There are several examples codes for users learn how to use LiDARs. Here is a brief introduction to each sample code:
| Level | Sample | Description |
|---|---|---|
| lidar | lidar_quick_start | Use the SDK interface to quickly obtain LiDAR point cloud data and save it to a PLY file when triggered by user input. |
| lidar | lidar_stream | This sample demonstrates how to configure and start LiDAR and IMU sensor streams, process the data frames through a callback function, and display sensor information. |
| lidar | lidar_device_control | This sample demonstrates how to interactively control LiDAR device properties through a command-line interface, allowing users to get and set various device parameters. |
| lidar | lidar_record | This sample demonstrates how to record LiDAR and IMU sensor data to a bag file format, providing real-time data capture with pause/resume functionality for flexible recording sessions. |
| lidar | lidar_playback | This sample demonstrates how to play back recorded LiDAR and IMU sensor data from bag files, providing full control over playback including pause/resume functionality and automatic replay capabilities. |
The listed examples at previous section are written in C++ language. Here is a brief introduction to c language examples:
| Level | Sample | Description |
|---|---|---|
| lidar | c_lidar_quick_start | This C language sample demonstrates how to quickly obtain LiDAR point cloud data using the SDK C API and save it to a PLY file when triggered by user input. |
| lidar | c_lidar_stream | This C language sample demonstrates how to configure and stream LiDAR and IMU sensor data using the SDK C API, providing interactive sensor selection and real-time data monitoring. |
utils
It contains functions to wait for a key press with an optional timeout, get the current time in milliseconds, and parse the input option from a key press event.This is done with C++.
utils_c
It contains functions to get the current system timestamp and wait for keystrokes from the user, as well as a macro to check for and handle errors. These capabilities can be used in scenarios such as time measurement, user interaction, and error handling. This is done with C.
When using the SDK, if an error occurs, the SDK reports the error by throwing an exception of type ob::Error. The ob::Error exception class typically contains detailed information about the error, which can help developers diagnose the problem. The example uses a ‘try’ block to wrap the entire main function. If an exception of type ob::Error is thrown, the program will catch it and print the error message to the console. Here is the information that can be obtained from an ob::Error:
Function Name (getFunction()): Indicates the name of the function where the exception was thrown. This helps pinpoint the location of the error within the code.
Arguments (getArgs()): Provides information about the arguments passed to the function when the exception occurred. This context can be useful for understanding the specific conditions under which the error happened.
Error Message (what()): Returns a string describing the nature of the error. This is often the most important piece of information, as it directly explains what went wrong.
Exception Type (getExceptionType()): Specifies the type of the exception. This can help categorize the error and determine appropriate handling strategies. Read the comments of the OBExceptionType enum in the libobsensor/h/ObTypes.h file for more information.
Example Code in C++
catch(ob::Error &e) {
std::cerr << "function: " << e.getFunction() << std::endl;
std::cerr << "args: " << e.getArgs() << std::endl;
std::cerr << "message: " << e.what() << std::endl;
std::cerr << "type: " << e.getExceptionType() << std::endl;
exit(EXIT_FAILURE);
}