Connected Components Workflow

Note

SW Release Applicability: This tutorial is applicable to modules in both NVIDIA DriveWorks and NVIDIA DRIVE Software releases.

Workflow

The workflow of the connected components module is:

• Create connected components handle.

dwImageProperties inputProps{};
    inputProps.width  = width;
    inputProps.height = height;
    inputProps.type   = DW_IMAGE_CUDA;
    inputProps.format = DW_IMAGE_FORMAT_R_UINT8;

dwConnectedComponentsHandle_t ccl;
dwConnectedComponents_initialize(&ccl, &inputProps, cc);

• Create input and output images.

dwImageHandle_t inputImageHandle;
dwImage_create(&inputImage, inputProps, cc);

// fill input image with actual data
// ...

dwImageProperties outputProps{};
    outputProps.width  = width;
    outputProps.height = height;
    outputProps.type   = DW_IMAGE_CUDA;
    outputProps.format = DW_IMAGE_FORMAT_RGBA_UINT8;

dwImageHandle labelsImageHandle;
dwImage_create(&labelsImageHandle, outputProps, cc);

• Perform labeling.

dwConnectedComponents_setThreshold(127, ccl);

dwImageCUDA* inputImage = nullptr;
dwImage_getCUDA(&inputImage, inputImageHandle);

dwConnectedComponents_bindInput(inputImage, ccl);

dwImageCUDA* labelImage = nullptr;
dwImage_getCUDA(&labelImage, labelsImageHandle);

dwConnectedComponents_bindOutput(labelImage, ccl);

dwConnectedComponents_process(ccl);

dwConnectedComponents_setThreshold is a function to define threshold for image binarization. Pixels which values are below the specified threshold are considered to be background pixels.

For a demonstration of this workflow, see Connected Components Sample.