/pylon-ros-camera

The official pylon ROS driver for Basler GigE Vision and USB3 Vision cameras:

Primary LanguageC++OtherNOASSERTION

ROS2-Driver for Basler Cameras

The official pylon ROS2 driver for Basler 2D GigE Vision and USB3 Vision cameras

This driver provides many functionalities available through the Basler pylon Camera Software Suite C++ API.

Please Note: This project is offered with no technical support by Basler AG. You are welcome to post any questions or issues on GitHub

Installation

Prerequisites

  • From Ubuntu 20.04 Focal Fossa
  • From ROS2 Galactic Geochelone. Your ROS2 environment must be configured, your workspace created, and colcon, used to build the packages, installed.
  • From pylon Camera Software Suite version 6.2 or newer. The latest APi libraries must be installed manually. Download and install the latest pylon Camera Software Suite Linux Debian Installer Package for your architecture.
  • xterm. The xterm terminal emulator must be installed (refer to the Know Issues section below) as a debian package (sudo apt update && sudo apt install xterm).

Install and build the packages

This repository including the pylon ROS2 packages must be cloned in your workspace (e.g., dev_ws):
For ROS2 Galactic Geochelone: cd ~/dev_ws/src && git clone -b galactic https://github.com/basler/pylon-ros-camera pylon_ros2_camera
Due to a known issue with ROS2 (see the dedicated section below), the latest version of the image_common package must be installed from sources:
For ROS2 Galactic Geochelone: cd ~/dev_ws/src/pylon_ros2_camera && git clone https://github.com/ros-perception/image_common.git -b galactic

Install the ROS2 dependencies required by the pylon ROS2 packages:
cd ~/dev_ws && rosdep install --from-paths src --ignore-src -r -y

Compile the workspace using colcon:
cd ~/dev_ws && colcon build

Note: The --symlink-install flag can be added to the colcon build command. This allows the installed files to be changed by changing the files in the source space (e.g., Python files or other not compiled resourced) for faster iteration (refer to the ROS2 documentation).

Note: The packages are built in Release by default. The build type can be modfied by using the --cmake-args flag (for instance colcon build --symlink-install --cmake-args=-DCMAKE_BUILD_TYPE=Debug).

Source the environment:
cd ~/dev_ws && . install/setup.bash

Note: This step can be skipped if the setup.bash file is sourced in your .bashrc.

Start the driver:
ros2 launch pylon_ros2_camera_wrapper pylon_ros2_camera.launch.py

Usage in a nutshell

Starting the pylon_ros2_camera_node starts the acquisition from a given Basler camera. The nodes allow as well to access many camera parameters and parameters related to the grabbing process itself.

The pylon_ros2_camera_node can be started thanks to a dedicated launch file thanks to the command:
ros2 launch pylon_ros2_camera_wrapper pylon_ros2_camera.launch.py
Several parameters can be set through the launch file and the user parameter file loaded through it (the pylon_ros2_camera_wrapper/config/default.yaml user parameter file is loaded by default).

Acquisition from a specific camera is possible by setting the device_user_id parameter. If no specific camera is specified, the first available camera is connected automatically.

The pylon node defines the different interface names according to the following convention:
[Camera name (= my_camera by default)]/[Node name (= pylon_ros2_camera_node)]/[Interface name]
The camera and the node names can be set thanks respectively to the camera_name and node_name parameters.

Acquisition images are published through the [Camera name]/[Node name]/[image_raw] topic, only if a subscriber to this topic has been registered.
To visualize the images, rqt can be used. Add an image viewer plugin through thanks to the contextual menu (Plugin -> Visualization -> Image View) and select the [Camera name]/[Node name]/[image_raw] topic to display the acquired and published images.

Specific user set can be specified thanks to the startup_user_set parameter.
ros2 launch pylon_ros2_camera_wrapper pylon_ros2_camera.launch.py --ros-args -p startup_user_set:=Default or ros2 launch pylon_ros2_camera_wrapper pylon_ros2_camera.launch.py --ros-args -p startup_user_set:=UserSet1 or ros2 launch pylon_ros2_camera_wrapper pylon_ros2_camera.launch.py --ros-args -p startup_user_set:=UserSet2 or ros2 launch pylon_ros2_camera_wrapper pylon_ros2_camera.launch.py --ros-args -p startup_user_set:=UserSet3

The default trigger mode is set to software trigger. This means that the image acquisition is triggered with a certain frame rate, which may be lower than the maximum camera frame rate. The maximum camera frame rate can be reached when running a camera in a free-run or a hardware trigger mode.

Image pixel encoding

The pylon ROS2 driver support currently the following ROS2 image pixel formats :

* mono8	        (Basler Format : Mono8)
* mono16	(Basler Format : Mono16, Mono12)        (Notes 1&2)
* bgr8 		(Basler Format : BGR8)
* rgb8 		(Basler Format : RGB8)
* bayer_bggr8 	(Basler Format : BayerBG8)
* bayer_gbrg8 	(Basler Format : BayerGB8)
* bayer_rggb8 	(Basler Format : BayerRG8)
* bayer_grbg8 	(Basler Format : BayerRG8)
* bayer_rggb16	(Basler Format : BayerRG16, BayerRG12)  (Notes 1&2)
* bayer_bggr16 	(Basler Format : BayerBG16, BayerBG12)  (Notes 1&2)
* bayer_gbrg16 	(Basler Format : BayerGB16, BayerGB12)  (Notes 1&2)
* bayer_grbg16 	(Basler Format : BayerGR16, BayerGR12)  (Notes 1&2)

NOTES:

1 : 12-bits image will be remapped to 16-bits using bit shifting to make it work with the ROS2 16-bits sensor standard message.

2 : When the user calls the set_image_encoding service to use 16-bits encoding, the driver will check first for the availability of the requested 16-bits encoding to set it, when the requested 16-bits image encoding is not available, then the driver will check the availability of the equivalent 12-bits encoding to set it. When both 16-bits and 12-bits image encoding are not available then an error message will be returned.

Intrinsic calibration and rectified images

ROS2 includes a standardised camera intrinsic calibration process through the camera_calibration package. This calibration process generates a file, which can be processed by the pylon ROS2 driver by setting the camera_info_url parameter in the pylon_ros2_camera_component/config/default.yaml file (it is the user parameter file loaded by default through the driver main launch file) to the correct URI (e.g., file:///home/user/data/calibrations/my_calibration.yaml).

If the calibration is valid, the rectified images are published through the [Camera name]/[Node name]/[image_rect] topic, only if a subscriber to this topic has been registered.

Setting device user id

It is easily possible to connect to a specific camera through its user id. This user id can be set through the parameter device_user_id listed in the .yaml user parameter file loaded at launch time (by default pylon_ros2_camera_component/config/default.yaml). It is up to the user to create specific launch files, loading specific .yaml user parameter files, which would specify the user ids of the cameras that need to be connected. If no specific camera is specified, either because the device_user_id parameter is not set or no .yaml user parameter file is loaded, the first available camera is connected automatically.

In addition to being able to do so through the pylon Viewer provided by Basler, it is possible to set the device user id with the command: ros2 run pylon_ros2_camera_component set_device_user_id [-sn SERIAL_NB] your_device_user_id. If no serial number is specified thanks to the option -sn, the specified device user id your_device_user_id will be assigned to the first available camera. USB cameras must be disconnected and then reconnected after setting a new device user id. USB cameras keep their old user id otherwise.

Packages

  • pylon_ros2_camera_component: the driver itself. The package includes the main pylon_ros2_camera_node developed as a component.
  • pylon_ros2_camera_wrapper: wrapper creating the main component pylon_ros2_camera::PylonROS2CameraNode implemented in the pylon_ros2_camera_component package. The wrapper starts the driver in a single process.
  • pylon_ros2_camera_interfaces: package implementing pylon_ros2_camera_node interfaces (messages, services and actions).

Parameters

Common parameters

  • camera_frame
    The tf2 frame under which the images were published.
    ROS2 provides a library called tf2 (TransForm version 2) to manage the coordinate transformations between the different frames (coordinate systems) defined by the user and assigned to the components of a robotics system.

  • device_user_id
    The DeviceUserID of the camera. If empty, the first camera found in the device list will be used.

  • camera_info_url
    The CameraInfo URL (Uniform Resource Locator) where the optional intrinsic camera calibration parameters are stored. This URL string will be parsed from the CameraInfoManager.

  • image_encoding
    The encoding of the pixels -- channel meaning, ordering, size taken from the list of strings in include file sensor_msgs/image_encodings.h. The supported encodings are 'mono8', 'bgr8', 'rgb8', 'bayer_bggr8', 'bayer_gbrg8' and 'bayer_rggb8'. Default values are 'mono8' and 'rgb8'.

  • binning_x & binning_y
    Binning factor to get downsampled images. It refers here to any camera setting which combines rectangular neighborhoods of pixels into larger "super-pixels." It reduces the resolution of the output image to (width / binning_x) x (height / binning_y). The default values binning_x = binning_y = 0 are considered the same as binning_x = binning_y = 1 (no subsampling).

  • downsampling_factor_exposure_search
    To speed up the exposure search, the mean brightness is not calculated on the entire image, but on a subset instead. The image is downsampled until a desired window hight is reached. The window hight is calculated out of the image height divided by the downsampling_factor_exposure search.

  • frame_rate
    The desired publisher frame rate if listening to the topics. This parameter can only be set once at start-up. Calling the GrabImages-Action can result in a higher frame rate.

  • shutter_mode
    Set mode of camera's shutter if the value is not empty. The supported modes are 'rolling', 'global' and 'global_reset'. Default value is '' (empty)

  • white_balance_auto
    Camera white balance auto.

  • white_balance_ratio_red & white_balance_ratio_green & white_balance_ratio_blue
    Camera white balance ratio.

  • trigger_timeout
    Camera trigger timeout in ms.

  • grab_timeout
    Camera grab timeout in ms.

  • grab_strategy
    Camera grab strategy: 0 = GrabStrategy_OneByOne / 1 = GrabStrategy_LatestImageOnly / 2 = GrabStrategy_LatestImages

Image Intensity Settings

The following settings do NOT have to be set. Each camera has default values which provide an automatic image adjustment resulting in valid images.

  • exposure
    The exposure time in microseconds to be set after opening the camera.

  • gain
    The target gain in percent of the maximal value the camera supports. For USB cameras, the gain is in dB, for GigE cameras it is given in so called 'device specific units'.

  • gamma
    Gamma correction of pixel intensity. Adjusts the brightness of the pixel values output by the camera's sensor to account for a non-linearity in the human perception of brightness or of the display system (such as CRT).

  • brightness
    The average intensity value of the images. It depends the exposure time as well as the gain setting. If 'exposure' is provided, the interface will try to reach the desired brightness by only varying the gain. (What may often fail, because the range of possible exposure values is many times higher than the gain range). If 'gain' is provided, the interface will try to reach the desired brightness by only varying the exposure time. If 'gain' AND 'exposure' are given, it is not possible to reach the brightness, because both are assumed to be fix.

  • brightness_continuous
    Only relevant, if 'brightness' is set: The brightness_continuous flag controls the auto brightness function. If it is set to false, the brightness will only be reached once. Hence changing light conditions lead to changing brightness values. If it is set to true, the given brightness will be reached continuously, trying to adapt to changing light conditions. This is only possible for values in the possible auto range of the pylon API which is e.g., [50 - 205] for acA2500-14um and acA1920-40gm.

  • exposure_auto & gain_auto
    Only relevant, if 'brightness' is set: If the camera should try to reach and / or keep the brightness, hence adapting to changing light conditions, at least one of the following flags must be set. If both are set, the interface will use the profile that tries to keep the gain at minimum to reduce white noise. The exposure_auto flag indicates, that the desired brightness will be reached by adapting the exposure time. The gain_auto flag indicates, that the desired brightness will be reached by adapting the gain.

Optional and device specific parameter

  • exposure_search_timeout
    The timeout while searching the exposure which is connected to the desired brightness. For slow system this has to be increased.

  • auto_exposure_upper_limit
    The exposure search can be limited with an upper bound. This is to prevent very high exposure times and resulting timeouts. A typical value for this upper bound is ~2000000us.

  • gige/mtu_size
    The MTU size. Only used for GigE cameras. To prevent lost frames configure the camera has to be configured with the MTU size the network card supports. A value greater 3000 should be good (1500 for single-board computer)

  • gige/inter_pkg_delay
    The inter-packet delay in ticks. Only used for GigE cameras. To prevent lost frames it should be greater than 0. For most of GigE cameras, a value of 1000 is reasonable. For GigE cameras used on single-board computer, this value should be set to 11772.

  • auto_flash
    Flag that indicates if the camera has a flash connected, which should be on exposure. Only supported for GigE cameras. Default: false.

  • auto_flash_line_2
    Flag that indicates if the camera has a flash connected on line 2, which should be on exposure. Only supported for GigE cameras. Default: true.

  • auto_flash_line_3
    Flag that indicates if the camera has a flash connected on line 3, which should be on exposure. Only supported for GigE cameras. Default: true.

ROS2 pylon node specific parameter

  • startup_user_set
    Flag specifying if a given user set is used when starting the camera.

  • enable_status_publisher
    Flag used to enable/disable the node status publisher.

  • enable_current_params_publisher
    Flag used to enable/disable the current camera publisher.

PTP synchronization

The Precision Time Protocol (PTP) camera feature allows you to synchronize multiple GigE cameras in the same network. It enables a camera to use the following features, if available:

  • Scheduled Action Commands & Action Commands
  • Synchronous Free Run (applies to ace 1 cameras)
  • Periodic Signal (applies to ace 2 cameras)

Refer to the documentation for more info about these features, with multiple code samples.

The pylon driver gives accordingly access through ROS2 services to the following parameters and commands:

ACE 1

PTP configuration & activation

  • GevIEEE1588 -> /my_camera/pylon_ros2_camera_node/enable_ptp [std_srvs/srv/SetBool]

Scheduled Action Commands & Action Commands

  • ActionDeviceKey -> /my_camera/pylon_ros2_camera_node/set_action_trigger_configuration [pylon_ros2_camera_interfaces/srv/SetActionTriggerConfiguration]
  • ActionGroupKey -> /my_camera/pylon_ros2_camera_node/set_action_trigger_configuration [pylon_ros2_camera_interfaces/srv/SetActionTriggerConfiguration]
  • ActionGroupMask -> /my_camera/pylon_ros2_camera_node/set_action_trigger_configuration [pylon_ros2_camera_interfaces/srv/SetActionTriggerConfiguration]
  • IssueScheduledActionCommand -> /my_camera/pylon_ros2_camera_node/issue_scheduled_action_command [pylon_ros2_camera_interfaces/srv/IssueScheduledActionCommand]
  • IssueActionCommand -> /my_camera/pylon_ros2_camera_node/issue_action_command [pylon_ros2_camera_interfaces/srv/IssueActionCommand]

Synchronous Free Run

  • SyncFreeRunTimerStartTimeLow -> /my_camera/pylon_ros2_camera_node/set_sync_free_run_timer_start_time_low [pylon_ros2_camera_interfaces/srv/SetIntegerValue]
  • SyncFreeRunTimerStartTimeHigh -> /my_camera/pylon_ros2_camera_node/set_sync_free_run_timer_start_time_high [pylon_ros2_camera_interfaces/srv/SetIntegerValue]
  • SyncFreeRunTimerTriggerRateAbs -> /my_camera/pylon_ros2_camera_node/set_sync_free_run_timer_trigger_rate_abs [pylon_ros2_camera_interfaces/srv/SetFloatValue]
  • SyncFreeRunTimerUpdate -> /my_camera/pylon_ros2_camera_node/update_sync_free_run_timer [std_srvs/srv/Trigger]
  • SyncFreeRunTimerEnable -> //my_camera/pylon_ros2_camera_node/enable_sync_free_run_timer [std_srvs/srv/SetBool]

ACE 2

PTP configuration & activation

  • BslPtpPriority1 -> /my_camera/pylon_ros2_camera_node/set_ptp_priority [pylon_ros2_camera_interfaces/srv/SetIntegerValue]
  • BslPtpProfile -> /my_camera/pylon_ros2_camera_node/set_ptp_profile [pylon_ros2_camera_interfaces/srv/SetIntegerValue]
  • BslPtpNetworkMode -> /my_camera/pylon_ros2_camera_node/set_ptp_network_mode [pylon_ros2_camera_interfaces/srv/SetIntegerValue]
  • BslPtpUcPortAddrIndex -> /my_camera/pylon_ros2_camera_node/set_ptp_uc_port_address_index [pylon_ros2_camera_interfaces/srv/SetIntegerValue]
  • BslPtpUcPortAddr -> /my_camera/pylon_ros2_camera_node/set_ptp_uc_port_address [pylon_ros2_camera_interfaces/srv/SetIntegerValue]
  • BslPtpManagementEnable -> /my_camera/pylon_ros2_camera_node/enable_ptp_management_protocol [std_srvs/srv/SetBool]
  • BslTwoStep -> /my_camera/pylon_ros2_camera_node/enable_two_step_operation [std_srvs/srv/SetBool]
  • PtpEnable -> /my_camera/pylon_ros2_camera_node/enable_ptp [std_srvs/srv/SetBool]

Scheduled Action Commands & Action Commands

  • ActionDeviceKey -> /my_camera/pylon_ros2_camera_node/set_action_trigger_configuration [pylon_ros2_camera_interfaces/srv/SetActionTriggerConfiguration]
  • ActionGroupKey -> /my_camera/pylon_ros2_camera_node/set_action_trigger_configuration [pylon_ros2_camera_interfaces/srv/SetActionTriggerConfiguration]
  • ActionGroupMask -> /my_camera/pylon_ros2_camera_node/set_action_trigger_configuration [pylon_ros2_camera_interfaces/srv/SetActionTriggerConfiguration]
  • IssueScheduledActionCommand -> /my_camera/pylon_ros2_camera_node/issue_scheduled_action_command [pylon_ros2_camera_interfaces/srv/IssueScheduledActionCommand]
  • IssueActionCommand -> /my_camera/pylon_ros2_camera_node/issue_action_command [pylon_ros2_camera_interfaces/srv/IssueActionCommand]

Periodic Signal

  • BslPeriodicSignalDelay -> /my_camera/pylon_ros2_camera_node/set_periodic_signal_delay [pylon_ros2_camera_interfaces/srv/SetFloatValue]
  • BslPeriodicSignalPeriod -> /my_camera/pylon_ros2_camera_node/set_periodic_signal_period [pylon_ros2_camera_interfaces/srv/SetFloatValue]

Publishers

Name Notes
/my_camera/pylon_ros2_camera_node/camera_info sensor_msgs/msg/CameraInfo
/my_camera/pylon_ros2_camera_node/current_params current camera parameter
/my_camera/pylon_ros2_camera_node/image_raw acquired images
/my_camera/pylon_ros2_camera_node/image_rect rectified images if the camera is calibrated
/my_camera/pylon_ros2_camera_node/status camera status

Service servers

Name Notes
/my_camera/pylon_ros2_camera_node/activate_autoflash_output_[index] data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/describe_parameters -
/my_camera/pylon_ros2_camera_node/enable_ptp data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/enable_ptp_management_protocol data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/enable_sync_free_run_timer data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/enable_two_step_operation data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/execute_software_trigger -
/my_camera/pylon_ros2_camera_node/get_chunk_counter_value -
/my_camera/pylon_ros2_camera_node/get_chunk_enable -
/my_camera/pylon_ros2_camera_node/get_chunk_exposure_time -
/my_camera/pylon_ros2_camera_node/get_chunk_frame_counter -
/my_camera/pylon_ros2_camera_node/get_chunk_line_status_all -
/my_camera/pylon_ros2_camera_node/get_chunk_mode_active -
/my_camera/pylon_ros2_camera_node/get_chunk_selector -
/my_camera/pylon_ros2_camera_node/get_chunk_timestamp -
/my_camera/pylon_ros2_camera_node/get_max_num_buffer -
/my_camera/pylon_ros2_camera_node/get_parameter_types -
/my_camera/pylon_ros2_camera_node/get_parameters -
/my_camera/pylon_ros2_camera_node/get_statistic_buffer_underrun_count -
/my_camera/pylon_ros2_camera_node/get_statistic_failed_buffer_count -
/my_camera/pylon_ros2_camera_node/get_statistic_failed_packet_count -
/my_camera/pylon_ros2_camera_node/get_statistic_missed_frame_count -
/my_camera/pylon_ros2_camera_node/get_statistic_resend_request_count -
/my_camera/pylon_ros2_camera_node/get_statistic_resynchronization_count -
/my_camera/pylon_ros2_camera_node/get_statistic_total_buffer_count -
/my_camera/pylon_ros2_camera_node/issue_action_command -
/my_camera/pylon_ros2_camera_node/issue_scheduled_action_command -
/my_camera/pylon_ros2_camera_node/list_parameters -
/my_camera/pylon_ros2_camera_node/load_user_set -
/my_camera/pylon_ros2_camera_node/reset_device -
/my_camera/pylon_ros2_camera_node/save_user_set -
/my_camera/pylon_ros2_camera_node/set_PGI_mode data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/set_acquisition_frame_count value = new targeted frame count
/my_camera/pylon_ros2_camera_node/set_action_trigger_configuration -
/my_camera/pylon_ros2_camera_node/set_binning -
/my_camera/pylon_ros2_camera_node/set_black_level value = new targeted black level
/my_camera/pylon_ros2_camera_node/set_brightness -
/my_camera/pylon_ros2_camera_node/set_chunk_enable data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/set_chunk_exposure_time -
/my_camera/pylon_ros2_camera_node/set_chunk_mode_active data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/set_chunk_selector -
/my_camera/pylon_ros2_camera_node/set_demosaicing_mode value : 0 = Simple, 1 = Basler PGI
/my_camera/pylon_ros2_camera_node/set_device_link_throughput_limit value = new targeted throughput limit in Bytes/sec.
/my_camera/pylon_ros2_camera_node/set_device_link_throughput_limit_mode data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/set_exposure -
/my_camera/pylon_ros2_camera_node/set_gain -
/my_camera/pylon_ros2_camera_node/set_gamma value: 0 = User, 1 = sRGB
/my_camera/pylon_ros2_camera_node/set_gamma_activation (For GigE Cameras)
/my_camera/pylon_ros2_camera_node/set_gamma_selector value : 0 = User, 1 = sRGB (For GigE Cameras)
/my_camera/pylon_ros2_camera_node/set_grab_timeout -
/my_camera/pylon_ros2_camera_node/set_grabbing_strategy -
/my_camera/pylon_ros2_camera_node/set_image_encoding value = mono8, mono16, bgr8, rgb8, bayer_bggr8, bayer_gbrg8, bayer_rggb8, bayer_grbg8, bayer_rggb16, bayer_bggr16, bayer_gbrg16, bayer_grbg16
/my_camera/pylon_ros2_camera_node/set_light_source_preset value : 0 = Off, 1 = Daylight5000K, 2 = Daylight6500K, 3 = Tungsten2800K
/my_camera/pylon_ros2_camera_node/set_line_debouncer_time value = delay in micro sec.
/my_camera/pylon_ros2_camera_node/set_line_inverter data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/set_line_mode value : 0 = Input, 1 = Output
/my_camera/pylon_ros2_camera_node/set_line_selector value : 0 = Line1, 1 = Line2, 2 = Line3, 3 = Line4
/my_camera/pylon_ros2_camera_node/set_line_source value : 0 = Exposure Active, 1 = FrameTriggerWait, 2 = UserOutput1, 3 = Timer1Active, 4 = FlashWindow
/my_camera/pylon_ros2_camera_node/set_max_num_buffer -
/my_camera/pylon_ros2_camera_node/set_max_transfer_size maximum USB data transfer size in bytes
/my_camera/pylon_ros2_camera_node/set_noise_reduction value = reduction value
/my_camera/pylon_ros2_camera_node/set_offset_x value = targeted offset in x-axis
/my_camera/pylon_ros2_camera_node/set_offset_y value = targeted offset in y-axis
/my_camera/pylon_ros2_camera_node/set_output_queue_size -
/my_camera/pylon_ros2_camera_node/set_parameters -
/my_camera/pylon_ros2_camera_node/set_parameters_atomically -
/my_camera/pylon_ros2_camera_node/set_periodic_signal_delay value : delay to be applied to the periodic signal in microseconds
/my_camera/pylon_ros2_camera_node/set_periodic_signal_period value : length of the periodic signal in microseconds
/my_camera/pylon_ros2_camera_node/set_ptp_network_mode value : 1 = Hybrid, 2 = Multicast, 3 = Unicast
/my_camera/pylon_ros2_camera_node/set_ptp_priority value = value indicating the priority of the device when determining the master clock
/my_camera/pylon_ros2_camera_node/set_ptp_profile value : 1 = Delay Request Response Default Profile, 2 = Peer to Peer Default Profile
/my_camera/pylon_ros2_camera_node/set_ptp_uc_port_address value = unicast port address
/my_camera/pylon_ros2_camera_node/set_ptp_uc_port_address_index value = unicast port address index
/my_camera/pylon_ros2_camera_node/set_reverse_x data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/set_reverse_y data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/set_roi -
/my_camera/pylon_ros2_camera_node/set_sensor_readout_mode value : 0 = Normal, 1 = Fast
/my_camera/pylon_ros2_camera_node/set_sharpness_enhancement value = sharpness value
/my_camera/pylon_ros2_camera_node/set_sleeping -
/my_camera/pylon_ros2_camera_node/set_sync_free_run_timer_start_time_high value = high 32 bits of the synchronous free run trigger start time
/my_camera/pylon_ros2_camera_node/set_sync_free_run_timer_start_time_low value = low 32 bits of the synchronous free run trigger start time
/my_camera/pylon_ros2_camera_node/set_sync_free_run_timer_trigger_rate_abs value = synchronous free run trigger rate
/my_camera/pylon_ros2_camera_node/set_timer_duration value = duration of the currently selected timer in microseconds
/my_camera/pylon_ros2_camera_node/set_timer_selector value : 1 = Timer 1, 2 = Timer 2, 3 = Timer 3, 4 = Timer 4
/my_camera/pylon_ros2_camera_node/set_timer_trigger_source value = see valid values of TimerTriggerSourceEnums in documentation
/my_camera/pylon_ros2_camera_node/set_trigger_activation value : 0 = RigingEdge, 1 = FallingEdge
/my_camera/pylon_ros2_camera_node/set_trigger_delay value = delay in micro sec.
/my_camera/pylon_ros2_camera_node/set_trigger_mode data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/set_trigger_selector value : 0 = Frame start, 1 = Frame burst start (ace USB cameras) / Acquisition Start (ace GigE cameras)
/my_camera/pylon_ros2_camera_node/set_trigger_source value : 0 = Software, 1 = Line 1, 2 = Line 3, 3 = Line 4, 4 = Action 1, 5 = Periodic Signal 1
/my_camera/pylon_ros2_camera_node/set_trigger_timeout -
/my_camera/pylon_ros2_camera_node/set_user_output_[index] data : false = deactivate, true = activate
/my_camera/pylon_ros2_camera_node/set_user_set_default_selector value : 0 = Default, 1 = UserSet1, 2 = UserSet2, 3 = UserSet3, 4 = HighGain, 5 = AutoFunctions, 6 = ColorRaw
/my_camera/pylon_ros2_camera_node/set_user_set_selector value : 0 = Default, 1 = UserSet1, 2 = UserSet2, 3 = UserSet3, 4 = HighGain, 5 = AutoFunctions, 6 = ColorRaw
/my_camera/pylon_ros2_camera_node/set_white_balance -
/my_camera/pylon_ros2_camera_node/set_white_balance_auto value : 0 = Off, 1 = Once, 2 = Continuous
/my_camera/pylon_ros2_camera_node/start_grabbing -
/my_camera/pylon_ros2_camera_node/stop_grabbing -
/my_camera/pylon_ros2_camera_node/update_sync_free_run_timer -
/my_camera/set_camera_info -

Action servers

Name Notes
/my_camera/pylon_ros2_camera_node/grab_images_raw -

Through this action, it is possible to grab one image or a sequence of images with user-specified parameters (e.g., exposure time, brightness value, etc.). Refer to the action definition to get more information.

The camera-characteristic parameter such as height, width, projection matrix (by ROS2 convention, this matrix specifies the intrinsic (camera) matrix of the processed (rectified) image - see the CameraInfo message definition for detailed information) and camera_frame were published over the /camera_info topic. Furthermore, an action-based image grabbing with desired exposure time, gain, gamma and / or brightness is provided. Hence, one can grab a sequence of images with above target settings as well as a single image. Grabbing images through this action can result in a higher frame rate.

Known issues

Getting the number of subscribers from camera publisher

It is not possible to count correctly the number of subscribers to the image_raw and image_rect topics because of a known issue with the function CameraPublisher::getNumSubscribers. That is why this image_common package, fixing this issue, needs to be cloned and compiled together with the pylon_ros2_camera_node.

User input in terminal when starting node through launch files

The ros2 launch mechanism doesn't allow to access stdin through a terminal (see here and here). This is solved in this implementation by installing and using xterm to emulate a terminal with possible user interaction.

Service shutdown

In the ROS pylon implementation, the activate_autoflash_output and set_user_output service servers are shutdowned when the connection with a camera is lost. It is not possible for now to do so with ROS2 without shutting down the whole node (see here). There is no way to overcome this issue at the moment.

Troubleshooting

To increase performance and to minimize CPU usage when grabbing images, the following settings should be considered:

Camera hot-swapping

If you hot-swap the camera with a different camera with a non-compatible pixel encoding format (e.g., mono and color cameras), you need to restart the ROS system to replace the encoding value or replace the rosparam directly by setting the image_encoding parameter. e.g.,: rosparam set /pylon_camera_node/image_encoding "mono8"

GigE Devices

No connection with connected camera

To be sure to be able to connect to a specific camera, its network configuration must be manually set through Basler's pylon IP configurator. To do so, click on the camera in the list of connected devices, select the Static IP option, set an IP Address within the same range as the one of your computer, and set the same Subnet Mask as the one from your computer.

Maximum UDP Socket Buffer Size

The system's maximum UDP receive buffer size should be increased to ensure a stable image acquisition. A maximum size of 2 MB is recommended. This can be achieved by issuing the sudo sysctl net.core.rmem_max=2097152 command. To make this setting persistent, you can add the net.core.rmem_max setting to the /etc/sysctl.conf file.

Enable Jumbo Frames.

Many GigE network adapters support so-called jumbo frames, i.e., network packets larger than the usual 1500 bytes. To enable jumbo frames, the maximum transfer unit (MTU) size of the PC's network adapter must be set to a high value. We recommend using a value of 8192.

Increase the packet size.

If your network adapter supports jumbo frames, you set the adapter's MTU to 8192 as described above. In order to take advantage of the adapter's jumbo frame capability, you must also set the packet size used by the camera to 8192.

If you are working with the pylon Viewer application, you can set the packet size by first selecting a camera from the tree in the "Device" pane. In the "Features" pane, expand the features group that shows the camera's name, expand the "Transport Layer" parameters group, and set the "Packet Size" parameter to 8192. If you write your own application, use the camera API to set the PacketSize parameter to 8192.

It is possible to change the packet size by changing the default value of the mtu_size parameter in the pylon ROS2 wrapper launch file. When the camera is grabbing, it is not possible to modify this parameter.

Real-time Priority

The GigE Vision implementation of Basler pylon software uses a thread for receiving image data. Basler pylon tries to set the thread priority for the receive thread to real-time thread priority. This requires certain permissions. The 'Permissions for Real-time Thread Priorities' section of the pylon INSTALL document describes how to grant the required permissions.

U3V Devices

Increasing Packet Size

For faster USB transfers you should increase the packet size. You can do this by changing the "Stream Parameters" -> "Maximum Transfer Size" value from inside the pylon Viewer or by setting the corresponding value via the API. After increasing the package size you will likely run out of kernel space and see corresponding error messages on the console. The default value set by the kernel is 16 MB. To set the value (in this example to 1000 MB) you can execute as root: echo 1000 > /sys/module/usbcore/parameters/usbfs_memory_mb This would assign a maximum of 1000 MB to the USB stack.