Distance transform (cv::distanceTransform). Each non-zero pixel gets its distance to the nearest zero pixel, with selectable distance type and mask size; the classic pre-pass for watershed seeding and stroke-width estimation.

Module：OpenCV segmentation · Task type：opencv_distance_transform

Ports

Inputs

PortTypeRequired
inImage / cv::Mat✓

Outputs

PortTypeRequired
outcv::Mat✓

Parameters

参数类型默认值范围 / 选项说明
distance_typeenum2L2 / L1 / C
mask_sizeenum0PRECISE / 3 / 5

Example graph

A minimal runnable pipeline (read → process → write). Drag it into GraphStudio or open via --open; replace data/test.png with a real path.

{
  "version": "2.0",
  "tasks": [
    {
      "id": "read",
      "type": "opencv_image_read",
      "params": {
        "file_path": "data/test.png"
      }
    },
    {
      "id": "node",
      "type": "opencv_distance_transform",
      "params": {
        "distance_type": 2,
        "mask_size": 0
      }
    },
    {
      "id": "save",
      "type": "opencv_image_write",
      "params": {
        "file_path": "out_out.png"
      }
    }
  ],
  "edges": [
    {
      "from": "read",
      "from_port": "out",
      "to": "node",
      "to_port": "in"
    },
    {
      "from": "node",
      "from_port": "out",
      "to": "save",
      "to_port": "in"
    }
  ]
}

Part of the GraphStudio node guide series; parameters reflect the latest release.