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

[burhankhanlodhy]

Recently I updated my raspy library and it started to give me an error stating "ImportError: DLL load failed: The specified module could not be found". I removed the latest update and installed the older one and its working like a charm. Are there some new dependencies with the new version that needs to be installed as well or is it a bug?

All I wrote is import rawpy.enhance and it gave me that error in the newer update.

[letmaik]

Can you check if this happens with the pre-release v0.14.0a1 as well?

[letmaik]

Just bumped into the same when installing the wheel on a semi-fresh conda env.

Using gflags and WinDbg the error shows as Unable to load DLL: "zlib.dll" Parent Module: "...\rawpy\raw_r.dll". It looks like jpeg is linked in statically but zlib is a shared library.

To confirm that, let's extract one of the Windows packages in https://anaconda.org/anaconda/jpeg:

Library/
  lib/
    libjpeg.lib
    jpeg.lib (bigger file -> static library)
  bin/
    libjpeg.dll

The libraw CMake build has found Library/lib/jpeg.lib which is the static library and everything is fine.

Now the same for https://anaconda.org/anaconda/zlib:

Library/
  lib/
    zlibstatic.lib
    zlib.lib
    zdll.lib
    z.lib
  bin/
    zlib.dll

The libraw CMake build has found Library/lib/z.lib which is the dynamic library. Changing that to zlibstatic.lib should solve the issue. Bundling zlib.dll in the rawpy package is not an option as this will lead to DLL hell and potentially interfere with other packages.

EDIT: Convincing CMake to find the static library may be more tricky than I thought without manually specifying the full path to it: https://gitlab.kitware.com/cmake/cmake/issues/18029#note_685314

[letmaik]

Fixed in 34c9d07815a66725beda0044703f1fee63055952.