Hi, I have a question about setting value effect of Manual / Auto exposure? When I change the setting to manual exposure, the depth image come out strangely. I would like to ask how the depth quality is affected by the setting value of manual exposure. And do you recommend auto exposure for depth performance? Can you tell me how each Manual / Auto exposure correlates with depth performance? For reference, the ExpTime value was 20000 as set by default when using the Manual exposure option. Best regards, Ryan.

Hi @RyanLee , I'd suggest playing around with https://docs.luxonis.com/projects/api/en/latest/samples/MonoCamera/mono_camera_control/ to see how exposure time affect image quality. If camera exposure is to high or too low, it is very difficult (impossible) to calculate disparity map which means we are unable to get depth from such setup. I'd recommend using auto exposure unless you want total control in rapidly changing/dynamic environments. 20000 is way too much for mono cameras 🙂 Hope this helps, Jaka

To add here: you'd always want to use AE, expecially if you aren't 100% sure what you are doing - that's why it's enabled by default 🙂. 20ms exposure might not be too high if sensitivity is (very) low, but it depends on the environment. Thanks, Erik

[unknown] [unknown] Hi we have additional question about this issue. we tested depth performance with OAK-D and OAK-D Pro. But based on our test results, OAK-D Pro is worse than OAK-D now. <OAK-D depth test> actual measurement | measurement | standard deviation (last 30 data) unit: m 0.4 0.3996 0.0004 0.8 0.7984 0.0010 1.2 1.1994 0.0028 1.6 1.5965 0.0056 2.0 1.9874 0.0085 2.5 2.4747 0.0109 3.0 2.9966 0.0144

@[deleted] and what are the results of the OAK-D-Pro? It might be that at close range the dot pattern isn't ideal and it makes the results worse.

Manual / Auto exposure correlates with depth performance?

RyanLee

jakaskerl erik

Thank you for you guys great support. we will try it out and then come back to you if anything more.

Best regards,

Ryan.

RyanLee

erik jakaskerl

Hi we have additional question about this issue.

we tested depth performance with OAK-D and OAK-D Pro. But based on our test results, OAK-D Pro is worse than OAK-D now.

<the result of OAK-D depth test>

actual measurement | measurement | standard deviation (last 30 data) unit: m

0.4 0.3996 0.0004

0.8 | 0.7984 | 0.0010

1.2 | 1.1994 | 0.0028

1.6 | 1.5965 | 0.0056

2.0 | 1.9874 | 0.0085

2.5 | 2.4747 | 0.0109

3.0 | 2.9966 | 0.0144

<the result of OAK-D-Pro depth test>

actual measurement measurement standard deviation (last 30 data) unit: m

0.4 | 0.4145 | 0.0004

0.8 | 0.8587 | 0.0016

1.2 | 1.3298 | 0.0026

1.6 | 1.8337 | 0.0059

2.0 | 2.3776 | 0.0084

2.5 | 3.1465 | 0.0196

3.0 | 3.9321 | 0.0334

So we tested OAK-D Pro with depth-preview.py.

I'm using depthai_ros noetic branch of gitgub, and I'm using stereo_inertial_node.launch from depthai_example package. But when i checked its hz(fps), it is working with 20hz. But we would expect 30 hz. i would like to cross-check it with you once more.
As a result of observing the depth for about 10 minutes at a specific distance (2m), it saw that the measured value gradually went down from 2.02m to 1.94m. do you have any solution for it?
i added all the back data for its investigation on the google drive. if you need anything more, please let us know we will follow up as soon as possible.

https://drive.google.com/drive/folders/1ECZGkdMZ8tsw4o2-hzUi-EzzWmKxVKS7?usp=share_link

Best regards,

Ryan.

erik

RyanLee Could you provide the full report of your depth testing - how everything was setup, measurement scripts used, and also recordings of the left/right streams and calibration, so we can re-do the tests locally?
As this is wildly inaccurate, and it doesn't seem that the calibration is way off, as the dispairty image looks ok.
Thanks, Erik

RyanLee

@"erik"#p7250

Sorry i posted my question during the editing. I uploaded all. And is it possible for me to give me the distance value? 2m or 3 m?? like this. And also why it is worse with close range?? we are wondering about it.

Thank you so much about your great help.

Best regards,

Ryan.

RyanLee

erik Hi

Here is the test method we did. if you need anything more, please feel free to let me know we will come back to you as soon as possible. we also try to prepare the left/right steams and calibration as well.

Test method (attach the measured depth data (0.4m ~ 3.0m))

We are using depthai_ros noetic branch of gitgub, and stereo_inertial_node.launch from depthai_example package.

Depth accuracy was tested by placing an appropriately sized box in front of the camera and moving it in the Z-axis direction relative to the camera frame.

We received the /stereo_inertial_publisher/stereo/depth topic of type sensor_msgs/Image and defined it as the depth to measure the average of 64 pixel data coming in front 8x8 (pixels).

The standard deviation in the third column is the standard deviation of the last 30 depth data measured for objects at a fixed distance.

actual measurement | measurement | standard deviation (last 30 data) unit: m

0.4 0.3996 0.0004

0.8 | 0.7984 | 0.0010

1.2 | 1.1994 | 0.0028

1.6 | 1.5965 | 0.0056

2.0 | 1.9874 | 0.0085

2.5 | 2.4747 | 0.0109

3.0 | 2.9966 | 0.0144

actual measurement | measurement | standard deviation (last 30 data) unit: m

0.4 | 0.4145 | 0.0004

0.8 | 0.8587 | 0.0016

1.2 | 1.3298 | 0.0026

1.6 | 1.8337 | 0.0059

2.0 | 2.3776 | 0.0084

2.5 | 3.1465 | 0.0196

3.0 | 3.9321 | 0.0334

Best regards,

Ryan.

erik

RyanLee Please provide measurement scripts and recordings of the left/right streams + calibration.

RyanLee

erik Ok we are preparing it. And i have one more quetion. is the way of recoding the calibration is below method? Please guide confirm or guide us, we will do our best to do it as soon as possible.

https://docs.luxonis.com/projects/api/en/latest/samples/calibration/calibration_reader/

Best regards,

Ryan.

erik

Hi RyanLee , Yes, calibration reader will provide the needed json so we can repro locally🙂
Thnaks, Erik

RyanLee

Hi Erik erik

Thank you for your support.

here is the information for you. please let me know if you need anything more.

calibration data

<calibration intrinsics>

left mono camera intrinsics in pixels:

[806.3150024414062, 0.0, 629.9376831054688]

[0.0, 806.3150024414062, 393.29144287109375]

[0.0, 0.0, 1.0]

right mono camera intrinsics in pixels:

[803.0247802734375, 0.0, 636.837646484375]

[0.0, 803.0247802734375, 413.8108215332031]

[0.0, 0.0, 1.0]
measurement scripts
recordings of the left/right streams

Thanks,

Best regards,

Ryan.

erik

Hi RyanLee , Could you please use https://github.com/luxonis/depthai-experiments/tree/master/gen2-record-replay for the recording of the data? We can't rerun stereo with screenrecording of left/right videos🙂
Thanks, Erik

RyanLee

Hi erik , Here is the videos you requested for it. Thanks and if you need anything more, please let me know.

https://drive.google.com/drive/folders/10NlCEroBSa6vJiW06urSTxJ3PjHFrBDT?usp=share_link

Best regards,

Ryan.

erik

RyanLee Could you crosscheck (with a laser distance meter) what the actual distance to the box is on the video taken above? It looks like 143cm to me, so I would like to know ground truth.
Thanks, Erik

RyanLee

erik Hi Erik

The actual distance is 128cm. I hope it may help.

Best regards,

Ryan.