Zed 4.0.6 - Broken python library

Software Python
1

With https://stereolabs.sfo2.cdn.digitaloceanspaces.com/zedsdk/4.0/ZED_SDK_Ubuntu20_cuda11.8_v4.0.6.zstd.run pyzed fails to import. This previously worked on 4.0.6, but no longer does.

> python
Python 3.10.13 
>>> import pyzed.sl as sl
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: /...python3.10/site-packages/pyzed/sl.cpython-310-x86_64-linux-gnu.so: undefined symbol: _ZN2sl6Camera19getRegionOfInterestERNS_3MatENS_10ResolutionE
>>>

This happens even after re-running

> python /usr/local/zed/get_python_api.py
2

This is fixed in 4.0.7, but that neural depth model performs worse.

3

Hi,
This is because get_python_api.py returns the latest python module, which is now 4.0.8. The compatibility was not there between 4.0.7 and 4.0.6 because the API changed within the same minor version. We will avoid that in future patches, it was because of the early access. Sorry again.
If you still want to use 4.0.6 and the python module, you can build it yourself from the repo GitHub - stereolabs/zed-python-api: Python API for the ZED SDK. It’s actually quite easy.

It’s very suprising that you found difference between NEURAL version 4.0.6 and 4.0.7 since it did not change. Is it still the case with 4.0.8 ? Can you send a SVO so that we can investigate ?

4

I can still get an SVO if needed, but the changelog did say the network changed. 4.0.7 Confidence Ranges Changed - #4 by Myzhar

The issue now is in scenes that would’ve previously had points almost everywhere, we get large patches of completely empty space when using low confidence_thresholds

5

Indeed, the confidence ranges was retuned - however if you modify the confidence, you can get the same quality as you had before. It’s just that low confidences are now really low, whereas they were still quite high before.

6

The issue is it’s really hard to know what the mapping from old confidence values to new confidence values is. The changelog and docs provided no guidance on this issue. If you can provide more guidance now it’d be very helpful

7

Of course ! Can you tell me what your old confidence value was ?

8

It was 0. On 4.0.7, 0 returns no values.

9

Can you try with the value 1 ?

10

I have tried many confidence values. None consistently perform in a similar manner. Do you have the python whl for 4.0.6? I would like to manually install it. The depth model 4.0.7+ is not viable.

11

I’m also ok with building it from source https://github.com/stereolabs/zed-python-api/tree/master/src if you can direct me to the correct commit.

12

Hi,
Really sorry about this. I can reproduce your behavior a little:

image
image1027×597 100 KB

image
image1027×597 86.3 KB

This two images are taken from 4.0.5 and 4.0.8. The one with more black is 4.0.6 at 0%, the other is 4.0.8 at 1%. I guess the confidence is still too high for you ? If you can send a SVO file, it can really help us understand the issue better. I thought that you actually had less points than before, but in my tests I get more.

What you can try is to remove the NEURAL model from /usr/local/zed/resources, to force a reoptimizations. You’ll be sure you have a fresh installation.

In the meantime, here is the python wrapper for 4.0.6.
pyzed.zip (929.6 KB)

13

Do you have the 4.0.6 wheel file? Alternatively, how do I convert the zip you sent to a wheel.

I was able to build the 4.0.8 egg from source, but didn’t see how to produce a wheel file from that. The building also failed for me for sdk versions <4.0.8 on any of the 5 most recent commits of the python-sdk repo.

I observed a similar change in the number of points between 4.0.6 and 4.0.7. In almost every case there were more points in 4.0.7+ with a confidence threshold of 1% compared to <4.0.7 with a confidence of 0. However, in <5% of cases the 4.0.7+ model with confidences ranging between (1 and 5) would catastrophically return no points for about 1/4 of the entire scene. These scenes were all within the min/max depth runtime parameters and similar to the scenes we had successfully operated in with <4.0.7.

I’d like to send you an SVO, but don’t have any available and struggle to reproduce this issue whenever SVO recording is an option. Is there a way to use the SDK normally/live and also record SVOs?

Also if you have an email/slack/discord we could use to communicate I can share more details than I am comfortable doing on this forum.

14

Hi again,

You can just replace the files I sent you in the repo from github (latest vesion). Then do what is in the readme.
Alternatively, send me you platform and python version and I will build you it. I guess, Python3.10, Ubuntu20 ? If that’s the case, here it is:
pyzed-4.0-cp310-cp310-linux_x86_64.whl (622.9 KB)

15

Thank you for the wheel. I’ll work on getting SVO files, but it will take a while

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