67
votes

I have installed opencv on my windows machine using python 3.6 without any issues, using:

pip install opencv-python

but when I try to import cv2 I get the following error

ImportError: DLL load failed: The specified module could not be found.

I have seen this post

It says cv2 doesn't work with python 3 I was wondering if this has been fixed or if there is a way around it

22
The latest supported version of python in OpenCV is 3.5 not 3.6kmario23
@kmario23: I tried with Python 3.5.0 and I still get the same error.Stefan Monov
Check out the answer of @tientuyen07, it works for me. For python3.7.0 on Windows10.roachsinai
Note cv2 definitely works with Python3 nobody should be using Python 2 any more! :)eric
I had it installed with conda. After uninstalling it and reinstalling using pip, it worked.toliveira

22 Answers

52
votes

You can download the latest OpenCV 3.2.0 for Python 3.6 on Windows 32-bit or 64-bit machine, look for file starts withopencv_python‑3.2.0‑cp36‑cp36m, from this unofficial site. Then type below command to install it:

  • pip install opencv_python‑3.2.0‑cp36‑cp36m‑win32.whl (32-bit version)
  • pip install opencv_python‑3.2.0‑cp36‑cp36m‑win_amd64.whl (64-bit version)

I think it would be easier.

Update on 2017-09-15:

OpenCV 3.3.0 wheel files are now available in the unofficial site and replaced OpenCV 3.2.0.

Update on 2018-02-15:

OpenCV 3.4.0 wheel files are now available in the unofficial site and replaced OpenCV 3.3.0.

Update on 2018-06-19:

OpenCV 3.4.1 wheel files are now available in the unofficial site with CPython 3.5/3.6/3.7 support, and replaced OpenCV 3.4.0.

Update on 2018-10-03:

OpenCV 3.4.3 wheel files are now available in the unofficial site with CPython 3.5/3.6/3.7 support, and replaced OpenCV 3.4.1.

Update on 2019-01-30:

OpenCV 4.0.1 wheel files are now available in the unofficial site with CPython 3.5/3.6/3.7 support.

Update on 2019-06-10:

OpenCV 3.4.6 and OpenCV 4.1.0 wheel files are now available in the unofficial site with CPython 3.5/3.6/3.7 support.

60
votes

I took a lot of time to solve this error! Run command

pip install opencv-contrib-python
39
votes

If you are using Anaconda with python 3.5, this is a problem in the Anaconda release. (Refer this issue)

You can fix this issue by copying python3.dll file to Anaconda3 folder (where python.exe is located)

How to get "python3.dll"

  • In cmd, type python --version to find whether your installation is 64-bit or 32-bit
  • download python 3.x embeddable zip file from here
  • Extract the zip file and copy python3.dll file to Anaconda3 folder

But if you can move to Anaconda with python 3.6 you will not face this issue. If it is possible for you, then it is the recommended way..

20
votes

Recently I have faced the similar issue in Azure Windows Server 2012 r2 . Tried all option with and without Anaconda but none of them helped. After lot of findings I found that mfplat.dll was missing which is related to Window Media Service.

Hence you have to manually install the features so that you can get dll related to window media service.

1.Turn windows features on or off

2.Skip the roles screen and directly go to Feature screen

3.Select "Desktop Experience" under "User Interfaces and Infrastructure"

After this all required dll of media services for opencv would be available.

So if you are planning to run your code in cloud(Window Server) then please dont forget to select Desktop Experience feature.

12
votes

I ran into this problem on Windows 10 (N) with a new Anaconda installation based on Python 3.7 (OpenCV version 4.0). None of the above advice helped (such as installing OpenCV from the unofficial site nor installing VC Redistributable).

I checked DLL dependencies of ...\AppData\Local\conda\conda\envs\foo\Lib\site-packages\cv2\cv2.cp37-win_amd64.pyd using dumpbin.exe according to this github issue. I noticed a library MF.dll, which I figured out belongs to Windows Media Foundation.

So I installed Media Feature Pack for N versions of Windows 10 and voilà, the issue was resolved!

8
votes

After spending too much time on this issue and trying out all different answers, here is what found:

  • The accepted answer by @thewaywewere is no longer applicable. I think this was applicable when opencv-python module still wasn't available.

  • This is indeed a bug in Anaconda 4.2 because they forgot to ship python3.dll. They have fixed this in next releases but unfortunately 4.2 is the last release with Python 3.5 as default. If you are stuck with Python 3.5 (for example VS2015 is only aware of versions up to 3.5) then you must manually download python3.dll as described in answer by @Ramesh-X.

  • If you can move on to Python 3.6 (which at present bit difficult if you are using OpenCV and VS2015) then just install latest Anaconda version and you don't have to deal with any of these.

6
votes

There are many questions on that and many suggestions. None of them helped me for the recent Opencv 3.4.16 and Python 3.6/3.7. Finally I switched to Pyhon 2.7.15 and installed opencv 3.1.0. The DLL-problem was solved.

When I look in cv2.pyd with dependency walker, the 3.1 has no dependency to one missing dll. Opencv 3.4 has this missing dependency to this dll:

API-MS-WIN-DOWNLEVEL-SHLWAPI-L1-1-0.DLL

may be this is the problem.

P.S.: I have Win7 pofessional 64Bit, 32Bit Python 2.7.15

3
votes

Frankly there are a lot of very smart and complicated answers here. Mine is dumb and simple. I deleted my conda environment, re-installed from scratch, taking pains to install opencv first. This fixed my problems. Environments are meant to be temporary and diaphanous -- don't get too attached.

So if my environment was called fubar first make sure every instance is deactivated (including any IDEs that are using it). Then remove it:

conda remove --name fubar --all

Now I simply recreate my environment and add opencv first:

conda create --name fubar
conda activate fubar
conda install opencv

And then go from there. First open python and make sure import cv2 works. Then you should be on your way. Note I always (always) install Spyder last as it tends to screw things up when I don't.

Note, if that doesn't work, we have had some cases where people have to uninstall and reinstall Anaconda, and then things worked. Obviously a last resort.

1
votes

I had the same issue when installing opencv 2.4.13 on Anaconda3 (Python 3.6)... I managed to fix this issue by reverting to Anaconda2 (Python 2.7)

1
votes

this happens because the compiler or the interpreter is finding more than one package of the file, delete all the number of same package you have and then keep only one and then try to install. It serves

1
votes

The issue is due to the missing python3.dll file in Anaconda3.

To fix the issue, you should simply copy the python3.dll to C:\Program Files\Anaconda3 (or wherever your Anaconda3 is installed).

You can get the python3.dll by downloading the binaries provided at the bottom of the Python's Release page and extracting the python3.dll from the ZIP file.

1
votes

I had the same issue with python 3.6(Anaconda3) and OpenCV 3.4.1 for spyder to work. Even after copying cv2.pyd into Anaconda3 Users/home/Anaconda3/Lib/site-packages, it didn't work.

But found a solution

Later I installed OpenCV and Dlib on Anaconda and copied the generated cv2.cp36-win_amd64.pyd and dlib.cp36-win_amd64.pyd into Anaconda3 Users/home/Anaconda3/Lib/site-packages. These can be copied from environment folder C:\Users\home\Anaconda3\envs\opencv\Lib\site-packages.

Finally spyder started to work

1
votes

In my case a major update of Windows 10 removed some Windows packages, so other methods (reinstalling opencv etc.) did not help. To fix it, install:

a) Microsoft Visual C++ Redistributable for Visual Studio 2015, 2017 and 2019

b) Media Feature Pack for N versions - needed only if you have Windows 10 N

Both need restart of PC.

0
votes

I have the same problem. when I install WinPython programming, and run opencv after copy the cv2.pyd file from my opencv directory, it will be like this: C:\Users.....\Downloads\opencv\build\python\2.7\x64, x64 or x86 is depend on your 32 or 64 bit devices. and paste to C:\Users.....\Downloads\WinPython-64bit-3.5.4.1Qt5\python-3.5.4.amd64\Lib\site-packages, I prefer the previous python 3.5 than 3.6. Because when I "import cv2" installed (python 3.6) it shows directly: "ImportError: DLL load failed: The specified module could not be found" Then I install python 3.5 and open WinPyhton Command prompt and type "pip install opencv-python".

The command prompt download opencv automatically, it shows the process like this "Successfully installed opencv-python-3.3.0.10"

Finally, I try to run open cv by type "import cv2", it works i try to type "cv2.version", and shows: '3.3.0'

0
votes

Under Winpython : the Winpython-64bit-.../python_.../DLLs directory the file cv2.pyd should be renamed to _cv2.pyd

0
votes

(base) C:\WINDOWS\system32>conda install C:\Users\Todd\Downloads\opencv3-3.1.0-py35_0.tar.bz2

I ran this command from anaconda terminal after I downloaded the version from https://anaconda.org/menpo/opencv3/files

This is the only way I could get cv2 to work and I tried everything for two days.

0
votes

If this helps someone, on official python 3.6 windows docker image, to make this thing work I had to copy following libraries from my desktop:

C:\windows\system32

aepic.dll
avicap32.dll
avifil32.dll
avrt.dll
Chakra.dll
CompPkgSup.dll
CoreUIComponents.dll
cryptngc.dll
dcomp.dll
devmgr.dll
dmenterprisediagnostics.dll
dsreg.dll
edgeIso.dll
edpauditapi.dll
edputil.dll
efsadu.dll
efswrt.dll
ELSCore.dll
evr.dll
ieframe.dll
ksuser.dll
mf.dll
mfasfsrcsnk.dll
mfcore.dll
mfnetcore.dll
mfnetsrc.dll
mfplat.dll
mfreadwrite.dll
mftranscode.dll
msacm32.dll
msacm32.drv
msvfw32.dll
ngcrecovery.dll
oledlg.dll
policymanager.dll
RTWorkQ.dll
shdocvw.dll
webauthn.dll
WpAXHolder.dll
wuceffects.dll

C:\windows\SysWOW64

aepic.dll
avicap32.dll
avifil32.dll
avrt.dll
Chakra.dll
CompPkgSup.dll
CoreUIComponents.dll
cryptngc.dll
dcomp.dll
devmgr.dll
dsreg.dll
edgeIso.dll
edpauditapi.dll
edputil.dll
efsadu.dll
efswrt.dll
ELSCore.dll
evr.dll
ieframe.dll
ksuser.dll
mfasfsrcsnk.dll
mfcore.dll
mfnetcore.dll
mfnetsrc.dll
mfplat.dll
mfreadwrite.dll
mftranscode.dll
msacm32.dll
msvfw32.dll
oledlg.dll
policymanager.dll
RTWorkQ.dll
shdocvw.dll
webauthn.dll
wuceffects.dll`
0
votes

Please Remember if you want to install python package/libraries for windows,

you should always consider Python unofficial Binaries

Step 1:

Search for your package, download dependent version 2.7 or 3.6 you can find it under Downloads/your_package_version.whl its called python wheel

Step 2:

Now install using pip,

pip install ~/Downloads/your_packae_ver.whl

this will install without any error.

0
votes

I had the same problem and spent 3 full days wrestling with it. I tried everything suggested: upgrading pip, updating Visual C++, updating Anaconda, manually downloading files and basically every solution I could find on the web. Here's what finally worked maybe it'll help someone else:

1- I ditched Python 3 and Anaconda-based downloads since I noticed they had several problems and downloaded Python 2.7.16 64-bits instead.

2- Navigated to where Pip was located on my drive (for me the path is C:\Python27\Scripts) highlighted the path by selecting it, and typed "cmd" then enter so the Command Prompt opens on that path (I noticed skipping this usually brings about a couple errors)

3- Updated Pip using python -m pip install --upgrade pip on the CMD (again, skipping this and not updating it didn't let this procedure go through)

4- Downloaded the appropriate Wheel file from https://www.lfd.uci.edu/~gohlke/pythonlibs/#opencv (after trying several the one that worked for me was opencv_python-2.4.13.7-cp27-cp27m-win_amd64.whl) I copy-pasted it to the same folder Pip was in (C:\Python27\Scripts for me) and then installed it through CMD using: pip install opencv_python-2.4.13.7-cp27-cp27m-win_amd64.whl. Always through CMD opened on that path as showed in step 2

5- After step 4 when I imported OpenCV using import cv2 I didn't have the DLL error anymore but an error related to numpy (since I had just installed that version of Python and so Numpy wasn't installed yet). I installed numpy by typing pip install numpy and voilà ! The problem was solved and OpenCV imported correctly.

Hope this helps someone.

0
votes

In my case, I had to install an older version of openCV (windows 10, Python 3.6.8)

pip install opencv-python==3.3.0.9
0
votes

This error can be caused by missing the following dll enter image description here

To have this dll install: https://www.microsoft.com/en-us/software-download/mediafeaturepack as already explained above

-3
votes

Install python using:

  • pip install opencv-python(It will take the latest version)

Make sure opencv-python is installed in path(\Python\Python36\Lib\site-packages), you will find cv2 folder over there.

To check the version of cv2: import cv2 print(cv2.__version__)