Configuration JSON File

By loading a JSON file, you can set VolView's configuration:

• View layouts (grid size, view types, or hierarchical layouts)
• Disabled view types
• Labels for tools
• Visibility of Sample Data section
• Keyboard shortcuts

View Layouts

Define one or more named layouts using the layouts key. VolView will use the first layout as the default. Each named layout will be in the layout selector menu. Layout are specified in three formats:

1. Grid with View Types (2D String Array)

Use a 2D array of view type strings to specify both the grid layout and which views appear in each position:

{
  "layouts": {
    "Four Up": [
      ["axial", "coronal"],
      ["sagittal", "volume"]
    ]
  }
}

Available view type strings: "axial", "coronal", "sagittal", "volume", "oblique"

2. Simple Grid (gridSize)

Use gridSize to set the layout grid as [width, height]. For example, [2, 2] creates a 2x2 grid of views:

{
  "layouts": {
    "Four by Four": {
      "gridSize": [2, 2]
    }
  }
}

3. Nested Hierarchical Layout

For complex layouts, use a nested structure with full control over view placement and properties:

{
  "layouts": {
    "Volume Primary": {
      "direction": "row",
      "items": [
        "volume",
        {
          "direction": "column",
          "items": ["axial", "coronal", "sagittal"]
        }
      ]
    }
  }
}

Direction values:

• "row" - items arranged horizontally
• "column" - items stacked vertically

You can also specify full view objects with custom options:

{
  "layouts": {
    "Custom 3D Orientation": {
      "direction": "column",
      "items": [
        {
          "type": "3D",
          "name": "Top View",
          "viewDirection": "Superior",
          "viewUp": "Anterior"
        },
        {
          "direction": "row",
          "items": [
            { "type": "2D", "orientation": "Axial" },
            { "type": "2D", "orientation": "Coronal" }
          ]
        }
      ]
    }
  }
}

View object properties:

• 2D views: type: "2D", orientation: "Axial" | "Coronal" | "Sagittal", name (optional)
• 3D views: type: "3D", viewDirection (optional), viewUp (optional), name (optional)
• Oblique views: type: "Oblique", name (optional)

Multiple Layouts Example

You can define multiple named layouts that users can switch between:

{
  "layouts": {
    "Four up": [
      ["axial", "coronal"],
      ["sagittal", "volume"]
    ],
    "Volume focus": {
      "direction": "row",
      "items": [
        "volume",
        {
          "direction": "column",
          "items": ["axial", "coronal", "sagittal"]
        }
      ]
    }
  }
}

Disabled View Types

Use disabledViewTypes to prevent certain view types from being available in the view type switcher:

{
  "disabledViewTypes": ["3D", "Oblique"]
}

This removes the specified view types from the dropdown menu and replaces them in the default layout with allowed types. Valid values: "2D", "3D", "Oblique"

Labels for tools

Each tool type (Rectangle, Polygon, etc.) can have tool specific labels. To share labels across tools, define the defaultLabels key and don't provide labels for a tool that should use the default labels.

{
  "labels": {
    "defaultLabels": {
      "lesion": { "color": "#ff0000" },
      "tumor": { "color": "green", "strokeWidth": 3 }
    }
  }
}

Segment Group File Format

The segmentGroupSaveFormat key specifies the file extension of the segment group images VolView will include in the volview.zip file.

{
  "io": {
    "segmentGroupSaveFormat": "nii"
  }
}

Working segment group file formats:

hdf5, iwi.cbor, mha, nii, nii.gz, nrrd, vtk

Automatic Segment Groups by File Name

When loading files, VolView can automatically convert images to segment groups if they follow a naming convention. For example, an image with name like foo.segmentation.bar will be converted to a segment group for a base image named like foo.baz. The segmentation extension is defined by the io.segmentGroupExtension key, which takes a string. Files foo.[segmentGroupExtension].bar will be automatilly converted to segment groups for a base image named foo.baz. The default is '' and will disable the feature.

This will define myFile.seg.nrrd as a segment group for a myFile.nii base file.

{
  "io": {
    "segmentGroupExtension": "seg"
  }
}

Keyboard Shortcuts

Configure the keys to activate tools, change selected labels, and more. All shortcut actions are under the ACTIONS variable.

To configure a key for an action, add its action name and the key(s) under the shortcuts section. For key combinations, use + like Ctrl+f.

{
  "shortcuts": {
    "polygon": "Ctrl+p",
    "showKeyboardShortcuts": "t"
  }
}

Example JSON:

{
  "labels": {
    "defaultLabels": {
      "lesion": { "color": "#ff0000" },
      "tumor": { "color": "green", "strokeWidth": 3 }
    }
  },
  "layouts": {
    "single-view": {
      "gridSize": [1, 1]
    }
  }
}

All options:

{
  "labels": {
    "defaultLabels": {
      "lesion": { "color": "#ff0000" },
      "tumor": { "color": "green", "strokeWidth": 3 },
      "innocuous": { "color": "white" }
    },
    "rulerLabels": {
      "big": { "color": "#ff0000" },
      "small": { "color": "white" }
    },
    "rectangleLabels": {
      "red": { "color": "#ff0000", "fillColor": "transparent" },
      "green": { "color": "green", "fillColor": "transparent" },
      "white-yellow-fill": {
        "color": "white",
        "fillColor": "#00ff0030"
      }
    },
    "polygonLabels": {
      "poly1": { "color": "#ff0000" },
      "poly2Label": { "color": "green" }
    }
  },
  "layouts": {
    "Volume primary": {
      "direction": "row",
      "items": [
        "volume",
        {
          "direction": "column",
          "items": ["axial", "coronal", "sagittal"]
        }
      ]
    },
    "Four up": [
      ["axial", "coronal"],
      ["sagittal", "volume"]
    ]
  },
  "disabledViewTypes": ["Oblique"],
  "dataBrowser": {
    "hideSampleData": false
  },
  "shortcuts": {
    "polygon": "Ctrl+p",
    "showKeyboardShortcuts": "t"
  },
  "io": {
    "segmentGroupSaveFormat": "nrrd"
  }
}