/// <summary>
/// Flip/Rotate Filter constructor
/// </summary>
public FlipRotateFilter()
{
_innerFilter = new SpatialTransformFilter();
FilterParameter flipVertical = new FilterParameter(FLIPVERTICAL, "Verical flip of the image", (bool)false);
FilterParameter flipHorizontal = new FilterParameter(FLIPHORIZONTAL, "Horizontal Flip of the image", (bool)false);
FilterParameter rotation = new FilterParameter(ROTATION, "Rotate the image", (RotationValue)RotationValue.NoRotation);
AddParameter(flipVertical);
AddParameter(flipHorizontal);
AddParameter(rotation);
}
/// <summary>
/// Filter Implementation
/// </summary>
protected override IImageAdapter ProcessFilter(IImageAdapter source)
{
IImageAdapter retVal = null;
if (source == null)
{
throw new ArgumentNullException("source", "IImageAdapter must be set to a valid instance (null passed in)");
}
if (MorphToShape != Shape.Square && MorphToShape != Shape.Circle)
{
throw new NotImplementedException("Will be implemented if requested");
}
int width = source.Width;
int height = source.Height;
int side = 0;
if (ExtendToMaxSide == false)
{
side = (int)Math.Min(width, height);
}
else
{
side = (int)Math.Max(width, height);
}
retVal = new ImageAdapter(side, side);
if (MorphToShape == Shape.Square || MorphToShape == Shape.Circle)
{
// Shrink/Expand image to square
double ratio = (double)width / (double)height;
double[] matrix = new double[] { 1, 0, 0, 1, 0, 0 };
if (ratio >= 1.0)
{
if (ExtendToMaxSide)
{
matrix[3] *= ratio;
}
else
{
matrix[0] /= ratio;
}
}
else
{
if (ExtendToMaxSide)
{
matrix[0] /= ratio;
}
else
{
matrix[3] *= ratio;
}
}
SpatialTransformFilter filter = new SpatialTransformFilter();
filter.Matrix = matrix;
retVal = filter.Process(source);
}
// Step 2 : Compute every pixel in resulting image
if (MorphToShape == Shape.Circle)
{
int x = 0;
int y = 0;
double center = side / 2.0;
double Y = double.NaN;
double X = double.NaN;
double theta = double.NaN;
double ratio = double.NaN;
double xSource = double.NaN;
double ySource = double.NaN;
ImageAdapter temp = new ImageAdapter(side, side);
for (y = 0; y < side; y++)
{
for (x = 0; x < side; x++)
{
X = x - center;
Y = center - y;
theta = Math.Atan(Y / X);
ratio = Math.Max(Math.Abs(Math.Cos(theta)), Math.Abs(Math.Sin(theta)));
xSource = X / ratio + center;
ySource = -(Y / ratio - center);
if (xSource >= 0 && xSource < side && ySource >= 0 && ySource < side)
{
temp[x, y] = (IColor)retVal[(int)xSource, (int)ySource].Clone();
}
else
{
temp[x, y] = (IColor)retVal[0, 0].Clone(); temp[x, y].IsEmpty = true;
}
}
}
retVal = temp;
}
return(retVal);
}
