Module ouster.sdk.viz

Ouster sensor data visualization tools. Implemented in C++ OpenGL and wrapped with Python bindings.

For additional information please refer to PointViz Tutorial & API Usage.

---

Core

class PointViz

add()

Add an object to the scene.

Parameters

obj – A cloud, label, image or cuboid.

property camera

Get a reference to the camera controls.

push_key_handler()

Add a callback for handling keyboard input.

remove()

Remove an object from the scene.

Parameters

obj – A cloud, label, image or cuboid.

Returns

True if the object was in the scene and was removed.

run()

Run the visualizer rendering loop.

Must be called from the main thread. Will return when running(False) is called from another thread or when the visualizer window is closed.

run_once()

Run one iteration of the main loop for rendering and input handling.

running()

Check if the rendering loop is running. Shut down the visualizer and break out of the rendering loop.

property target_display

Get a reference to the target display.

update()

Show updated data in the next rendered frame.

add_default_controls()

Add default keyboard and mouse bindings to a visualizer instance.

class LidarScanViz(meta, viz=None)

Visualize LidarScan data.

Uses the supplied PointViz instance to easily display the contents of a LidarScan. Sets up key bindings to toggle which channel fields and returns are displayed, and change 2D image and point size.

Parameters

• meta (SensorInfo) – sensor metadata used to interpret scans

• viz (Optional[PointViz]) – use an existing PointViz instance instead of creating one

cycle_img_mode(i)

Change the displayed field of the i’th image.

Return type

None

cycle_cloud_mode()

Change the channel field used to color the 3D point cloud.

Return type

None

toggle_cloud(i)

Toggle whether the i’th return is displayed.

Return type

None

update_point_size(amount)

Change the point size of the 3D cloud.

Return type

None

update_image_size(amount)

Change the size of the 2D image.

Return type

None

update_ring_size(amount)

Change distance ring size.

Return type

None

toggle_osd(state=None)

Show or hide the on-screen display.

Return type

None

property scan: ouster.client._client.LidarScan

The currently displayed scan.

Return type

LidarScan

draw(update=True)

Process and draw the latest state to the screen.

Return type

bool

run()

Run the rendering loop of the visualizer.

See PointViz.run()

Return type

None

class SimpleViz(arg, rate=None, _buflen=50)

Visualize a stream of LidarScans.

Handles controls for playback speed, pausing and stepping.

Parameters

• arg (Union[SensorInfo, LidarScanViz]) – Metadata associated with the scans to be visualized or a LidarScanViz instance to use.

• rate (Optional[float]) – Playback rate. One of 0.25, 0.5, 0.75, 1.0, 1.5, 2.0, 3.0 or None for “live” playback (the default).

Raises

ValueError – if the specified rate isn’t one of the options

toggle_pause()

Pause or unpause the visualization.

Return type

None

seek_relative(n_frames)

Seek forward of backwards in the stream.

Return type

None

modify_rate(amount)

Switch between preset playback rates.

Return type

None

toggle_osd(state=None)

Show or hide the on-screen display.

Return type

None

run(scans)

Start reading scans and visualizing the stream.

Must be called from the main thread on macos. Will close the provided scan source before returning.

Parameters

scans (Iterable[LidarScan]) – A stream of scans to visualize.

Return type

None

Returns

When the stream is consumed or the visualizer window is closed.

viz.spezia_palette = spezia colors

viz.calref_palette = calref colors

Visual Primitives

Cloud for 3D Point Cloud

class Cloud

Manages the state of a point cloud.

Each point cloud consists of n points with w poses. The ith point will be transformed by the (i % w)th pose. For example for 2048 x 64 Ouster lidar point cloud, we may have w = 2048 poses and n = 2048 * 64 = 131072 points.

We also keep track of a per-cloud pose to efficiently transform the whole point cloud without having to update all ~2048 poses.

def __init__(self, n_points: int) -> None:

Unstructured point cloud for visualization.

Call set_xyz() to update

Parameters

• n – number of points

• extrinsic – sensor extrinsic calibration. 4x4 column-major homogeneous transformation matrix

def __init__(self, si: SensorInfo) -> None:

Structured point cloud for visualization.

Call set_range() to update

Parameters

info – sensor metadata

set_key()

Set the key values, used for colouring.

Parameters

key – array of at least as many elements as there are points, preferably normalized between 0 and 1

set_mask()

Set the RGBA mask values, used as an overlay on top of the key.

Parameters

mask – array of at least 4x as many elements as there are points, preferably normalized between 0 and 1

set_palette()

Set the point cloud color palette.

Parameters

palette – the new palette to use, must have size 3*palette_size

set_point_size()

Set point size.

Parameters

size – point size

set_pose()

Set the ith point cloud pose.

Parameters

pose – 4x4 column-major homogeneous transformation matrix

set_range()

Set the range values.

Parameters

range – array of at least as many elements as there are points, representing the range of the points

set_xyz()

Set the XYZ values.

Parameters

xyz – array of exactly 3n where n is number of points, so that the xyz position of the ith point is i, i + n, i + 2n

Image for 2D image

class Image

Manages the state of an image.

set_hshift()

Set horizontal shift in normalized viewport screen width coordinate.

This may be used to “snap” images to the left/right screen edges.

Some example values:

0 - default, image is centered horizontally on the screen -0.5 - image moved to the left for the 1/4 of a horizontal viewport -1 - image moved to the left for the 1/2 of a horizontal viewport +1 - image moved to the right for the 1/2 of a horizontal viewport +0.5 - image moved to the right for the 1/4 of a horizontal viewport

set_image()

Set the image data.

Parameters

image – 2D array with image data

set_mask()

Set the RGBA mask.

Parameters

mask – M x N x 4 array with RGBA mask

set_position()

Set the display position of the image.

Coordinates are {x_min, x_max, y_max, y_min} in sort-of normalized screen coordinates: y is in [-1, 1], and x uses the same scale (i.e. window width is ignored). This is currently just the same method the previous hard-coded ‘image_frac’ logic was using; I believe it was done this way to allow scaling with the window while maintaining the aspect ratio.

Parameters

• x_min – min x

• x_max – max x

• y_min – min y

• y_max – max y

Cuboid for 3D enclosure

class Cuboid

Manages the state of a single cuboid.

Creates cuboid.

Parameters

• pose – 4x4 pose matrix

• rgba – 4 value tuple of RGBA color

set_rgba()

Set the color of the cuboid.

Parameters

rgba – 4 value tuple of RGBA color

set_transform()

Set the transform defining the cuboid.

Applied to a unit cube centered at the origin.

Parameters

pose – 4x4 pose matrix

Label for 2D and 3D text

class Label

Manages the state of a text label.

def __init__(self, text: str, x: float, y: float, z: float) -> None:

Creates 3D Label.

Parameters

• text – label text

• x – label location

• y – label location

• z – label location

def __init__(self, text: str, x: float, y: float, align_right: bool = ..., align_top: bool = ...) -> None:

Creates 2D Label.

Parameters

• text – label text

• x – label 2D location in screen coords [0..1], corresponding to top left corner of label

• y – label 2D location in screen coords [0..1], corresponding to top left corner of label

• align_right – if True - anchor point of the label is the right side

• align_top – if True - anchor point of the label is the top side

set_position()

def set_position(self, x: float, y: float, z: float) -> None:

Set label position. Position correspnods to top left (viewer’s left) of label.

Args:

x,y,z: label position in 3D

def set_position(self, x: float, y: float, align_right: bool = ...) -> None:

Set position of the 2D label.

Args:

x,y: label 2D position in screen coords [0..1] align_right: if True - anchor point of the label is the right side align_top: if True - anchor point of the label is the top side

set_rgba()

Set the color of the label.

Parameters

rgba – 4 value tuple of RGBA color

set_scale()

Set scaling factor of the label.

Parameters

scale – text scale factor

set_text()

Update label text.

Parameters

text – new text to display

Camera and TargetDisplay

class Camera

Controls the camera view and projection.

dolly()

Move the camera towards or away from the target.

dolly_xy()

Move the camera in the XY plane of the camera view.

Parameters

• x – horizontal offset

• y – vertical offset

pitch()

Pitch the camera up or down.

reset()

Reset the camera view and fov.

set_fov()

Set the diagonal field of view.

set_orthographic()

Use an orthographic or perspective projection.

set_proj_offset()

Set the 2d position of camera target in the viewport.

Parameters

• x – horizontal position in in normalized coordinates [-1, 1]

• y – vertical position in in normalized coordinates [-1, 1]

yaw()

Orbit the camera left or right about the camera target.

class TargetDisplay

Manages the state of the camera target display.

enable_rings()

Enable or disable distance ring display.

set_ring_size()

Set the distance between rings.

Events WindowCtx

class WindowCtx

Context for input callbacks.

property lbutton_down

True if the left mouse button is held

property mbutton_down

True if the middle mouse button is held

property mouse_x

Current mouse x position

property mouse_y

Current mouse y position

property viewport_height

Current viewport height in pixels

property viewport_width

Current viewport width in pixels