Import PySpin in Conda: fails to find mkl_intel_thread.dll

Question

I'm using the PySpin api for a Point Grey camera in Anaconda. The api is a Python wrapper for a C++ library called Spinnaker (https://www.ptgrey.com/spinnaker-sdk).

When I import within Spyder (import PySpin), things work fine (note I start Spyder from the Conda prompt in the environment where everything is installed). Unfortunately running the import from the conda prompt instead of Spyder (python foo.py where foo.py contains import PySpin) yields:

Intel MKL FATAL ERROR: Cannot load mkl_intel_thread.dll.

The ordinal 242 could not be located in the dynamic link library C:\Anaconda3\Library\bin\mkl_intel_thread.dll

Note I installed Spinnaker (PySpin) from a wheel at the anaconda prompt:

pip install spinnaker_python-1.20.0.15-cp36-cp36m-win_amd64.whl

A bunch of places online it says to find the following files in C:\Windows\System32 and rename them or delete them:

mkl_core.dll
mkl_def.dll
mkl_intel_thread.dll

Those files are not present on my machine, so that seems to not be the problem in my case.

For instance here they mention that solution:
The ordinal 242 could not be located in the dynamic link library Anaconda3\Library\bin\mkl_intel_thread.dll

Answer 1

When I first import numpy and the import PySpin, then it works for me.

import numpy as np # must be imported first
import PySpin

system = PySpin.System.GetInstance()
version = system.GetLibraryVersion()
print('Library version: %d.%d.%d.%d' % (version.major, version.minor, version.type, version.build))
# Library version: 1.20.0.15

I am using Python 3.5 under Windows 10 with Miniconda.

Answer 2

Solution recommended by Point Grey

From the developers at Point Grey, who I emailed about this issue and they were aware of it. They suggested removing the numpy that is installed with conda and reinstall it with pip. That is:

conda uninstall numpy
pip install numpy

Note while this worked, I can't guarantee it will scale well within complex projects that include other dependencies.

Update: this worked for a day or so, but in my hands it stopped working when I added other dependencies/updates (in particular OpenCV). However, maybe other people will have better luck with this solution so I'll leave it here.

---

Second Solution

If you are having trouble with the other solutions, maybe give this a shot it worked for me: run the code from ipython launched from the conda prompt, and then run from conda again:

ipythyon
%run foo.py  #script containing import PySpin
exit()

It worked there, which is not surprising (this is basically what Spyder does). Strangely, back in the conda prompt I tried running the program again:

python foo.py

And this time it worked. So, it was not working before I did it in ipython, and now it is working.

Frankly I have no idea why this fixed the problem, but it did. \_(ツ)_/

I'm leaving these solutions here, but frankly I would try importing numpy before PySpin, as in the accepted answer. It's just easier and less disruptive.

Answer 3

The issue is caused by file libiomp5md.dll included in the spinnaker_python wheel being incompatible with Anaconda distribution. Simply removing or renaming this file will result the default Anaconda version of the file to be loaded instead.

Execute the following command from the Anaconda prompt to fix the issue. If Anaconda is installed for all users, you need Administrator version of Anaconda prompt.

move %CONDA_PREFIX%\Lib\site-packages\PySpin\libiomp5md.dll %CONDA_PREFIX%\Lib\site-packages\PySpin\libiomp5md.bak