Labels

The label annotation renderer derives display text from semantic detections. BaseLabelStyle can use a class name, caller metadata, or a custom resolver and can include confidence without storing presentation strings in model output.

Add the label renderer

session.setPresentation({
  renderers: [
    annotationRenderers.label({
      style: new BaseLabelStyle({
        background: { alpha: 0.9 },
        includeConfidence: true,
        textStyle: { fontSize: 14 },
      }),
    }),
  ],
});
Copy

Labels need a resolvable detection rectangle for placement, but the box layer does not need to be visible. Use placement and offset options to move text without changing the geometry.

Labels round all four corners unless an edge touches a displayed detection box. The corners along that attachment stay square: a label above a box has square bottom corners, and a label below it has square top corners. Offsets that detach the label restore all four rounded corners. Set background.topCornersOnly to true to always round only the top pair, or false to always round all four, and choose the radius with background.cornerRadius.

See Interactive Picking for hover-only labels and selection-aware presentation.