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ROI & Drawing

ROI Mask

Draws an ROI (ellipse, rectangle, polygon, or lasso) directly on the node surface and outputs a binary mask plus a cropped image.

Details

Inputs:

  • image — the image to draw on (sets the background)

Outputs:

  • mask — binary L-mode PIL image (0 / 255)
  • cropped_image — input image with non-ROI pixels set to black
Direction Port Type
Input image image
Output cropped_image image

Crop

Crops an image or mask to a rectangle drawn directly on the node.

Details

Click and drag on the node surface to draw the crop rectangle. Drag the edges to resize it, or drag the body to move it. Press Delete to clear the selection (outputs the full image when no rectangle is drawn). Supports both ImageData and MaskData inputs.

Direction Port Type
Input image image
Output image image

Mask Crop

Crops an image to a mask's bounding box.

Details

When Black outside is checked, pixels outside the mask are set to zero. When unchecked, all pixels within the bounding box are kept. Padding adds extra pixels around the bounding box.

Direction Port Type
Input image image
Input mask mask
Output image image

Draw Shape

Draw shapes, text, and annotations on an image.

Details

Shapes: rectangle, ellipse, polygon, arrow, bezier curve, and free text. Each shape has its own color, line width, line style (solid/dashed/dotted), and optional fill with adjustable opacity. Shapes can be moved, resized, and edited interactively on the canvas.

Inputs:

  • image — background image (optional)
  • mask (multi-input) — binary masks shown as colored contours
  • label_image — segmentation labels shown as colored overlay

Controls:

  • Line width, style, and color per shape
  • Fill toggle + opacity for closed shapes (rectangle, ellipse, polygon)
  • Auto Fill — fill all mask contours at once
  • Fill All — apply fill to every mask input
  • Label overlay opacity — transparency of segmentation label colors
  • Geometry spinboxes (X, Y, W, H) for precise positioning
  • Font size for texts
  • No Preview — skip interactive canvas rendering for speed

Hold Shift while drawing to constrain to square/circle.

Direction Port Type
Input image image
Input mask mask
Input label_image label_image
Output image image

Mask Editor

Interactively edits a mask by drawing shapes and applying boolean operations.

Details

Supports add, subtract, and intersect modes with rect, ellipse, polygon, and lasso tools. Accepts an optional background image for visual reference and an optional mask input as the starting state.

Direction Port Type
Input image image
Input mask mask
Output mask mask

Scale Bar

Draws a calibrated scale bar on a microscopy image.

Details

Reads the scale_um metadata from the upstream ImageData to calculate the correct pixel length for the bar. If no scale info is available, the node reports an error.

Options:

  • bar_length_um — desired bar length in micrometers
  • position — corner placement
  • bar_color — color of the bar and label
  • bar_height — thickness in pixels
  • show_label — display "100 µm" text
  • font_size — label size
  • padding_x / padding_y — margin from image edge
Direction Port Type
Input image image
Output image image

Properties: Bar Length (µm), Position, Show Label, Text-Bar Gap (px)


Mask Overlay

Draw a mask contour (or fill) on an image.

Details

A lightweight alternative to Draw Shape for simple mask visualization. Connect an image and a mask, and the mask boundary is drawn as a colored contour on the output image. Optionally fill the masked region with a semi-transparent color.

Controls:

  • Line width, style (solid/dashed/dotted), and color
  • Fill toggle with adjustable opacity
Direction Port Type
Input image image
Input mask mask
Output image image

Label Overlay

Overlay a label image on top of a base image with automatic coloring.

Details

Each unique label gets a distinct color from the selected colormap. Background (label 0) is always transparent.

Controls:

  • Opacity of the label overlay
  • Colormap (tab10, tab20, Set1, Set3, etc.)
  • Line width and style for contour-only mode
  • Fill toggle: filled regions or contour outlines only
Direction Port Type
Input label_image label
Output image image

Label Editor

Interactively edits a multi-label image by drawing shapes and applying operations.

Details

Supports rect, ellipse, polygon, lasso, brush, and flood-fill tools. Each label is assigned a distinct color. Outputs the label array and a summary table.

Direction Port Type
Input image image
Input label_image label_image
Output label_image label_image
Output table table