Area2d

Computes the area of foreground pixels in a two-dimensional binary image.

Access to parameter description

For an introduction: section Image Analysis.

In the continuous, or theoretical, case, area is defined as: $$A(x)=\int_{R^2}dxdy$$ In the discrete, or actual, case, area is approximated by the number of pixels in X: $$A(x)=\sum_{i,j}g(x_i,y_j)$$ where:
$$\begin{array}{l} g(x_i,y_j)=1 ~ \mbox{if the pixel lies within the object X}\\ g(x_i,y_j)=0 ~ \mbox{otherwise}\end{array}$$ The area measurement can be weighted by a size factor which characterizes the area of a single pixel. This information is given by the calibration spacing of the input image. If this image peoperty is correctly filled, the measurement is physically homogeneous to the area.

This algorithm can be applied on a binary image and returns:

• The number of non-zero pixels in the image.
• The physical area taking into account the pixel size from input calibration.
• The area fraction between non-zero pixels and the total number of pixels in the input image.

See also

• ObjectVolume
• IntensityIntegral2d
• IntensityIntegral3d
• VolumeFractionByLabel
• Area3d

See related example

• GlobalAnalysis

// Function prototype.
Area2dMsr::Ptr
area2d( std::shared_ptr< iolink::ImageView > inputBinaryImage, Area2dMsr::Ptr outputMeasurement = NULL );

// Function prototype.
area_2d( input_binary_image, output_measurement = None )

// Function prototype.
public static Area2dMsr
Area2d( IOLink.ImageView inputBinaryImage, Area2dMsr outputMeasurement = null );

// Command constructor.
Area2d();

// Get method of the inputBinaryImage parameter.
std::shared_ptr< iolink::ImageView > inputBinaryImage() const;
// Set method of the inputBinaryImage parameter.
void setInputBinaryImage( std::shared_ptr< iolink::ImageView > inputBinaryImage );

// Get method of the outputMeasurement parameter.
Area2dMsr::Ptr outputMeasurement() const;

// Method to launch the command.
void execute();

// Property of the inputBinaryImage parameter.
Area2d.input_binary_image
// Property of the outputMeasurement parameter.
Area2d.output_measurement

// Method to launch the command.
execute()

// Command constructor.
Area2d()

// Property of the inputBinaryImage parameter.
Area2d.inputBinaryImage
// Property of the outputMeasurement parameter.
Area2d.outputMeasurement

// Method to launch the command.
Execute()

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

Area2d area2dAlgo;
area2dAlgo.setInputBinaryImage( polystyrene_sep );
area2dAlgo.execute();

std::cout << "area: " << area2dAlgo.outputMeasurement()->area( 0 ) ;

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

area_2d_algo = imagedev.Area2d()
area_2d_algo.input_binary_image = polystyrene_sep
area_2d_algo.execute()

print( "area: ", str( area_2d_algo.output_measurement.area( 0 ) ) )

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

Area2d area2dAlgo = new Area2d
{
    inputBinaryImage = polystyrene_sep
};
area2dAlgo.Execute();

Console.WriteLine( "area: " + area2dAlgo.outputMeasurement.area( 0 ) );

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

auto result = area2d( polystyrene_sep );

std::cout << "area: " << result->area( 0 ) ;

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

result = imagedev.area_2d( polystyrene_sep )

print( "area: ", str( result.area( 0 ) )  )

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

Area2dMsr result = Processing.Area2d( polystyrene_sep );

Console.WriteLine(  "area: " + result.area( 0 )  );