how to calibrate lidar l515 and how to use pointcloud in python

[saisatheesh5]

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Required Info
Camera Model	{ L515}
Firmware Version	(Open RealSense Viewer --> 2.50
Operating System & Version	{Linux (Ubuntu 18)
Kernel Version (Linux Only)	(5.4)
Platform	PC
SDK Version	{ legacy / 2.0 }
Language	{python }
Segment	{Robot/Smartphone/VR/AR/others }

Issue Description

Hai, I am using L515 lidar camera. In my case, I need to measure the distance between two points in an object and I need to measure the angle of the bending object. suggest some links to solve my issue. i think I want to use the point cloud to detect the particular pixel point is correct? and how to calibarate my camera to measure the accurate result.

[MartyG-RealSense]

Hi @saisatheesh5 A Python script for measuring the distance between two points is provided at the link below.

https://github.com/soarwing52/RealsensePython/blob/master/separate%20functions/measure_new.py

For measuring the angle of a bending object, a discussion at #9297 about measuring an object's height by calculating its angle from the ground may be a helpful reference.

In regard to calibration, the L515 camera model does not have a calibration tool for its depth and RGB sensors.

[saisatheesh5]

Thank you so much MartyG. How do I get a particular pixel value in an object automatically using the point cloud?

[saisatheesh5]

def calculate_distance(self,x,y):
color_intrin = self.color_intrin
ix,iy = self.ix, self.iy
udist = self.depth_frame.get_distance(ix,iy)
vdist = self.depth_frame.get_distance(x, y)
#print udist,vdist

    point1 = rs.rs2_deproject_pixel_to_point(color_intrin, [ix, iy], udist)
    point2 = rs.rs2_deproject_pixel_to_point(color_intrin, [x, y], vdist)
    #print str(point1)+str(point2)

    dist = math.sqrt(
        math.pow(point1[0] - point2[0], 2) + math.pow(point1[1] - point2[1],2) + math.pow(
            point1[2] - point2[2], 2))
    #print 'distance: '+ str(dist)
    return dist

In this program it will return the distance in mm or inches?

[MartyG-RealSense]

The RealSense SDK's get_distance() instruction returns distance in meters.

https://intelrealsense.github.io/librealsense/doxygen/classrs2_1_1depth__frame.html#a5090d69d04ade6dd67175cae9b6bee9c

[MartyG-RealSense]

Hi @saisatheesh5 Do you require further assistance with this case, please? Thanks!

[MartyG-RealSense]

Thanks very much @saisatheesh5 for the update!