/// <summary>
/// Function for scaling sample data. Used in automatic rotation to reduce calculation time in gradient descent.
/// </summary>
/// <param name="input">Input volume data</param>
/// <param name="scale">Scaling factor, e.g. 0.1 = downsampling with factor of 10.</param>
/// <returns></returns>
public static vtkImageData rescale_sample(vtkImageData input, double scale)
{
//Get sample dimensions
int[] dims = input.GetExtent();
vtkImageResample samplery = vtkImageResample.New();
samplery.SetInput(input);
samplery.SetOutputSpacing(input.GetSpacing()[0], input.GetSpacing()[1], input.GetSpacing()[2]);
samplery.SetOutputOrigin(input.GetOrigin()[0], input.GetOrigin()[1], input.GetOrigin()[2]);
samplery.SetOutputExtent((int)(scale * dims[0]), (int)(scale * dims[1]), dims[2], dims[3], dims[4], dims[5]);
samplery.SetInterpolationModeToCubic();
samplery.SetAxisMagnificationFactor(0, scale);
samplery.Update();
vtkImageResample samplerx = vtkImageResample.New();
samplerx.SetInputConnection(samplery.GetOutputPort());
samplerx.SetOutputSpacing(samplery.GetOutputSpacing()[0], samplery.GetOutputSpacing()[1], samplery.GetOutputSpacing()[2]);
samplerx.SetOutputOrigin(samplery.GetOutputOrigin()[0], samplery.GetOutputOrigin()[1], samplery.GetOutputOrigin()[2]);
samplerx.SetOutputExtent((int)(scale * dims[0]), (int)(scale * dims[1]), (int)(scale * dims[2]), (int)(scale * dims[3]), dims[4], dims[5]);
samplerx.SetInterpolationModeToCubic();
samplerx.SetAxisMagnificationFactor(1, scale);
samplerx.Update();
vtkImageResample samplerz = vtkImageResample.New();
samplerz.SetInputConnection(samplerx.GetOutputPort());
samplerz.SetOutputSpacing(samplerx.GetOutputSpacing()[0], samplerx.GetOutputSpacing()[1], samplerx.GetOutputSpacing()[2]);
samplerz.SetOutputOrigin(samplerx.GetOutputOrigin()[0], samplerx.GetOutputOrigin()[1], samplerx.GetOutputOrigin()[2]);
samplerz.SetOutputExtent((int)(scale * dims[0]), (int)(scale * dims[1]), (int)(scale * dims[2]),
(int)(scale * dims[3]), (int)(scale * dims[4]), (int)(scale * dims[5]));
samplerz.SetInterpolationModeToCubic();
samplerz.SetAxisMagnificationFactor(2, scale);
samplerz.Update();
vtkImageData output = vtkImageData.New();
output.DeepCopy(samplerz.GetOutput());
samplerz.Dispose();
samplerx.Dispose();
samplery.Dispose();
return(output);
}
public static void UpdateSectionImage(Rectangle imageRect)
{
if (SectionImageData == null)
{
SectionImageData = vtkImageData.New();
}
SectionImageData.DeepCopy(RectImageData);
for (int i = 0; i < imageRect.Width; i++)
{
SectionImageData.GetPointData().GetScalars().SetTuple1(HSectionNum * imageRect.Width + i, 255);
}
for (int i = 0; i < imageRect.Height; i++)
{
SectionImageData.GetPointData().GetScalars().SetTuple1(i * imageRect.Width + VSectionNum, 255);
}
SectionImageData.Update();
UpdateImageView();
}
/// <summary>
/// Rotates 3D vtk volume around x and y axes.
/// </summary>
/// <param name="input"></param>
/// <param name="angle"></param>
/// <param name="axis"></param>
/// <param name="out_extent"></param>
/// <returns></returns>
public static vtkImageData rotate_sample(vtkImageData input, double angle, int axis, int out_extent = 0)
{
//get input data dimensions
int[] dims = input.GetExtent();
//Compute centers
int[] centers = new int[] { (dims[1] + dims[0]) / 2, (dims[3] + dims[2]) / 2, (dims[5] + dims[4]) / 2 };
//Set rotation axis
int[] axes = new int[3];
axes[axis] = 1;
int[] new_dims = new int[] { dims[0], dims[1], dims[2], dims[3], dims[4], dims[5] };
int[] new_centers = new int[] { centers[0], centers[1], centers[2] };
//Compute new sample dimensions
if (axis == 0)
{
new_dims[3] = (int)(Math.Cos(Math.Abs(angle / 180) * Math.PI) * new_dims[3] + Math.Sin(Math.Abs(angle / 180) * Math.PI) * new_dims[5]);
new_dims[5] = (int)(Math.Sin(Math.Abs(angle / 180) * Math.PI) * new_dims[3] + Math.Cos(Math.Abs(angle / 180) * Math.PI) * new_dims[5]);
new_centers[1] = (Math.Abs(new_dims[3]) + Math.Abs(new_dims[2])) / 2;
new_centers[2] = (Math.Abs(new_dims[5]) + Math.Abs(new_dims[4])) / 2;
}
if (axis == 1)
{
new_dims[1] = (int)(Math.Cos(Math.Abs(angle / 180) * Math.PI) * new_dims[1] + Math.Sin(Math.Abs(angle / 180) * Math.PI) * new_dims[5]);
new_dims[5] = (int)(Math.Sin(Math.Abs(angle / 180) * Math.PI) * new_dims[1] + Math.Cos(Math.Abs(angle / 180) * Math.PI) * new_dims[5]);
new_centers[0] = (Math.Abs(new_dims[0]) + Math.Abs(new_dims[1])) / 2;
new_centers[2] = (Math.Abs(new_dims[5]) + Math.Abs(new_dims[4])) / 2;
}
//Image transformation
vtkTransform transform = vtkTransform.New();
transform.Translate(centers[0], centers[1], centers[2]);
transform.RotateWXYZ(angle, axes[0], axes[1], axes[2]);
if (out_extent == 0)
{
transform.Translate(-centers[0], -centers[1], -centers[2]);
}
else
{
transform.Translate(-new_centers[0], -new_centers[1], -new_centers[2]);
}
//Console.ReadKey();
transform.Update();
//Compute new data extent
int[] diff = new int[] { new_dims[1] - dims[1], new_dims[3] - dims[3], new_dims[5] - dims[5] };
new_dims[0] += diff[0] / 2; new_dims[1] -= diff[0] / 2;
new_dims[2] += diff[1] / 2; new_dims[3] -= diff[1] / 2;
new_dims[4] += diff[2] / 2; new_dims[5] -= diff[2] / 2;
//Image reslicing
vtkImageReslice rotater = vtkImageReslice.New();
rotater.SetInput(input);
rotater.SetInformationInput(input);
rotater.SetResliceTransform(transform);
rotater.SetInterpolationModeToCubic();
//rotater.SetInterpolationModeToLinear();
if (out_extent == 1)
{
rotater.SetOutputSpacing(input.GetSpacing()[0], input.GetSpacing()[1], input.GetSpacing()[2]);
rotater.SetOutputOrigin(input.GetOrigin()[0], input.GetOrigin()[1], input.GetOrigin()[2]);
rotater.SetOutputExtent(new_dims[0], new_dims[1], new_dims[2], new_dims[3], new_dims[4], new_dims[5]);
}
rotater.Update();
vtkImageData output = vtkImageData.New();
output.DeepCopy(rotater.GetOutput());
rotater.Dispose();
transform.Dispose();
return(output);
}
