalibratorType == CalibratorType.Plane)
{
cbCalibrationPlane.Checked = true;
cbCalibrationPlane.Enabled = true;
CalibrationHelper calibrator = metadata.CalibrationHelper;
QuadrilateralF quadImage = calibrator.CalibrationByPlane_GetProjectedQuad();
PointF a = calibrator.GetPointFromRectified(quadImage.A);
PointF b = calibrator.GetPointFromRectified(quadImage.B);
PointF c = calibrator.GetPointFromRectified(quadImage.C);
PointF d = calibrator.GetPointFromRectified(quadImage.D);
rectangleAnnotation = new RectangleAnnotation();
rectangleAnnotation.MinimumX = a.X;
rectangleAnnotation.MaximumX = b.X;
rectangleAnnotation.MinimumY = d.Y;
rectangleAnnotation.MaximumY = a.Y;
rectangleAnnotation.Fill = OxyColor.FromArgb(96, 173, 223, 247);
rectangleAnnotation.Layer = AnnotationLayer.BelowAxes;
model.Annotations.Add(rectangleAnnotation);
if (a.Y > yDataMaximum || d.Y < yDataMinimum)
{
yDataMaximum = Math.Max(yDataMaximum, a.Y);
yDataMinimum = Math.Min(yDataMinimum, d.Y);
double yPadding = (yDataMaximum - yDataMinimum) * padding;
yAxis.Maximum = yDataMaximum + yPadding;
yAxis.Minimum = yDataMinimum - yPadding;
}
if (b.X > xDataMaximum || a.X < xDataMinimum)
{
xDataMaximum = Math.Max(xDataMaximum, b.X);
xDataMinimum = Math.Min(xDataMinimum, a.X);
double xPadding = (xDataMaximum - xDataMinimum) * padding;
xAxis.Maximum = xDataMaximum + xPadding;
xAxis.Minimum = xDataMinimum - xPadding;
}
}
else
{
cbCalibrationPlane.Checked = false;
cbCalibrationPlane.Enabled = false;
}
plotScatter.Model = model;
}
private static CoordinateSystemGrid FindForPlaneCalibration(CalibrationHelper calibrationHelper)
{
CoordinateSystemGrid grid = new CoordinateSystemGrid();
RectangleF imageBounds = new RectangleF(PointF.Empty, calibrationHelper.ImageSize);
RectangleF clipWindow = imageBounds;
CalibrationPlane calibrator = calibrationHelper.CalibrationByPlane_GetCalibrator();
RectangleF plane = new RectangleF(PointF.Empty, calibrator.Size);
int targetSteps = 15;
float stepVertical = 1.0f;
float stepHorizontal = 1.0f;
// The extended plane is used for vanishing point replacement and iteration stop condition.
QuadrilateralF extendedPlane;
bool orthogonal;
if (!calibrator.QuadImage.IsRectangle)
{
// If perspective plane, define as 2n times the nominal plane centered on origin.
orthogonal = false;
float n = 4;
PointF a = new PointF(-calibrator.Size.Width * n, calibrator.Size.Height * n);
PointF b = new PointF(calibrator.Size.Width * n, calibrator.Size.Height * n);
PointF c = new PointF(calibrator.Size.Width * n, -calibrator.Size.Height * n);
PointF d = new PointF(-calibrator.Size.Width * n, -calibrator.Size.Height * n);
extendedPlane = new QuadrilateralF(a, b, c, d);
QuadrilateralF quadImage = calibrator.QuadImage;
float projectedWidthLength = GeometryHelper.GetDistance(quadImage.A, quadImage.B);
float scaledTargetHorizontal = targetSteps / (calibrationHelper.ImageSize.Width / projectedWidthLength);
stepHorizontal = RangeHelper.FindUsableStepSize(plane.Width, scaledTargetHorizontal);
float projectedHeightLength = GeometryHelper.GetDistance(quadImage.A, quadImage.D);
float scaledTargetVertical = targetSteps / (calibrationHelper.ImageSize.Height / projectedHeightLength);
stepVertical = RangeHelper.FindUsableStepSize(plane.Height, scaledTargetVertical);
}
else
{
// If flat plane (and no distortion) we know there is no way to get any vanishing point inside the image,
// so we can safely use the whole image reprojection as an extended plane.
orthogonal = true;
QuadrilateralF quadImageBounds = new QuadrilateralF(imageBounds);
PointF a = calibrationHelper.GetPointFromRectified(quadImageBounds.A);
PointF b = calibrationHelper.GetPointFromRectified(quadImageBounds.B);
PointF c = calibrationHelper.GetPointFromRectified(quadImageBounds.C);
PointF d = calibrationHelper.GetPointFromRectified(quadImageBounds.D);
extendedPlane = new QuadrilateralF(a, b, c, d);
float width = extendedPlane.B.X - extendedPlane.A.X;
stepHorizontal = RangeHelper.FindUsableStepSize(width, targetSteps);
float height = extendedPlane.A.Y - extendedPlane.D.Y;
stepVertical = RangeHelper.FindUsableStepSize(height, targetSteps);
}
//-------------------------------------------------------------------------------------------------
// There is a complication with points behind the camera, as they projects above the vanishing line.
// The general strategy is the following:
// Find out if the vanishing point is inside the image. Reminder: parallel lines share the same vanishing point.
// If it is not inside the image, there is no risk, so we take two points on the line and draw an infinite line that we clip against the image bounds.
// If it is inside the image:
// Take two points on the line and project them in image space. They are colinear with the vanishing point in image space.
// Find on which side of the quadrilateral the vanishing point is.
// If the vanishing point is above the quad, draw a ray from the top of the extended quad, down to infinity.
// If the vanishing point is below the quad, draw a ray from the bottom of the extended quad, up to infinity.
//
// Stepping strategy:
// We start at origin and progress horizontally and vertically until we find a gridline that is completely clipped out.
//-------------------------------------------------------------------------------------------------
// Vertical lines.
PointF yVanish = new PointF(0, float.MinValue);
bool yVanishVisible = false;
Vector3 yv = calibrator.Project(new Vector3(0, 1, 0));
if (yv.Z != 0)
{
yVanish = new PointF(yv.X / yv.Z, yv.Y / yv.Z);
yVanishVisible = clipWindow.Contains(yVanish);
}
CreateVerticalGridLines(grid, 0, -stepHorizontal, calibrator, clipWindow, plane, extendedPlane, orthogonal, yVanishVisible, yVanish);
CreateVerticalGridLines(grid, stepHorizontal, stepHorizontal, calibrator, clipWindow, plane, extendedPlane, orthogonal, yVanishVisible, yVanish);
// Horizontal lines
PointF xVanish = new PointF(float.MinValue, 0);
bool xVanishVisible = false;
Vector3 xv = calibrator.Project(new Vector3(1, 0, 0));
if (xv.Z != 0)
{
xVanish = new PointF(xv.X / xv.Z, xv.Y / xv.Z);
xVanishVisible = clipWindow.Contains(xVanish);
}
CreateHorizontalGridLines(grid, 0, -stepVertical, calibrator, clipWindow, plane, extendedPlane, orthogonal, xVanishVisible, xVanish);
CreateHorizontalGridLines(grid, stepVertical, stepVertical, calibrator, clipWindow, plane, extendedPlane, orthogonal, xVanishVisible, xVanish);
return(grid);
}
