IR Stream in the dark room (white laser dots cleaning)

[DuyguSerbes]

Required Info
Camera Model	D435i
Firmware Version	Open RealSense Viewer
Operating System & Version	Ubuntu 18.04
Kernel Version (Linux Only)	5.4.0-72-generic
Platform	PC
SDK Version	l2.0
Language	Python
Segment	{Robot/Smartphone/VR/AR/others }

Issue Description

Hello all,

I want to get infrared stream in the dark environment conditions. In order to do that I increase laser power but it creates white laser dot on the image. How can I get rid of this kind of issues? When I drop laser power to 0 or 1, the white laser dots dont be visible but rest of image become black.

Do you have any solution to get clean IR stream in the dark room?

[MartyG-RealSense]

Hi @DuyguSerbes You are referring to the bright white dots covered all over the infrared image when the laser is set at maximum power, yes?

Instead of using the camera's built-in projector, you could provide illumination for the camera by using a patternless external IR illuminator in the scene, as described in the link below.

#2000

[DuyguSerbes]

Hello @MartyG-RealSense even if I didn't set a maximum, the bright white dots covers the image. I don't have external illuminator. Is there a any solution for this problem? I want to use infrared images for computer vision so I need clean images.

[MartyG-RealSense]

You could enable the Emitter On-Off option so that the emitter rapidly alternates between on and off on a per-frame basis, and create a script that only captures frames where the emitter status is 'off'.

You can test whether this solution may work for you in the RealSense Viewer. Enable the Emitter On-Off option and on the infrared stream, tap the space bar on the keyboard quickly to pause and unpause the stream. When you manage to pause at a frame where the dot pattern is inactive, check whether the infrared image is still visible when the dot pattern is off.

This pause-unpause technique is demonstrated in the images below.

[DuyguSerbes]

I believe It would work. Is there any available script written in C/C++ or Python to manage Emitter on/off option.

I try to use frames directly in my code. So I should take the frames directly from camera without using realsense-viewer.

[MartyG-RealSense]

There is a Python script that features enabling of the emitter on-off feature in the opening message of the link below.

#6202

The C++ equivalent would be something like:

depth_sensor.set_option(RS2_OPTION_EMITTER_ON_OFF, 1);

[MartyG-RealSense]

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

[MartyG-RealSense]

Case closed due to no further comments received.