Camera

Overview

The camera sensor provides image data from customizable perspectives and resolutions. It functions similar to its real-life analogue: the video camera. Users can attach multiple cameras at arbitrary locations to vehicles or the scene. Besides color information, these simulated cameras can be configured to also provide semantic annotation and depth information.

The sensor is available to use from Python API , via the sensors configuration tools and with the Lua console , for which the commands are noted hereafter.

Usage

Camera sensors are exposed to Lua through the sensors extension in the tech folder. Using this API, a Camera sensor can be created with various desired properties, and either attached to a vehicle or to a fixed point on the map.

We can create the Camera either with shared memory or without, using either of the following commands:

sensorId = extensions.tech_sensors.createCamera(vehicleId, args)

sensorId = extensions.tech_sensors.createCameraWithSharedMemory(vehicleId, args)

Args:

vehicleID(int): The vehicle ID. This can be nil (i.e., 0) if the Camera is not to be attached to any vehicle; this also needs isStatic=true.

The args parameter is a Lua table containing as many of the following properties as required. If any property is not set manually then a default value is used, so it is entirely possible to create the Camera with args being an empty table. What follows is a complete list of these arguments:

updateTime(float): How often the Camera sensor should update its readings in the simulator (in seconds). Default value is 0.05.
updatePriority(float): A scheduling priority value for this Camera sensor, in range 0 to 1. 0 is highest priority, 1 is least. Default value is 0.0.
pos(Point3F): The position of the Camera sensor either in vehicle space (if attached to vehicle) or in world space (if fixed to the map).
dir(Point3F): The forward direction in which the Camera sensor points.
up(Point3F): The up direction of the Camera sensor.
fovY(float): The vertical field of view of the Camera sensor, in degrees. Default value is 70.0.
nearFarPlanes(table): The near and far plane distances of the Camera sensor, in metres. * s are {0.05, 100.0}.
renderColours(bool): A flag which indicates if colour data should be rendered with this camera, or not. Default value is true.
renderAnnotation(bool): A flag which indicates if ‘class’ semantic annotation data should be rendered with this camera, or not. Default value is true.
renderInstance(bool): A flag which indicates if ‘instance’ semantic annotation data should be rendered with this camera, or not. Default value is true.
renderDepth(bool): A flag which indicates if depth data should be rendered with this camera, or not. Default value is true.
isVisualised(bool): A flag which indicates if the camera sensor should be visualised. Default value is true.
is_streaming (bool): A flag which indicates whether or not to stream the data directly to shared memory (no poll required, for efficiency).
isStatic(bool): True if the camera sensor is fixed to a point on the map, false if it is attached to a vehicle. Default value is false.
isSnappingDesired(bool): True if the camera sensor position should be forced onto the surface of the vehicle, at its closest vehicle point. This is useful if finding it hard to have the camera sensor on the vehicle itself. False, otherwise, eg if the camera sensor should be suspended at a fixed point relative to the vehicle. Default value is true.
isForceInsideTriangle(bool): Used with isSnappingDesired. True, if the camera sensor should be forced to be inside its nearest vehicle triangle, otherwise false. Default value is true.
postprocess_depth (bool): If True, the raw depth data will be postprocessed to better represent values with middle intensity. Defaults to False, as the postprocessing is computationally intensive.
is_dir_world_space (bool): Flag which indicates if the direction is provided in world-space coordinates (True), or the default vehicle space (False).
integer_depth (bool): If True, depth values will be quantized to the integer range 0-255. If False, depth values will be sent as 32-bit floats in the range of 0.0-1.0. Will be set to False is postprocess_depth=True as full precision is needed for postprocessing. Default value is true.

Returns: sensorId(int): The unique Id number of this sensor, in order to refer to it later, e.g., when closing it.

sensorPosition = extensions.tech_sensors.getCameraSensorPosition(sensorId)

Args: