fix

Author: shimat

.gitignore

@@ -124,6 +124,7 @@ UpgradeLog*.XML
 /opencv_artifacts/
 /tesseract_artifacts/
 /vcpkg_installed/
+/src/build/
 /opencv_files
 /test/OpenCvSharp.Tests/dll/x64/*.dll
 /test/OpenCvSharp.Tests/dll/x86/*.dll

README.md

@@ -218,7 +218,11 @@ https://github.com/shimat?tab=packages
    git submodule update --init --recursive
    ```
 
-2. Build OpenCV from source (Tesseract is automatically installed via vcpkg):
+2. Build OpenCV from source (Tesseract and other native dependencies are automatically installed via vcpkg):
+   ```powershell
+   # Install vcpkg dependencies (only needed once, or after vcpkg.json changes)
+   C:\vcpkg\vcpkg.exe install --triplet x64-windows-static --overlay-triplets cmake\triplets --x-install-root vcpkg_installed
+   ```
    ```powershell
    .\build_opencv_windows.ps1
    # Use -Jobs N to control parallel build (default: 4)
@@ -229,10 +233,11 @@ https://github.com/shimat?tab=packages
 3. Build the native wrapper `OpenCvSharpExtern`:
    ```powershell
    cmake -S src -B src\build -G "Visual Studio 17 2022" -A x64 `
-         -D CMAKE_PREFIX_PATH="opencv_artifacts" `
+         -D "CMAKE_PREFIX_PATH=$PWD\opencv_artifacts" `
          -D CMAKE_TOOLCHAIN_FILE="C:\vcpkg\scripts\buildsystems\vcpkg.cmake" `
          -D VCPKG_TARGET_TRIPLET=x64-windows-static `
-         -D VCPKG_INSTALLED_DIR="vcpkg_installed"
+         -D "VCPKG_INSTALLED_DIR=$PWD\vcpkg_installed" `
+         -D "VCPKG_OVERLAY_TRIPLETS=$PWD\cmake\triplets"
    cmake --build src\build --config Release
    ```
 
@@ -241,6 +246,8 @@ https://github.com/shimat?tab=packages
    ```powershell
    dotnet build src/OpenCvSharp/OpenCvSharp.csproj -c Release
    ```
+   > **Note on the native DLL:** Step 3 automatically copies `OpenCvSharpExtern.dll` into `test/OpenCvSharp.Tests/` as a post-build step, so `dotnet test` works out of the box.
+   > For your own application, either add `src\build\OpenCvSharpExtern\Release` to `PATH`, or copy `OpenCvSharpExtern.dll` alongside your app's output directory.
 
 ### Ubuntu
 - Build OpenCV with opencv_contrib: https://docs.opencv.org/4.x/d7/d9f/tutorial_linux_install.html

build_opencv_windows.ps1

@@ -133,9 +133,9 @@ Write-Host "Done. OpenCV installed to: $installDir"
 Write-Host ""
 Write-Host "Next step — configure and build OpenCvSharpExtern:"
 Write-Host "  cmake -S src -B src\build -G `"$vsGenerator`" -A x64 ``"
-Write-Host "        -D CMAKE_PREFIX_PATH=`"$installDir`" ``"
+Write-Host "        -D `"CMAKE_PREFIX_PATH=`$PWD\opencv_artifacts`" ``"
 Write-Host "        -D CMAKE_TOOLCHAIN_FILE=`"$vcpkgToolchain`" ``"
 Write-Host "        -D VCPKG_TARGET_TRIPLET=x64-windows-static ``"
-Write-Host "        -D VCPKG_INSTALLED_DIR=`"$vcpkgInstalledDir`" ``"
-Write-Host "        -D VCPKG_OVERLAY_TRIPLETS=`"$RepoRoot/cmake/triplets`""
+Write-Host "        -D `"VCPKG_INSTALLED_DIR=`$PWD\vcpkg_installed`" ``"
+Write-Host "        -D `"VCPKG_OVERLAY_TRIPLETS=`$PWD\cmake\triplets`""
 Write-Host "  cmake --build src\build --config Release"

cmake/opencv_build_options.cmake

@@ -45,5 +45,14 @@ set(BUILD_opencv_wechat_qrcode             ON  CACHE BOOL "" FORCE)
 set(WITH_GSTREAMER OFF CACHE BOOL "" FORCE)
 set(WITH_ADE       OFF CACHE BOOL "" FORCE)
 
-# Use a flat install layout (avoids x64/vc17/ subdirectories; libs go to staticlib/)
-set(OpenCV_INSTALL_BINARIES_PREFIX "" CACHE STRING "" FORCE)
+# On Windows, disable bundled 3rd-party lib builds so OpenCV uses the vcpkg-provided
+# versions instead. This ensures OpenCVModules.cmake references paths in
+# vcpkg_installed/ (which exist) rather than uninstalled paths in opencv_artifacts/.
+# These packages are guaranteed to be present via vcpkg.json dependencies.
+if(WIN32)
+  set(BUILD_ZLIB  OFF CACHE BOOL "" FORCE)
+  set(BUILD_TIFF  OFF CACHE BOOL "" FORCE)
+  set(BUILD_JPEG  OFF CACHE BOOL "" FORCE)
+  set(BUILD_PNG   OFF CACHE BOOL "" FORCE)
+  set(BUILD_WEBP  OFF CACHE BOOL "" FORCE)
+endif()

src/OpenCvSharpExtern/CMakeLists.txt

@@ -17,28 +17,26 @@ if(APPLE)
 endif()
 
 # On Windows, OpenCV is built as a static library; tell the Windows Pack config to look for static libs.
+# Also force /MT (static CRT) to match OpenCV's build configuration, and enable /MP for parallel compilation.
 if(WIN32)
 	set(OpenCV_STATIC ON)
+	set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
+	add_compile_options($<$<CXX_COMPILER_ID:MSVC>:/MP>)
 endif()
 
 find_package(OpenCV REQUIRED)
 
 # iconv support isn't automatic on some systems
 find_package(Iconv QUIET)
-if(Iconv_FOUND)
-  ocv_target_link_libraries(${the_module} Iconv::Iconv)
-else()
-  ocv_target_compile_definitions(${the_module} PRIVATE "NO_ICONV=1")
+if(NOT Iconv_FOUND)
+  add_compile_definitions(NO_ICONV=1)
 endif()
 
 if(OpenCV_FOUND)
 	include_directories(${OpenCV_INCLUDE_DIRS})
 	#set(LIBS ${LIBS} ${OpenCV_LIBRARIES})
 
 	if(CMAKE_GENERATOR MATCHES "Visual Studio")
-		set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} /MT")
-		set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} /MTd")
-		
 		set(CMAKE_CXX_STANDARD_LIBRARIES "${CMAKE_CXX_STANDARD_LIBRARIES} kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib")
 	endif()
 
@@ -50,6 +48,10 @@ if(OpenCV_FOUND)
 		target_link_libraries(OpenCvSharpExtern ${OpenCV_LIBRARIES})
 	endif()
 
+	if(Iconv_FOUND)
+		target_link_libraries(OpenCvSharpExtern Iconv::Iconv)
+	endif()
+
 	# Link Tesseract on Windows (using vcpkg-style prefix via CMAKE_PREFIX_PATH)
 	if(WIN32 AND NOT EMSCRIPTEN)
 		find_package(Tesseract QUIET)

vcpkg.json

@@ -1,9 +1,11 @@
 {
   "dependencies": [
-    {
-      "name": "tesseract",
-      "platform": "windows"
-    }
+    {"name": "tesseract",       "platform": "windows"},
+    {"name": "zlib",            "platform": "windows"},
+    {"name": "libpng",          "platform": "windows"},
+    {"name": "libjpeg-turbo",   "platform": "windows"},
+    {"name": "tiff",            "platform": "windows"},
+    {"name": "libwebp",         "platform": "windows"}
   ],
   "builtin-baseline": "1e199d32ad53aab1defda61ce41c380302e3f95c"
 }