Some matching errors from the depth of D435 for outdoor use

[alin45]

hi

we found that D435 works well outdoor most of the time, but some errors as（like the black region）：

but we also found that D435 can calculate the depth for the bad region for holding a while.

so we don't know why the depth will change from the same view.

[MartyG]

The 400 Series cameras have a new advanced chip called the Vision Processor D4. It is possible that the D4 is using its algorithms to improve image quality.

"The Intel® RealSense™ Vision Processor D4 Series does the heavy lifting for you. It uses advanced algorithms to process raw image streams from the depth cameras and computes high resolution 3D depth maps without the need for dedicated GPU or host processor."

[alin45]

yes, we guess so. we highly think that the exposure of both the left and right camera are adjusted according to the lighting condition.

So how to use D435 especially outdoor to advoid these problems？

[MartyG]

In outdoor conditions, if it is too dark or too bright then you may get better results by turning off the camera's IR emitter component with scripting. The IR emitter assists the IR sensor with exposure but can cause the sensor to become saturated under dim or bright lighting conditions.

rs2::pipeline pipe;

rs2::pipeline_profile selection = pipe.start();

rs2::device selected_device = selection.get_device();

auto depth_sensor = selected_device.first();

if (depth_sensor.supports(RS2_OPTION_EMITTER_ENABLED))

{

depth_sensor.set_option(RS2_OPTION_EMITTER_ENABLED, 1.f); // Enable emitter

depth_sensor.set_option(RS2_OPTION_EMITTER_ENABLED, 0.f); // Disable emitter

}

if (depth_sensor.supports(RS2_OPTION_LASER_POWER))

{

// Query min and max values:

auto range = depth_sensor.get_option_range(RS2_OPTION_LASER_POWER);

depth_sensor.set_option(RS2_OPTION_LASER_POWER, range.max); // Set max power

depth_sensor.set_option(RS2_OPTION_LASER_POWER, 0.f); // Disable laser

}

If you are using the RealSense Viewer tool, you may also be interested to know that you can change the default visual processing settings to better suit your use of the camera.

https://github.com/IntelRealSense/librealsense/wiki/D400-Series-Visual-Presets D400 Series Visual Presets · IntelRealSense/librealsense Wiki · GitHub

[alin45]

thank you for your suggestion, we will test immediately.

BTW, do you know how to get the left and right images using API?

[MartyG]

If you want to get separate left and right images, my understanding is that it is very difficult due to how RealSense calculates depth. I remembered that someone did work out a method though.

[alin45]

sorry, I think this link cannot satisfy our requirement.

we only want raw images from left and right IR cameras.