Title: Visualizing Semantic Data — Omniverse Extensions URL Source: https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/visualization.html Published Time: Wed, 01 Oct 2025 18:15:38 GMT Markdown Content: Visualizing Semantic Data[#](https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/visualization.html#visualizing-semantic-data "Link to this heading") -------------------------------------------------------------------------------------------------------------------------------------------------------------------- Learning Objectives[#](https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/visualization.html#learning-objectives "Link to this heading") -------------------------------------------------------------------------------------------------------------------------------------------------------- This tutorial introduces the Synthetic Data interface for Replicator. After this tutorial, you will know how to define, apply, and visualize semantic data in Replicator. Getting Started[#](https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/visualization.html#getting-started "Link to this heading") ------------------------------------------------------------------------------------------------------------------------------------------------ ### The Editor[#](https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/visualization.html#the-editor "Link to this heading") Semantic annotations (data “of interest” pertaining to a given mesh) are required to properly use the synthetic data extension. These annotations inform the extension about what objects in the scene need bounding boxes, pose estimations, etc… The Semantics Schema Editor provides a way to apply these annotations to prims on the stage through a UI. To access the editor, follow the steps detailed in [Adding Semantics to a Scene](https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/semantics_schema_editor.html#semantic). The editor will appear as a tab in the _Properties_ pane by default. Semantic annotations can be applied either manually to a collection of selected prims or automatically by the path and type of each prim on the stage ### The Visualizer[#](https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/visualization.html#the-visualizer "Link to this heading") Visualizing the output of synthetic sensors is done through the [![Image 1: visualizer](https://docs.omniverse.nvidia.com/extensions/latest/_images/isaac_synth-data_visualizer_0.png)](https://docs.omniverse.nvidia.com/extensions/latest/_images/isaac_synth-data_visualizer_0.png) Visualizer tool in the Viewport window. [![Image 2: ../_images/Replicator_visualizer.PNG](https://docs.omniverse.nvidia.com/extensions/latest/_images/Replicator_visualizer.PNG)](https://docs.omniverse.nvidia.com/extensions/latest/_images/Replicator_visualizer.PNG) Annotations that can be rendered to an image are listed here. Activating a channel and pressing the `visualize` button will render those channels in a test image, like the one shown below ![Image 3: ../_images/Replicator_visualizer_demo.gif](https://docs.omniverse.nvidia.com/extensions/latest/_images/Replicator_visualizer_demo.gif) Note * If the camera name is too long, the [![Image 4: visualizer](https://docs.omniverse.nvidia.com/extensions/latest/_images/isaac_synth-data_visualizer_0.png)](https://docs.omniverse.nvidia.com/extensions/latest/_images/isaac_synth-data_visualizer_0.png) icon in the Viewport window might get obscured **LdrColor** This is just the standard view from the viewport camera in RGB. Note that selected prims and the viewport grid are also captured by this camera, and need to be disabled manually in the adjacent ‘show/hide’ menu **DistanceToImagePlane** Distance to the image plane is distance in the camera’s forward axis. **DistanceToCamera** Distance to camera is a distance to the camera’s centre. **CrossCorrespondence** CrossCorrespondence provides, given two cameras in two viewports, the difference in pixel positions for pixels that exist in both cameras. **Normals** This colors each pixel corresponding to the direction each surface in the stage is facing **TargetMotion** This is the optical flow, and only really applies to scenes with dynamics. **Semantic and Instance Segmentation** the 2D segmentation regions for each type of object in the scene, and each instance of each object in the scene respectively. `Raw` here means that semantics are not inherited from parent prims, while `Parsed` does. **2D Bounding Boxes** 2D bounding boxes are the 2D region in the image that holds an object with a semantic label. `Tight` means that the box will occlude or intersect parts of the object to reduce the amount of space in the bbox that the object doesn’t occupy. `Loose` is the opposite, expanding the box to make sure that all parts of the mesh are captured **3D Bounding Boxes** 3D bounding boxes define a set of 8 points that define the corners of a 3D box that holds an object with a semantic label. `Raw` and `Parsed` here means the same as it did for semantic segmentation. Links/Buttons: - [#](https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/visualization.html#the-visualizer) - [Adding Semantics to a Scene](https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/semantics_schema_editor.html#semantic) - [](https://docs.omniverse.nvidia.com/extensions/latest/_images/Replicator_visualizer.PNG)