Camera Examples

The goal of this tutorial is to provide examples of common use cases for cameras in Omniverse Replicator. Below are a few examples of camera useage applied within a scene using Replicator APIs.

Learning Objectives

Through this page you will see some highlighted camera examples and how to use them. However, for all information about replicator camera use consult the API documentation .

Set up

Each of the camera examples shown below are standalone scripts that can be run following the set up described in Setting up the Script Editor and Running and Previewing Replicator.

Creating a Camera and Setting Properties

Creating a camera and initializing it’s properties is straightforward. Below is a small snippet as an example, but the API documents all available options.

import omni.replicator.core as rep

# Create camera
camera = rep.create.camera(
    position=rep.distribution.uniform((0,0,0), (100, 100, 100)),
    rotation=(45, 45, 0),
    focus_distance=rep.distribution.normal(400.0, 100),
    f_stop=1.8,
)

Randomizing a camera’s position uniformly

An example showing how to move a camera to random location within an area, chosen by a uniform distribution.

import omni.replicator.core as rep

# Randomize the camera position using basic uniform distribution

with rep.new_layer():

    # Create camera
    # https://docs.omniverse.nvidia.com/py/replicator/source/extensions/omni.replicator.core/docs/API.html#omni.replicator.core.create.camera
    camera = rep.create.camera(focus_distance=200,f_stop=0.5)

    # Add Default Light
    distance_light = rep.create.light(rotation=(315,0,0), intensity=3000, light_type="distant")

    cube = rep.create.cube(semantics=[('class', 'cube')],  position=(0, 0, 0))
    render_product  = rep.create.render_product(camera, (1024, 1024))

    # Initialize and attach writer
    writer = rep.WriterRegistry.get("BasicWriter")
    writer.initialize(output_dir="_output_camera_uniformpos", rgb=True, bounding_box_2d_tight=True)
    writer.attach([render_product])

    with rep.trigger.on_frame(num_frames=10):
        with camera:
            rep.modify.pose(position=rep.distribution.uniform((-500, 200, -500), (500, 500, 500)), look_at=(0,0,0))

Randomizing a camera’s position using a list

An example showing how to move a camera to random location chosen from a list, using the choice distribution.

import omni.replicator.core as rep

# Pick a random camera location each frame, from a list

with rep.new_layer():

    # Create camera
    # https://docs.omniverse.nvidia.com/py/replicator/source/extensions/omni.replicator.core/docs/API.html#omni.replicator.core.create.camera
    camera_positions = [(-500, 200, -500), (500, 500, 500)]

    # Add Default Light
    distance_light = rep.create.light(rotation=(315,0,0), intensity=3000, light_type="distant")

    camera = rep.create.camera(focus_distance=200,f_stop=0.5)

    cube = rep.create.cube(semantics=[('class', 'cube')],  position=(0, 0, 0))
    render_product  = rep.create.render_product(camera, (1024, 1024))

    # Initialize and attach writer
    writer = rep.WriterRegistry.get("BasicWriter")
    writer.initialize(output_dir="_output_camera_posfromlist", rgb=True, bounding_box_2d_tight=True)
    writer.attach([render_product])

    with rep.trigger.on_frame(num_frames=10):
        with camera:
            rep.modify.pose(position=rep.distribution.choice(camera_positions), look_at=(0,0,0))

Multiple Cameras with Basic Writer

Multiple cameras are supported in Replicator. Below is a small example of the basic writer with two cameras in the scene, writing outputs for each per frame.

import omni.replicator.core as rep

camera1_pos = [(0, 100, 500),(500, 100, 500),(-500, 100, 500),]
camera2_pos = [(0, 500, 0),(500, 500, 0),(-500, 500, 0),]

with rep.new_layer():

    # Add Default Light
    distance_light = rep.create.light(rotation=(315,0,0), intensity=3000, light_type="distant")

    cube = rep.create.cube(position=(200, 0, 0), semantics=[('class', 'cube')])
    sphere = rep.create.sphere(position=(0, 0, 0), semantics=[('class', 'sphere')])
    cone = rep.create.cone(position=(-200, 0, 0), semantics=[('class', 'cone')])

    camera = rep.create.camera(position=camera1_pos[0], look_at=(0,0,0))
    camera2 = rep.create.camera(position=camera2_pos[0], look_at=(0,0,0))

    with rep.trigger.on_frame(num_frames=3):
        with camera:
            rep.modify.pose(look_at=(0,0,0), position=rep.distribution.sequence(camera1_pos))
        with camera2:
            rep.modify.pose(look_at=(0,0,0), position=rep.distribution.sequence(camera2_pos))

# Will render 512x512 images and 320x240 images
render_product = rep.create.render_product(camera, (512, 512))
render_product2 = rep.create.render_product(camera2, (320, 240))

basic_writer = rep.WriterRegistry.get("BasicWriter")
basic_writer.initialize(
    output_dir=f"~/replicator_examples/multi_render_product/basic",
    rgb=True,
    bounding_box_2d_loose=True,
    bounding_box_2d_tight=True,
    bounding_box_3d=True,
    distance_to_camera=True,
    distance_to_image_plane=True,
    instance_segmentation=True,
    normals=True,
    semantic_segmentation=True,
)
# Attach render_product to the writer
basic_writer.attach([render_product, render_product2])
# Run the simulation graph
rep.orchestrator.run()