ImageDev

ClosingLine3d

Performs a three-dimensional closing using a structuring element matching with a line.

Access to parameter description

For an introduction: This algorithm successively runs a DilationLine3d and an ErosionLine3d with the same kernel in the opposite direction. A linear opening controls the direction of the opening, therefore making it possible to fill holes and bays thinner than the structuring element in its direction.
The dilation line is oriented in the direction given by ($\theta$, $\varphi$) in spherical coordinates as often used in mathematics (azimuthal angle, $\theta$ and polar angle, $\varphi$). This direction is described with the following formula: $$V=\left[\begin{array}{c}; v_x\\ v_y\\ v_z\end{array}\right] = \left[\begin{array}{c}; \sin(\varphi)\cos(\theta)\\ \sin(\varphi)\sin(\theta)\\ \cos(\varphi)\end{array}\right]$$ This direction can be illustrated on the unit sphere:

<b> Figure 1.</b> Azimuthal and polar angles on the unit sphere
Figure 1. Azimuthal and polar angles on the unit sphere

With a classic implementation, morphological closing systematically considers areas out of the image as a replication of the image borders at each step of the algorithm. Therefore, when applying a closing, some objects close to the image borders may be connected to the border at the dilation step and not be retro propagated after the dilation, while one would expect to keep them disconnected from the border. The borderPolicy parameter manages this case. The default mode, LIMITED, corresponds to the classic behavior. The EXTENDED mode properly manages image borders by extending them by a size equal to the structuring element's. This mode can be slower and more memory consuming, especially when the structuring element size is high.
This option is illustrated in the Closing2d documentation (Figure 2).

See also

Function Syntax

This function returns outputImage. 
// Function prototype
std::shared_ptr< iolink::ImageView >
closingLine3d( std::shared_ptr< iolink::ImageView > inputImage,
               double thetaAngle,
               double phiAngle,
               uint32_t kernelRadius,
               ClosingLine3d::BorderPolicy borderPolicy,
               std::shared_ptr< iolink::ImageView > outputImage = NULL );
This function returns outputImage. 
// Function prototype.
closing_line_3d( input_image,
                 theta_angle = 0,
                 phi_angle = 0,
                 kernel_radius = 3,
                 border_policy = ClosingLine3d.BorderPolicy.LIMITED,
                 output_image = None )
This function returns outputImage. 
// Function prototype.
public static IOLink.ImageView
ClosingLine3d( IOLink.ImageView inputImage,
               double thetaAngle = 0,
               double phiAngle = 0,
               UInt32 kernelRadius = 3,
               ClosingLine3d.BorderPolicy borderPolicy = ImageDev.ClosingLine3d.BorderPolicy.LIMITED,
               IOLink.ImageView outputImage = null );

Class Syntax

Parameters

Class Name ClosingLine3d

Parameter Name Description Type Supported Values Default Value
input
inputImage
The input image. The image type can be integer or float. Image Binary, Label, Grayscale or Multispectral nullptr
input
borderPolicy
The border policy to apply.
LIMITED The limited mode is faster to compute, but can produce the unexpected results for particles close to the image border.
EXTENDED The Extended mode is slower to compute, but produces the expected results for particles close to the image border.
Enumeration LIMITED
input
thetaAngle
The azimuthal angle in degrees. Float64 Any value 0
input
phiAngle
The polar angle in degrees. Float64 Any value 0
input
kernelRadius
The length of the linear structuring element in voxels. UInt32 >=1 3
output
outputImage
The output image. Its dimensions and type are forced to the same values as the input image. Image nullptr

Object Examples

auto foam = readVipImage( std::string( IMAGEDEVDATA_IMAGES_FOLDER ) + "foam.vip" );

ClosingLine3d closingLine3dAlgo;
closingLine3dAlgo.setInputImage( foam );
closingLine3dAlgo.setThetaAngle( 0 );
closingLine3dAlgo.setPhiAngle( 0 );
closingLine3dAlgo.setKernelRadius( 3 );
closingLine3dAlgo.setBorderPolicy( ClosingLine3d::BorderPolicy::EXTENDED );
closingLine3dAlgo.execute();

std::cout << "outputImage:" << closingLine3dAlgo.outputImage()->toString();

foam = imagedev.read_vip_image(imagedev_data.get_image_path("foam.vip"))

closing_line_3d_algo = imagedev.ClosingLine3d()
closing_line_3d_algo.input_image = foam
closing_line_3d_algo.theta_angle = 0
closing_line_3d_algo.phi_angle = 0
closing_line_3d_algo.kernel_radius = 3
closing_line_3d_algo.border_policy = imagedev.ClosingLine3d.EXTENDED
closing_line_3d_algo.execute()

print( "output_image:", str( closing_line_3d_algo.output_image ) )

ImageView foam = Data.ReadVipImage( @"Data/images/foam.vip" );

ClosingLine3d closingLine3dAlgo = new ClosingLine3d
{
    inputImage = foam,
    thetaAngle = 0,
    phiAngle = 0,
    kernelRadius = 3,
    borderPolicy = ClosingLine3d.BorderPolicy.EXTENDED
};
closingLine3dAlgo.Execute();

Console.WriteLine( "outputImage:" + closingLine3dAlgo.outputImage.ToString() );

Function Examples

auto foam = readVipImage( std::string( IMAGEDEVDATA_IMAGES_FOLDER ) + "foam.vip" );

auto result = closingLine3d( foam, 0, 0, 3, ClosingLine3d::BorderPolicy::EXTENDED );

std::cout << "outputImage:" << result->toString();

foam = imagedev.read_vip_image(imagedev_data.get_image_path("foam.vip"))

result = imagedev.closing_line_3d( foam, 0, 0, 3, imagedev.ClosingLine3d.EXTENDED )

print( "output_image:", str( result ) )

ImageView foam = Data.ReadVipImage( @"Data/images/foam.vip" );

IOLink.ImageView result = Processing.ClosingLine3d( foam, 0, 0, 3, ClosingLine3d.BorderPolicy.EXTENDED );

Console.WriteLine( "outputImage:" + result.ToString() );