Connected Component 2d

image =	connectedComponent2dImg (inBinLabImg)
image =	connectedComponent2dImg (inBinLabImg,inOptNeighborhood2d)
scalar =	connectedComponent2dImg (inBinLabImg,inOptNeighborhood2d,outLabelImg)

Detailed Description

Connected component image 2d labeling algorithm.

Connected component labeling algorithm allows to uniquely labeled subsets of connected components with respect to a given neighborhood policy.

Output labels start with 1 and are consecutive with respect to scanning order (from lower x then y to higher).

For more informations on used neighborhood 2d types report to 2d neighborhood models.

Resulting image buffer type must be one of the following :

• ipsdk::image::eImageBufferType::eIBT_Label16
• ipsdk::image::eImageBufferType::eIBT_Label32

Here is an example of connected component extraction operation applied to a binary input image (with 8 connexity neighborhood type) :

Here is an example of connected component extraction operation applied to a binary input image (with 4 connexity neighborhood type) :

The algorithm also allows to relabel a label image. This way all connected component will be assigned to a unique label.

Here is an example of relabel of a label image using the connected component algorithm in 2d case :

Note

Last wrapper function returns number of extracted connected components (unique labels).

If number of extracted connected components exceed output image data type capacity (case of a number of connected components greater than 65535 and an output image associated to a ipsdk::image::eImageBufferType::eIBT_Label16 data type), output image data type is automatically upgraded to ipsdk::image::eImageBufferType::eIBT_Label32.

See also

http://en.wikipedia.org/wiki/Connected-component_labeling

Example of Python code :

Example imports

import PyIPSDK
import PyIPSDK.IPSDKIPLAdvancedMorphology as advmorpho

Code Example

    # opening of input image
    inImg = PyIPSDK.loadTiffImageFile(inputImgPath)
    
    # connected components 2d computation
    outImg = advmorpho.connectedComponent2dImg(inImg)

Example of C++ code :

Example informations

Header file

#include <IPSDKIPL/IPSDKIPLAdvancedMorphology/Processor/ConnectedComponent2dImg/ConnectedComponent2dImg.h>

Code Example

    // opening input image
    ImagePtr pInBinImg = loadTiffImageFile(inputImgPath);

    // compute connected component label image associated to input image
    ImagePtr pOutLabelImg = connectedComponent2dImg(pInBinImg);