Public Member Functions | Private Types | Private Member Functions | Private Attributes | List of all members
camera_info_manager::CameraInfoManager Class Reference

CameraInfo Manager class. More...

#include <camera_info_manager.h>

Public Member Functions

 CameraInfoManager (ros::NodeHandle nh, const std::string &cname="camera", const std::string &url="")
 
sensor_msgs::CameraInfo getCameraInfo (void)
 
bool isCalibrated (void)
 
bool loadCameraInfo (const std::string &url)
 
std::string resolveURL (const std::string &url, const std::string &cname)
 
bool setCameraInfo (const sensor_msgs::CameraInfo &camera_info)
 
bool setCameraName (const std::string &cname)
 
bool validateURL (const std::string &url)
 

Private Types

enum  url_type_t {
  URL_empty = 0, URL_file, URL_package, URL_invalid,
  URL_flash
}
 

Private Member Functions

std::string getPackageFileName (const std::string &url)
 
bool loadCalibration (const std::string &url, const std::string &cname)
 
bool loadCalibrationFile (const std::string &filename, const std::string &cname)
 
url_type_t parseURL (const std::string &url)
 
bool saveCalibration (const sensor_msgs::CameraInfo &new_info, const std::string &url, const std::string &cname)
 
bool saveCalibrationFile (const sensor_msgs::CameraInfo &new_info, const std::string &filename, const std::string &cname)
 
bool setCameraInfoService (sensor_msgs::SetCameraInfo::Request &req, sensor_msgs::SetCameraInfo::Response &rsp)
 

Private Attributes

sensor_msgs::CameraInfo cam_info_
 current CameraInfo More...
 
std::string camera_name_
 camera name More...
 
ros::ServiceServer info_service_
 set_camera_info service More...
 
bool loaded_cam_info_
 cam_info_ load attempted More...
 
boost::mutex mutex_
 mutual exclusion lock for private data More...
 
ros::NodeHandle nh_
 node handle for service More...
 
std::string url_
 URL for calibration data. More...
 

Detailed Description

CameraInfo Manager class.

Provides CameraInfo, handles the sensor_msgs/SetCameraInfo service requests, saves and restores sensor_msgs/CameraInfo data.

ROS Service

Typically, these service requests are made by a calibration package, such as:

The calling node must invoke ros::spin() or ros::spinOnce() in some thread, so CameraInfoManager can handle arriving service requests.

Camera Name

The device driver sets a camera name via the CameraInfoManager::CameraInfoManager constructor or the setCameraName() method. This name is written when CameraInfo is saved, and checked when data are loaded, with a warning logged if the name read does not match.

Syntax: a camera name contains any combination of alphabetic, numeric and '_' characters. Case is significant.

Camera drivers may use any syntactically valid name they please. Where possible, it is best for the name to be unique to the device, such as a GUID, or the make, model and serial number. Any parameters that affect calibration, such as resolution, focus, zoom, etc., may also be included in the name, uniquely identifying each CameraInfo file.

Beginning with Electric Emys, the camera name can be resolved as part of the URL, allowing direct access to device-specific calibration information.

Uniform Resource Locator

The location for getting and saving calibration data is expressed by Uniform Resource Locator. The driver defines a URL via the CameraInfoManager::CameraInfoManager constructor or the loadCameraInfo() method. Many drivers provide a ~camera_info_url parameter so users may customize this URL, but that is handled outside this class.

Typically, cameras store calibration information in a file, which can be in any format supported by camera_calibration_parsers. Currently, that includes YAML and Videre INI files, identified by their .yaml or .ini extensions as shown in the examples. These file formats are described here:

Example URL syntax:

The file: URL specifies a full path name in the local system. The package: URL is handled the same as file:, except the path name is resolved relative to the location of the named ROS package, which must be reachable via $ROS_PACKAGE_PATH.

Beginning with Electric Emys, the URL may contain substitution variables delimited by ${...}, including:

Resolution is done in a single pass through the URL string. Variable values containing substitutable strings are not resolved recursively. Unrecognized variable names are treated literally with no substitution, but an error is logged.

Examples with variable substitution:

In C-turtle and Diamondback, if the URL was empty, no calibration data were loaded, and any data provided via set_camera_info would be stored in:

Beginning in Electric, the default URL changed to:

If that file exists, its contents are used. Any new calibration will be stored there, missing parent directories being created if necessary and possible.

Loading Calibration Data

Prior to Fuerte, calibration information was loaded in the constructor, and again each time the URL or camera name was updated. This frequently caused logging of confusing and misleading error messages.

Beginning in Fuerte, camera_info_manager loads nothing until the loadCameraInfo(), isCalibrated() or getCameraInfo() method is called. That suppresses bogus error messages, but allows (valid) load errors to occur during the first getCameraInfo(), or isCalibrated(). To avoid that, do an explicit loadCameraInfo() first.

Definition at line 174 of file camera_info_manager.h.

Member Enumeration Documentation

Enumerator
URL_empty 
URL_file 
URL_package 
URL_invalid 
URL_flash 

Definition at line 194 of file camera_info_manager.h.

Constructor & Destructor Documentation

camera_info_manager::CameraInfoManager::CameraInfoManager ( ros::NodeHandle  nh,
const std::string &  cname = "camera",
const std::string &  url = "" 
)

Constructor

Parameters
nhnode handle, normally for the driver's streaming name space ("camera"). The service name is relative to this handle. Nodes supporting multiple cameras may use subordinate names, like "left/camera" and "right/camera".
cnamedefault camera name
urldefault Uniform Resource Locator for loading and saving data.

Definition at line 78 of file camera_info_manager.cpp.

Member Function Documentation

sensor_msgs::CameraInfo camera_info_manager::CameraInfoManager::getCameraInfo ( void  )

Get the current CameraInfo data.

If CameraInfo has not yet been loaded, an attempt must be made here. To avoid that, ensure that loadCameraInfo() ran previously. If the load is attempted but fails, an empty CameraInfo will be supplied.

The matrices are all zeros if no calibration is available. The image pipeline handles that as uncalibrated data.

Warning
The caller must fill in the message Header of the CameraInfo returned. The time stamp and frame_id should normally be the same as the corresponding Image message Header fields.

Definition at line 106 of file camera_info_manager.cpp.

std::string camera_info_manager::CameraInfoManager::getPackageFileName ( const std::string &  url)
private

Get file name corresponding to a package: URL.

Parameters
urla copy of the Uniform Resource Locator
Returns
file name if package found, "" otherwise

Definition at line 140 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::isCalibrated ( void  )

Is the current CameraInfo calibrated?

If CameraInfo has not yet been loaded, an attempt must be made here. To avoid that, ensure that loadCameraInfo() ran previously. If the load failed, CameraInfo will be empty and this predicate will return false.

Returns
true if the current CameraInfo is calibrated.

Definition at line 173 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::loadCalibration ( const std::string &  url,
const std::string &  cname 
)
private

Load CameraInfo calibration data (if any).

Precondition
mutex_ unlocked
Parameters
urla copy of the Uniform Resource Locator
cnameis a copy of the camera_name_
Returns
true if URL contains calibration data.

sets cam_info_, if successful

Definition at line 210 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::loadCalibrationFile ( const std::string &  filename,
const std::string &  cname 
)
private

Load CameraInfo calibration data from a file.

Precondition
mutex_ unlocked
Parameters
filenamecontaining CameraInfo to read
cnameis a copy of the camera_name_
Returns
true if URL contains calibration data.

Sets cam_info_, if successful

Definition at line 268 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::loadCameraInfo ( const std::string &  url)

Set a new URL and load its calibration data (if any).

If multiple threads call this method simultaneously with different URLs, there is no guarantee which will prevail.

Parameters
urlnew Uniform Resource Locator for CameraInfo.
Returns
true if new URL contains calibration data.
Postcondition
loaded_cam_info_ true (meaning a load was attempted, even if it failed); cam_info_ updated, if successful.

Definition at line 310 of file camera_info_manager.cpp.

CameraInfoManager::url_type_t camera_info_manager::CameraInfoManager::parseURL ( const std::string &  url)
private

Parse calibration Uniform Resource Locator.

Parameters
urlstring to parse
Returns
URL type
Note
Recognized but unsupported URL types have enum values >= URL_invalid.

Definition at line 407 of file camera_info_manager.cpp.

std::string camera_info_manager::CameraInfoManager::resolveURL ( const std::string &  url,
const std::string &  cname 
)

Resolve Uniform Resource Locator string.

Parameters
urla copy of the Uniform Resource Locator, which may include ${...} substitution variables.
cnameis a copy of the camera_name_
Returns
a copy of the URL with any variable information resolved.

Definition at line 333 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::saveCalibration ( const sensor_msgs::CameraInfo &  new_info,
const std::string &  url,
const std::string &  cname 
)
private

Save CameraInfo calibration data.

Precondition
mutex_ unlocked
Parameters
new_infocontains CameraInfo to save
urlis a copy of the URL storage location (if empty, use file://${ROS_HOME}/camera_info/${NAME}.yaml)
cnameis a copy of the camera_name_
Returns
true, if successful

Definition at line 443 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::saveCalibrationFile ( const sensor_msgs::CameraInfo &  new_info,
const std::string &  filename,
const std::string &  cname 
)
private

Save CameraInfo calibration data to a file.

Precondition
mutex_ unlocked
Parameters
new_infocontains CameraInfo to save
filenameis local file to store data
cnameis a copy of the camera_name_
Returns
true, if successful

Definition at line 493 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::setCameraInfo ( const sensor_msgs::CameraInfo &  camera_info)

Set the camera info manually

Parameters
camera_infonew camera calibration data
Returns
true if new camera info is set
Postcondition
cam_info_ updated, if valid;

Definition at line 630 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::setCameraInfoService ( sensor_msgs::SetCameraInfo::Request &  req,
sensor_msgs::SetCameraInfo::Response &  rsp 
)
private

Callback for SetCameraInfo request.

Always updates cam_info_ class variable, even if save fails.

Parameters
reqSetCameraInfo request message
rspSetCameraInfo response message
Returns
true if message handled

Definition at line 558 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::setCameraName ( const std::string &  cname)

Set a new camera name.

Parameters
cnamenew camera name to use for saving calibration data
Returns
true if new name has valid syntax; valid names contain only alphabetic, numeric, or '_' characters.
Postcondition
cam_name_ updated, if valid; since it may affect the URL, cam_info_ will be reloaded before being used again.

Definition at line 597 of file camera_info_manager.cpp.

bool camera_info_manager::CameraInfoManager::validateURL ( const std::string &  url)

Validate URL syntax.

Parameters
urlUniform Resource Locator to check
Returns
true if URL syntax is supported by CameraInfoManager (although the resource need not actually exist)

Definition at line 647 of file camera_info_manager.cpp.

Member Data Documentation

sensor_msgs::CameraInfo camera_info_manager::CameraInfoManager::cam_info_
private

current CameraInfo

Definition at line 236 of file camera_info_manager.h.

std::string camera_info_manager::CameraInfoManager::camera_name_
private

camera name

Definition at line 234 of file camera_info_manager.h.

ros::ServiceServer camera_info_manager::CameraInfoManager::info_service_
private

set_camera_info service

Definition at line 233 of file camera_info_manager.h.

bool camera_info_manager::CameraInfoManager::loaded_cam_info_
private

cam_info_ load attempted

Definition at line 237 of file camera_info_manager.h.

boost::mutex camera_info_manager::CameraInfoManager::mutex_
private

mutual exclusion lock for private data

This non-recursive mutex is only held for a short time while accessing or changing private class variables. To avoid deadlocks and contention, it is never held during I/O or while invoking a callback. Most private methods operate on copies of class variables, keeping the mutex hold time short.

Definition at line 229 of file camera_info_manager.h.

ros::NodeHandle camera_info_manager::CameraInfoManager::nh_
private

node handle for service

Definition at line 232 of file camera_info_manager.h.

std::string camera_info_manager::CameraInfoManager::url_
private

URL for calibration data.

Definition at line 235 of file camera_info_manager.h.


The documentation for this class was generated from the following files:


camera_info_manager
Author(s): Jack O'Quin
autogenerated on Mon Jun 10 2019 13:32:04