ImageDev

BinaryCorrelation2d

Performs a logical correlation between a binary two-dimensional image and a binary kernel.

Access to parameter description

For an introduction: section Image Correlation.

The binary correlation $O$ between image $I$ and kernel $K$ is defined as: $$ O(n,m)=O_1(n,m)+O_2(n,m) $$ $$ O_1(n,m)=\sum_{i=1}^{kx} \sum_{j=1}^{ky} \left( K(i,j)\wedge I(n+i-\frac{kx}{2},m+j-\frac{ky}{2}) \right) $$ $$ O_2(n,m)=\sum_{i=1}^{kx} \sum_{j=1}^{ky} \overline{\left( K(i,j)\vee I(n+i-\frac{kx}{2},m+j- \frac{ky}{2}) \right)} $$ where:
At the end of the process, the correlation image is normalized between -1 and 1.
<b> Figure 1</b> Example of BinaryCorrelation2d
Figure 1 Example of BinaryCorrelation2d

When a part of the kernel lies beyond the edge of the image, the correlation is not computed on the border. In such cases, the values are set to -1E10.

See also

Function Syntax

This function returns a BinaryCorrelation2dOutput structure containing the outputImage and outputMeasurement output parameters.
// Output structure.
struct BinaryCorrelation2dOutput
{
    std::shared_ptr< iolink::ImageView > outputImage;
    CorrelationMsr::Ptr outputMeasurement;
};

// Function prototype.
BinaryCorrelation2dOutput
binaryCorrelation2d( std::shared_ptr< iolink::ImageView > inputBinaryImage,
                     std::shared_ptr< iolink::ImageView > inputKernelImage,
                     BinaryCorrelation2d::OffsetMode offsetMode,
                     std::shared_ptr< iolink::ImageView > outputImage = NULL,
                     CorrelationMsr::Ptr outputMeasurement = NULL );
This function returns a tuple containing the output_image and output_measurement output parameters.
// Function prototype.
binary_correlation_2d( input_binary_image,
                       input_kernel_image,
                       offset_mode = BinaryCorrelation2d.OffsetMode.OFFSET_1,
                       output_image = None,
                       output_measurement = None )
This function returns a BinaryCorrelation2dOutput structure containing the outputImage and outputMeasurement output parameters.
/// Output structure of the BinaryCorrelation2d function.
public struct BinaryCorrelation2dOutput
{
    public IOLink.ImageView outputImage;
    public CorrelationMsr outputMeasurement;
};

// Function prototype.
public static BinaryCorrelation2dOutput
BinaryCorrelation2d( IOLink.ImageView inputBinaryImage,
                     IOLink.ImageView inputKernelImage,
                     BinaryCorrelation2d.OffsetMode offsetMode = ImageDev.BinaryCorrelation2d.OffsetMode.OFFSET_1,
                     IOLink.ImageView outputImage = null,
                     CorrelationMsr outputMeasurement = null );

Class Syntax

Parameters

Class Name BinaryCorrelation2d

Parameter Name Description Type Supported Values Default Value
input
inputBinaryImage
The input binary image. Image Binary nullptr
input
inputKernelImage
The correlation kernel. Image Binary nullptr
input
offsetMode
The calculation offset, in pixels. The greater this value, computation is faster but detection is less precise.
OFFSET_1 The correlation is computed with a step of 1.
OFFSET_2 The correlation is computed with a step of 2.
OFFSET_4 The correlation is computed with a step of 4.
OFFSET_8 The correlation is computed with a step of 8.
Enumeration OFFSET_1
output
outputImage
The output correlation image. Its dimensions are forced to the same values as the input. Its data type is forced to floating point. Image nullptr
output
outputMeasurement
The correlation matching results. CorrelationMsr nullptr

Object Examples

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

BinaryCorrelation2d binaryCorrelation2dAlgo;
binaryCorrelation2dAlgo.setInputBinaryImage( polystyrene_sep );
binaryCorrelation2dAlgo.setInputKernelImage( polystyrene_sep );
binaryCorrelation2dAlgo.setOffsetMode( BinaryCorrelation2d::OffsetMode::OFFSET_1 );
binaryCorrelation2dAlgo.execute();

std::cout << "outputImage:" << binaryCorrelation2dAlgo.outputImage()->toString();
std::cout << "minComputed: " << binaryCorrelation2dAlgo.outputMeasurement()->minComputed( 0 ) ;
polystyrene_sep = imagedev.read_vip_image(imagedev_data.get_image_path("polystyrene_sep.vip"))

binary_correlation_2d_algo = imagedev.BinaryCorrelation2d()
binary_correlation_2d_algo.input_binary_image = polystyrene_sep
binary_correlation_2d_algo.input_kernel_image = polystyrene_sep
binary_correlation_2d_algo.offset_mode = imagedev.BinaryCorrelation2d.OFFSET_1
binary_correlation_2d_algo.execute()

print( "output_image:", str( binary_correlation_2d_algo.output_image ) )
print( "minComputed: ", str( binary_correlation_2d_algo.output_measurement.min_computed( 0 ) ) )
ImageView polystyrene_sep = Data.ReadVipImage( @"Data/images/polystyrene_sep.vip" );

BinaryCorrelation2d binaryCorrelation2dAlgo = new BinaryCorrelation2d
{
    inputBinaryImage = polystyrene_sep,
    inputKernelImage = polystyrene_sep,
    offsetMode = BinaryCorrelation2d.OffsetMode.OFFSET_1
};
binaryCorrelation2dAlgo.Execute();

Console.WriteLine( "outputImage:" + binaryCorrelation2dAlgo.outputImage.ToString() );
Console.WriteLine( "minComputed: " + binaryCorrelation2dAlgo.outputMeasurement.minComputed( 0 ) );

Function Examples

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

auto result = binaryCorrelation2d( polystyrene_sep, polystyrene_sep, BinaryCorrelation2d::OffsetMode::OFFSET_1 );

std::cout << "outputImage:" << result.outputImage->toString();
std::cout << "minComputed: " << result.outputMeasurement->minComputed( 0 ) ;
polystyrene_sep = imagedev.read_vip_image(imagedev_data.get_image_path("polystyrene_sep.vip"))

result_output_image, result_output_measurement = imagedev.binary_correlation_2d( polystyrene_sep, polystyrene_sep, imagedev.BinaryCorrelation2d.OFFSET_1 )

print( "output_image:", str( result_output_image ) )
print( "minComputed: ", str( result_output_measurement.min_computed( 0 ) )  )
ImageView polystyrene_sep = Data.ReadVipImage( @"Data/images/polystyrene_sep.vip" );

Processing.BinaryCorrelation2dOutput result = Processing.BinaryCorrelation2d( polystyrene_sep, polystyrene_sep, BinaryCorrelation2d.OffsetMode.OFFSET_1 );

Console.WriteLine( "outputImage:" + result.outputImage.ToString() );
Console.WriteLine(  "minComputed: " + result.outputMeasurement.minComputed( 0 )  );