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Can't find GpuMAT() functions in v4.2.0-dev compiled with python & CUDA

asked 2019-12-27 13:01:56 -0500

AstroBen gravatar image

updated 2019-12-27 14:06:41 -0500

I have "successfully" compiled OpenCV v4.2.0-dev with python bindings and CUDA support on my Windows 10 machine following the many directions available online. I say successfully because compilation didn't throw errors. However, when I try to run a cv2.cuda command, I get an error such as:


error                                     Traceback (most recent call last) <ipython-input-10-f4bd798fbe4a> in <module>
----> 1 q=cv2.cuda.resize(base,dsize=(100,100))

error: OpenCV(4.2.0-dev) C:\Users\M43259\Documents\python\opencv\modules\core\src\matrix_wrap.cpp:359: error: (-213:The function/feature is not implemented) getGpuMat is available only for cuda::GpuMat and cuda::HostMem in function 'cv::_InputArray::getGpuMat'

It turns out there is no python call available that has anything with GpuMAT in it. For example:


AttributeError                            Traceback (most recent call last) <ipython-input-11-c14055330a2d> in <module>
----> 1 cv2.cuda_GpuMAT()

AttributeError: module 'cv2' has no attribute 'cuda_GpuMAT'

I'm stumped. I can provide loads of files and details if anyone wants.

EDIT 1 -------

While I'm looking for relevant cmake outputs, here is the output from cv2.getBuildInformation()

General configuration for OpenCV 4.2.0-dev =====================================
  Version control:               4.2.0-1-g89d3f95a8e

  Extra modules:
    Location (extra):            C:/Users/M43259/Documents/python/opencv_contrib/modules
    Version control (extra):     4.2.0

    Timestamp:                   2019-12-26T17:26:27Z
    Host:                        Windows 10.0.16299 AMD64
    CMake:                       3.16.2
    CMake generator:             Visual Studio 15 2017
    CMake build tool:            C:/Program Files (x86)/Microsoft Visual Studio/2017/Professional/MSBuild/15.0/Bin/MSBuild.exe
    MSVC:                        1914

  CPU/HW features:
    Baseline:                    SSE SSE2 SSE3
      requested:                 SSE3
    Dispatched code generation:  SSE4_1 SSE4_2 FP16 AVX AVX2 AVX512_SKX
      requested:                 SSE4_1 SSE4_2 AVX FP16 AVX2 AVX512_SKX
      SSE4_1 (16 files):         + SSSE3 SSE4_1
      SSE4_2 (2 files):          + SSSE3 SSE4_1 POPCNT SSE4_2
      FP16 (1 files):            + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 AVX
      AVX (5 files):             + SSSE3 SSE4_1 POPCNT SSE4_2 AVX
      AVX2 (29 files):           + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 FMA3 AVX AVX2
      AVX512_SKX (6 files):      + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 FMA3 AVX AVX2 AVX_512F AVX512_COMMON AVX512_SKX

    Built as dynamic libs?:      YES
    C++ Compiler:                C:/Program Files (x86)/Microsoft Visual Studio/2017/Professional/VC/Tools/MSVC/14.14.26428/bin/Hostx86/x64/cl.exe  (ver 19.14.26430.0)
    C++ flags (Release):         /DWIN32 /D_WINDOWS /W4 /GR  /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi  /fp:precise     /EHa /wd4127 /wd4251 /wd4324 /wd4275 /wd4512 /wd4589 /MP8   /MD /O2 /Ob2 /DNDEBUG 
    C++ flags (Debug):           /DWIN32 /D_WINDOWS /W4 /GR  /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi  /fp:precise     /EHa /wd4127 /wd4251 /wd4324 /wd4275 /wd4512 /wd4589 /MP8   /MDd /Zi /Ob0 /Od /RTC1 
    C Compiler:                  C:/Program Files (x86)/Microsoft Visual Studio/2017/Professional/VC/Tools/MSVC/14.14.26428/bin/Hostx86/x64/cl.exe
    C flags (Release):           /DWIN32 /D_WINDOWS /W3  /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi  /fp:precise       /MP8    /MD /O2 /Ob2 /DNDEBUG 
    C flags (Debug):             /DWIN32 /D_WINDOWS /W3  /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi  /fp:precise       /MP8  /MDd /Zi /Ob0 /Od /RTC1 
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please append the cmake output to your question

(it seems, it did not properly pick up cuda components)

berak gravatar imageberak ( 2019-12-27 13:43:59 -0500 )edit

I quit the cmake.exe and VS2017 programs yesterday so I don't have those outputs on a screen. Do you have thoughts of what files on disk might be helpful instead? I did edit the question to include the getBuildInformation if that is helpful to start with?

AstroBen gravatar imageAstroBen ( 2019-12-27 14:07:55 -0500 )edit

That's strange, from your build info CUDA was picked up. Your GpuMat error is consistent with not having built with CUDA however I would expect your resize error to resemble the below

AttributeError: module 'cv2.cuda' has no attribute 'resize'

How did you install the python binary (cv2.cp37-win_amd64.pyd)? Did you manually copy it into the site-packages directory? Are other functions from cv2 working? Do you also have opencv installed through conda? If you didn't build with -DOPENCV_SKIP_PYTHON_LOADER=ON it may be worth deleting the site-packages/cv2 directory and manually copying cv2.cp37-win_amd64.pyd directly into site-packages. I guess

where opencv_world420.dll

shows the path to the dll built with CUDA and not one which you built previously without?

cudawarped gravatar imagecudawarped ( 2019-12-28 02:18:40 -0500 )edit

Does this help? Unfortunately, don't use key.



q=cv2.cuda.resize(base, (100,100))

or: dsize = 100, 100

supra56 gravatar imagesupra56 ( 2019-12-28 09:57:11 -0500 )edit

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answered 2019-12-28 12:57:20 -0500

updated 2019-12-28 13:11:31 -0500

Nice spot by @supra56. CUDA looks to be installed properly, you are just passing the wrong arguments and not using autocomplete for function names.

GpuMat should be working fine, you just have a typo (always best to use autocomplete), it should be




I think the second problem is that you are passing a numpy array instead of a GpuMat to resize. Some cuda functions may accept numpy arrays but I would advise against it and always pass GpuMat unless the function explicitly requires a numpy array. All that said all the below should work

cuMat = cv2.cuda_GpuMat(npMat)
q = cv2.cuda.resize(cuMat,dsize=(100,100))




q = cv2.cuda_GpuMat((100,100),cuMat.type())

I would suggest the last one because it avoids allocating the return matrix on each invocation, so it will be much much faster, which you can verify by comparing

%timeit cv2.cuda.resize(cuMat,(100,100))
%timeit cv2.cuda.resize(cuMat,(100,100),q)
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@cudawarped. THANKS!. I just dowloaded OpenCV 4.2.0 Unfortunately, haven't attempted yet. I will test it.

supra56 gravatar imagesupra56 ( 2019-12-28 16:02:36 -0500 )edit

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Asked: 2019-12-27 13:01:56 -0500

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Last updated: Dec 28 '19