Opencv compile and call GPU version

1、 Install well cuda drive

        May refer to CUDA Environment building _ima_zhan The blog of -CSDN Blog _cuda Environment building

2、 download opencv 3.11 Source code and lib

        On the official website release The download of each version can be found on the page

         Releases - OpenCV

3、 download cmake 3.23.2, Baidu can go to the official website to download

4、 open cmake, Select source file as opencv3.11 Source code , The compilation directory is newly created opencv311_build

      Click on Configure, Make the following configuration in the configuration window ：

      stay WITH Choose from WITH_CUDA,WITH_NVCUVID.

      stay BUILD Choose BUILD_opencv_world Compile the file into a dll, It's really convenient to quote , But the file is a little big , I finally have 200 Multi megabit .

      Configure You can click again if you encounter an error in Configure Have a try , Other mistakes can be found in 5 The solution in .

        complete Configure Then click Generate Build project , And then click OpenProject Open the project .

5、 Several problems encountered during compilation

      1、 First choose cuda, Click on Configure You can't see it until the button runs once cuda The option to , stay CUDA_ARCH_BIN Configuring the version you need in can really improve the following vs Compilation speed in . Other acceleration methods , It's useful to find some in others' blogs , Direct reference  win10 compile opencv4.5.0 （gpu edition ）_Mr.Q The blog of -CSDN Blog _win install opencv

      2、 File cannot be downloaded

            ffmpegedll There are other files that cannot be downloaded automatically , You can download and replace .cache file , The main downloaded files are changed to and .cache The same name in . The download connection can be viewed in the error prompt file , stay build The folder CMakeDownloadLog.txt There are all the ways .

      3、 Compile time cuda Options are automatically selected , If all are selected in vs Errors will be reported when compiling . This is what happened to me , The detailed reason has not been checked .

6、 Errors encountered in the use of compiled

      After successful compilation, a mfc Engineering to test opencv_world3411d.dll Call to , Encountered several errors

      error 1：

                  Put... In the source file include Folder added to

                 base.hpp Middle tip , Error in the following figure

      In operation engineering Install, Will be in  opencv311_build Produced under the catalogue install Catalog , Among them is include The folder contains the header files that need to be referenced . Add this folder to C++ The contents of , The specific operation is as follows ：

      error 2： Compile the prompt “ Unresolved external symbols private:void _cdecl cv::String::deallocate(void)"

      Need to put install In the catalog x64（ Because I use x64） In the catalog vc16/lib Under the opencv_world3411d.lib Add to project OpenCvCamera Of lib In the list , The specific operation is

      First of all, will install In the catalog x64/vc16/lib Directory added to vc++ The Library Directory of , as follows

    Then add opencv_world3411d.lib, as follows