cv2 module members are not recognized

Question

cv2 module members are not recognized

uriva opened this issue 6 years ago · comments

When importing cv2 I get errors such as:

[pylint] E1101:Module 'cv2' has no 'imread' member
[pylint] E1101:Module 'cv2' has no 'resize' member
[pylint] E1101:Module 'cv2' has no 'imshow' member
[pylint] E1101:Module 'cv2' has no 'waitKey' member
[pylint] E1101:Module 'cv2' has no 'destroyAllWindows' member

etc'

(the code itself runs fine)

I'm using VSCode 1.26.1 and Python 3.6.5.

See this issue for more complaints: https://github.com/DonJayamanne/pythonVSCode/issues/623

Naman Dutta commented 5 years ago

thanks

Claudiu Popa · Answer 1 · Tue Aug 21 2018 14:12:22 GMT+0800 (China Standard Time)

This should work if you pass --extension-pkg-whitelist=cv2 to pylint as in pylint --extension-pkg-whitelist=cv2 .... The reason for this is that cv2 seems to be an extension package, thus it's C code that pylint cannot understand. The extension whitelist flag lets pylint import cv2 in order to build an AST out of the imported cv2 module.

uriva · Answer 2 · Tue Aug 21 2018 15:02:20 GMT+0800 (China Standard Time)

To future readers, in vsc this means adding this line to the settings:
"python.linting.pylintArgs": ["--extension-pkg-whitelist=cv2"]

Ciprian Tomoiaga · Answer 3 · Wed Sep 12 2018 23:57:07 GMT+0800 (China Standard Time)

Thanks @PCManticore

However, even with the extension enables, pylint still doesn't recognise 2nd level members, such as cv2.ml.KNearest_create() or cv2.ximgproc.thinning().

I believe it is the same case as #779 ?

Ciprian Tomoiaga · Answer 4 · Thu Dec 06 2018 06:58:15 GMT+0800 (China Standard Time)

@ashraf-minhaj use the Cmd+shift+p shortcut (or ctrl instead of cmd) and type "open settings (json)". There should be an option which opens the json settings and you can add the line there

David Cardozo · Answer 5 · Sat Jan 12 2019 19:07:45 GMT+0800 (China Standard Time)

I'm encountering the same situation:

dgromov@Predator-G3-571 ~/D/u/s/p/CarND-Advanced-Lane-Lines> pylint camera_calibration.py --extension-pkg-whitelist=cv2 | tail                                                                                                       (SDCND) 
camera_calibration.py:157:18: E1101: Module 'cv2' has no 'undistort' member (no-member)
camera_calibration.py:159:12: E1101: Module 'cv2' has no 'imshow' member (no-member)
camera_calibration.py:160:12: E1101: Module 'cv2' has no 'waitKey' member (no-member)
camera_calibration.py:162:12: E1101: Module 'cv2' has no 'imwrite' member (no-member)
camera_calibration.py:163:12: E1101: Module 'cv2' has no 'destroyAllWindows' member (no-member)
camera_calibration.py:129:0: R1711: Useless return at end of function or method (useless-return)

----------------------------------------------------------------------
Your code has been rated at -12.67/10 (previous run: -12.67/10, +0.00)

dgromov@Predator-G3-571 ~/D/u/s/p/CarND-Advanced-Lane-Lines> conda list | grep  "pylint\|astroid"                                                                                                                                    (SDCND) 
astroid                   2.1.0                    py36_0  
pylint                    2.2.2                    py36_0

Claudiu Popa · Answer 6 · Sun Jan 13 2019 21:51:43 GMT+0800 (China Standard Time)

As mentioned, most of the errors should be already solved by using --extension-pkg-whitelist=cv2. But unfortunately, as @cipri-tom mentioned, there are a couple of cv2 modules for which that flag does not work. I think the best way forward is for someone to propose a patch to astroid, the library that pylint uses for infererence, to add support for cv2 in a similar fashion to how we added for numpy in #779. Unfortunately we're not familiar with cv2 so it's not something that we'd do ourselves.

Mehdi · Answer 7 · Tue Mar 26 2019 22:53:02 GMT+0800 (China Standard Time)

https://www.bilibili.com/video/av33693850/
"python.linting.pylintArgs": ["--generate-members"]

Satyajith · Answer 8 · Fri May 03 2019 21:01:39 GMT+0800 (China Standard Time)

For me, pylint cannot process cv2 when I build cv2 from source. Works when installed using pip.

HamedGhasemi · Answer 9 · Mon Jun 10 2019 04:37:14 GMT+0800 (China Standard Time)

@mehanton this works for me.

Thank you. :)

Lintang Wisesa · Answer 10 · Thu Jun 13 2019 10:37:49 GMT+0800 (China Standard Time)

On VScode: CTRL + Shift + P
Choose "Preferences: Open Settings (JSON)"
Add this line into JSON file:
"python.linting.pylintArgs": ["--generate-members"]
Done, it works for me 👍

Harsh Patel · Answer 11 · Fri Jul 05 2019 00:02:04 GMT+0800 (China Standard Time)

On VScode: CTRL + Shift + P

Choose "Preferences: Open Settings (JSON)"

Add this line into JSON file:
"python.linting.pylintArgs": ["--generate-members"]

Done, it works for me 👍

Thanks, man! it worked for me too

N. YC. Kim · Answer 12 · Tue Jul 23 2019 11:44:40 GMT+0800 (China Standard Time)

on VSCode Ubuntu I did "python.linting.pylintArgs": ["--generate-members", "--extension-pkg-whitelist=cv2"] which worked.

박인성 (InSung Bahk) · Answer 13 · Sun Jul 28 2019 08:27:30 GMT+0800 (China Standard Time)

On VScode: CTRL + Shift + P

Choose "Preferences: Open Settings (JSON)"

Add this line into JSON file:
"python.linting.pylintArgs": ["--generate-members"]

Done, it works for me 👍

Hm.... I can't edit "defaultSetting.json file....

Lintang Wisesa · Answer 14 · Sun Jul 28 2019 11:07:18 GMT+0800 (China Standard Time)

On VScode: CTRL + Shift + P

Choose "Preferences: Open Settings (JSON)"

Add this line into JSON file:
"python.linting.pylintArgs": ["--generate-members"]

Done, it works for me 👍

Hm.... I can't edit "defaultSetting.json file....

@insung3511 It must be "settings.json", not "defaultSetting.json"! Make sure you choose "Preferences: Open Settings (JSON)", not "Preferences: Open Default Settings (JSON)" 👌

funny860 · Answer 15 · Tue Aug 13 2019 21:12:48 GMT+0800 (China Standard Time)

thanks for the help guys

Xu · Answer 16 · Wed Aug 21 2019 11:22:46 GMT+0800 (China Standard Time)

The "--generate-members" option is wrong!
It works because pylint fails.
The command "pylint --generate-members test.py" fails because of "no such option: --generate-members".

Xu · Answer 17 · Wed Aug 21 2019 11:49:15 GMT+0800 (China Standard Time)

Look at this, but the solution mentioned here won't work either.
It seems that the only solution is to disable the "no-member" error.

rivergold · Answer 18 · Mon Oct 14 2019 15:53:22 GMT+0800 (China Standard Time)

The "python.linting.pylintArgs": ["--generate-members"] is wrong, it will make pylint not work.
The correct way is to set ""python.linting.pylintArgs": ["--generated-members=cv2.*"] which only config for cv2, reference @bjtho08 reply in #779.

t31060 · Answer 19 · Fri Mar 06 2020 14:25:44 GMT+0800 (China Standard Time)

i compiled opencv from soruce and passed the args to pylitn but still intellisense doesnt work, there is another way to solve?

Saksham2dubey · Answer 20 · Thu Mar 26 2020 22:27:16 GMT+0800 (China Standard Time)

I also facing the same problem of "cv2 module members are not recognized
"
what I did was
after importing cv2
write:
from cv2 import cv2
this worked for me because my JSON is not amendable

Julián Toledano · Answer 21 · Sat Apr 18 2020 01:59:51 GMT+0800 (China Standard Time)

On VScode: CTRL + Shift + P

Choose "Preferences: Open Settings (JSON)"

Add this line into JSON file:
"python.linting.pylintArgs": ["--generate-members"]

Done, it works for me +1

Hm.... I can't edit "defaultSetting.json file....

Now my pylint just don't show any erros 😅

Julián Toledano · Answer 22 · Sat Apr 18 2020 02:04:47 GMT+0800 (China Standard Time)

The "python.linting.pylintArgs": ["--generate-members"] is wrong, it will make pylint not work.
The correct way is to set ""python.linting.pylintArgs": ["--generated-members=cv2.*"] which only config for cv2, reference @bjtho08 reply in #779.

Thanks that solves it.

On VScode: CTRL + Shift + P
Choose "Preferences: Open Settings (JSON)"
Add this line into JSON file: "python.linting.pylintArgs": ["--generated-members=cv2.*"]
Done, it works for me +1

Farrukh Rahman · Answer 23 · Mon Jun 01 2020 09:11:10 GMT+0800 (China Standard Time)

I tried above and still no luck.

akash-falcon1999 · Answer 24 · Fri Jul 17 2020 03:17:50 GMT+0800 (China Standard Time)

https://www.bilibili.com/video/av33693850/
"python.linting.pylintArgs": ["--generate-members"]

works now thanks

Bjarne Thorsted · Answer 25 · Fri Jul 17 2020 20:21:29 GMT+0800 (China Standard Time)

The "python.linting.pylintArgs": ["--generate-members"] is wrong, it will make pylint not work.
The correct way is to set ""python.linting.pylintArgs": ["--generated-members=cv2.*"] which only config for cv2, reference @bjtho08 reply in #779.

Thanks that solves it.

On VScode: CTRL + Shift + P

Choose "Preferences: Open Settings (JSON)"

Add this line into JSON file: "python.linting.pylintArgs": ["--generated-members=cv2.*"]

Done, it works for me +1

@akash-falcon1999 that pylintarg is wrong, as you can see in the above. It will make any error and any warning from pylint disappear, even those that are supposed to be there. Trust me, you don't want to pass that pylintarg. Better to live with this bug, because it actually is a bug in pylint.

akash-falcon1999 · Answer 26 · Sat Jul 18 2020 00:56:20 GMT+0800 (China Standard Time)

The "python.linting.pylintArgs": ["--generate-members"] is wrong, it will make pylint not work.
The correct way is to set ""python.linting.pylintArgs": ["--generated-members=cv2.*"] which only config for cv2, reference @bjtho08 reply in #779.

Thanks that solves it.

On VScode: CTRL + Shift + P

Choose "Preferences: Open Settings (JSON)"

Add this line into JSON file: "python.linting.pylintArgs": ["--generated-members=cv2.*"]

Done, it works for me +1

@akash-falcon1999 that pylintarg is wrong, as you can see in the above. It will make any error and any warning from pylint disappear, even those that are supposed to be there. Trust me, you don't want to pass that pylintarg. Better to live with this bug, because it actually is a bug in pylint.

@bjtho08 Thanks ,rectified it,was quite bugged off with those bugs,although the code was working fine.

Rishabh Kothari · Answer 27 · Sat Jul 18 2020 21:17:20 GMT+0800 (China Standard Time)

On VScode: CTRL + Shift + P

Choose "Preferences: Open Settings (JSON)"

Add this line into JSON file:
"python.linting.pylintArgs": ["--generate-members"]

Done, it works for me 👍

Do we need to install json extension in vscode for this?

Bjarne Thorsted · Answer 28 · Sat Jul 18 2020 21:28:37 GMT+0800 (China Standard Time)

@rishabh547 see my comment above

Rishabh Kothari · Answer 29 · Sat Jul 18 2020 23:00:24 GMT+0800 (China Standard Time)

@rishabh547 see my comment above

So basically after adding that line in the file save the file right? That's it?

Rishabh Kothari · Answer 30 · Sat Jul 18 2020 23:01:14 GMT+0800 (China Standard Time)

Please help me I am low-key getting depressed because of this error, I have spent hours on this still unable to rectify!

Rishabh Kothari · Answer 31 · Sun Jul 19 2020 00:07:37 GMT+0800 (China Standard Time)

I tried above and still no luck.

Hey did you solve your issue? If so how

Bjarne Thorsted · Answer 32 · Mon Jul 20 2020 15:22:55 GMT+0800 (China Standard Time)

@rishabh547 you misunderstood. The line you wrote is wrong and will make pylint fail silently, thus making it appear as if your code has zero errors. You need to use the pylint key-value argument that is written in my comment. That will solve your issue without causing pylint to fail.

Shivam Mukherjee · Answer 33 · Tue Jul 21 2020 13:43:51 GMT+0800 (China Standard Time)

This doesn't seem to be bringing up cv2 in the autocomplete suggestions.
Moreoever, hovering over cv2 shows this:

I built opencv from source, so this points to the cv2 module under "../opencv/build/python-loader".
While the errors are all gone, no autocomplete suggestions come up. Is this intended?

Bjarne Thorsted · Answer 34 · Tue Jul 21 2020 14:11:47 GMT+0800 (China Standard Time)

@SHIVAMMUKHERJEE autocomplete is not handled by pylint, but rather the languageserver. You will have to look at Microsofts languageserver (or jedi, if you use that one) for a solution.

Shivam Mukherjee · Answer 35 · Tue Jul 21 2020 14:21:59 GMT+0800 (China Standard Time)

@bjtho08 no dice there, sigh. It's funny that the REPL somehow does this easily.

Shinit Shetty · Answer 36 · Fri Aug 07 2020 12:46:21 GMT+0800 (China Standard Time)

To future readers, in vsc this means adding this line to the settings:
"python.linting.pylintArgs": ["--extension-pkg-whitelist=cv2"]

how to add this line to settings???

Shivam Mukherjee · Answer 37 · Fri Aug 07 2020 13:21:19 GMT+0800 (China Standard Time)

@Shinit5201

Shinit Shetty · Answer 38 · Fri Aug 07 2020 14:00:27 GMT+0800 (China Standard Time)

Thanks

…

On 07-Aug-2020, at 10:51 AM, Shivam Mukherjee ***@***.***> wrote: @Shinit5201 <https://github.com/Shinit5201> <https://user-images.githubusercontent.com/12777564/89611882-ea42d380-d89b-11ea-959c-92d43a821240.png> — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#2426 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/APVLRH3TAOJMCQRBJZ5VC33R7OFN3ANCNFSM4FQPTXBA>.

Kshitij Agarwal · Answer 39 · Fri Sep 04 2020 14:52:24 GMT+0800 (China Standard Time)

After reading such complex tasks, I was totally surprised.

A very simple way is:
Instead of import cv2 import from cv2 import cv2

It works like a charm.

Shivam Mukherjee · Answer 40 · Fri Sep 04 2020 15:00:35 GMT+0800 (China Standard Time)

After reading such complex tasks, I was totally surprised.

A very simple way is:
Instead of import cv2 import from cv2 import cv2

It works like a charm.

You could also take a step further and import even more granularly into individual classes or features instead of the whole module!

Kritika Parmar · Answer 41 · Wed Sep 09 2020 03:12:39 GMT+0800 (China Standard Time)

After reading such complex tasks, I was totally surprised.

A very simple way is:
Instead of import cv2 import from cv2 import cv2

It works like a charm.

It worked dude!!😁

Dorian Portillo · Answer 42 · Sun Sep 27 2020 07:44:46 GMT+0800 (China Standard Time)

After reading such complex tasks, I was totally surprised.

A very simple way is:
Instead of import cv2 import from cv2 import cv2

It works like a charm.

a simple solution wow thank you

Zhuo Zhang · Answer 43 · Mon Sep 28 2020 19:42:35 GMT+0800 (China Standard Time)

"python.linting.pylintArgs": ["--generate-members"] works for me.

Btw, tts 2020-09-28 already, why people still have to setup this stuff for pylint?

Bjarne Thorsted · Answer 44 · Mon Sep 28 2020 20:30:15 GMT+0800 (China Standard Time)

"python.linting.pylintArgs": ["--generate-members"] works for me.

Btw, tts 2020-09-28 already, why people still have to setup this stuff for pylint?

That argument is wrong and will make pylint fail silently. See the comments earlier in the thread for an explanation.

jofrev · Answer 45 · Sun Oct 11 2020 17:58:22 GMT+0800 (China Standard Time)

After reading such complex tasks, I was totally surprised.

A very simple way is:
Instead of import cv2 import from cv2 import cv2

It works like a charm.

It won't report an error in VS Code's problems tab any longer that's true. But if you run pylint from your terminal you'll still get

I1101: Module 'cv2.cv2' has no 'imread' member, but source is unavailable. Consider adding this module to extension-pkg-whitelist if you want to perform analysis based on run-time introspection of living objects. (c-extension-no-member)

with from cv2 import cv2 instead of

E1101: Module 'cv2' has no 'imread' member (no-member)

with import cv2. Depending on how one intends to use pylint, whitelisting cv2 in pylint settings as described numerous times above may actually be better.

Gautam Jain · Answer 46 · Wed Oct 14 2020 19:08:01 GMT+0800 (China Standard Time)

@Shinit5201

this is not working for me I am using Opencv 4.1.0 build from source in an anaconda environment.

AZMYIN MD KAMAL · Answer 47 · Sat Nov 28 2020 13:03:36 GMT+0800 (China Standard Time)

On VScode: CTRL + Shift + P

Choose "Preferences: Open Settings (JSON)"

Add this line into JSON file:
"python.linting.pylintArgs": ["--generate-members"]

Done, it works for me 👍

Worked for me too. Thanks

Ahamed Ruyefa · Answer 48 · Thu Apr 29 2021 16:56:31 GMT+0800 (China Standard Time)

I also facing the same problem of "cv2 module members are not recognized
"
what I did was
after importing cv2
write:
from cv2 import cv2
this worked for me because my JSON is not amendable

Thanks! worked for me too

Nano Miratus · Answer 49 · Sun Sep 05 2021 16:39:28 GMT+0800 (China Standard Time)

I can't believe how many people here are recommending to edit the clumsy vscode setting "python.linting.pylintArgs".

Not only is it just solving the issue locally, especially when you edit your global vscode settings.json, it also overrides any settings from a .pylintrc file, which is not immediately obvious. Using vscode's settings to add command line arguments to some binary running in the background is a bad idea in general, and should only be done as a last resort.

What you should really do, in my opinion, is to generate a pylint configuration file inside your project folder like this:

pylint --generate-rcfile > .pylintrc

and then edit the settings extension-pkg-allow-list and generated-members there.

You can of course also edit these settings in your user- or system-wide .pylintrc, I'd advise against that though.

Domagoj · Answer 50 · Sat Nov 13 2021 06:56:24 GMT+0800 (China Standard Time)

I can't believe how many people here are recommending to edit the clumsy vscode setting "python.linting.pylintArgs".

Not only is it just solving the issue locally, especially when you edit your global vscode settings.json, it also overrides any settings from a .pylintrc file, which is not immediately obvious. Using vscode's settings to add command line arguments to some binary running in the background is a bad idea in general, and should only be done as a last resort.

What you should really do, in my opinion, is to generate a pylint configuration file inside your project folder like this:
pylint --generate-rcfile > .pylintrc
and then edit the settings extension-pkg-allow-list and generated-members there.

You can of course also edit these settings in your user- or system-wide .pylintrc, I'd advise against that though.

This. By far the most elegant solution. Thanks!

KukavicaHome · Answer 51 · Sun Feb 20 2022 02:05:56 GMT+0800 (China Standard Time)

VS2019 works for me.

Quyet Nguyen · Answer 52 · Thu Jul 14 2022 10:50:06 GMT+0800 (China Standard Time)

install opencv_headless and it works for me.

Zhiliang · Answer 53 · Sun Apr 23 2023 17:02:09 GMT+0800 (China Standard Time)

For pyproject.toml file, add the following

[tool.pylint.typecheck]
generated-members = "cv2.*"

Pierre Sassoulas · Answer 54 · Sun Apr 23 2023 18:26:00 GMT+0800 (China Standard Time)

Note that using genrated-members should be the last solution if nothing else work, because it will disable pylint's check on everything coming from cv2.

knowledgeLover · Answer 55 · Mon Jul 17 2023 06:42:56 GMT+0800 (China Standard Time)

pip installation is wrong.

Easiest solution and you do not need to worry about any settings or incorrect changes. Much safer.

pip install opencv-python-headless

Try installing opencv-python-headless python dependency instead of opencv-python. That includes a precompiled binary wheel with no external dependencies (other than numpy), and is intended for headless environments like Docker. This saved almost 700mb in my docker image compared with using the python3-opencv Debian package (with all its dependencies).

The package documentation discusses this and the related (more expansive) opencv-contrib-python-headless pypi package.