Hi everyone, I need your support to better understand the usage of OpenBLAS in OpenCV.
Project Description
I have a project in which I use OpenCV as a dependency.
The library is downloaded and compiled using vcpkg, CMake and MSVC.
I would like to add OpenBLAS as a dependency of my project.
I read online that OpenCV has support for the usage of a BLAS/LAPACK library, but I cannot find any detailed information in the documentation.
VCPKG Integration
In the vcpkg.json of my project I enabled the OpenCV’s lapack feature, which I suppose enables the LAPACK/BLAS interface.
I also added OpenBLAS as a dependency.
After performing this steps, I notice a new print in the vcpkg log during configuration
-- Running vcpkg install - done
-- Using VCPKG FindLAPACK from package 'lapack-reference'
-- A library with LAPACK API found.
From this, I suppose that OpenCV has found the OpenBLAS dependency.
Printing the build information using cv::getBuildInformation() I obtain the following
General configuration for OpenCV 4.6.0 =====================================
Version control: unknown
Platform:
Timestamp: 2024-01-10T14:28:17Z
Host: Windows 10.0.22621 AMD64
CMake: 3.27.4
CMake generator: Ninja
CMake build tool: C:/lib/vcpkg/downloads/tools/ninja/1.10.2-windows/ninja.exe
MSVC: 1916
Configuration: Release
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 (14 files): + SSSE3 SSE4_1
SSE4_2 (1 files): + SSSE3 SSE4_1 POPCNT SSE4_2
FP16 (0 files): + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 AVX
AVX (4 files): + SSSE3 SSE4_1 POPCNT SSE4_2 AVX
AVX2 (29 files): + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 FMA3 AVX AVX2
AVX512_SKX (5 files): + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 FMA3 AVX AVX2 AVX_512F AVX512_COMMON AVX512_SKX
C/C++:
Built as dynamic libs?: NO
C++ standard: 11
C++ Compiler: C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/MSVC/14.16.27023/bin/HostX64/x64/cl.exe (ver 19.16.27051.0)
C++ flags (Release): /nologo /DWIN32 /D_WINDOWS /W4 /utf-8 /GR /MP /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /fp:precise /FS /EHa /wd4127 /wd4251 /wd4324 /wd4275 /wd4512 /wd4589 /MT /O2 /Oi /Gy /DNDEBUG /Z7
C++ flags (Debug): /nologo /DWIN32 /D_WINDOWS /W4 /utf-8 /GR /MP /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /fp:precise /FS /EHa /wd4127 /wd4251 /wd4324 /wd4275 /wd4512 /wd4589 /D_DEBUG /MTd /Z7 /Ob0 /Od /RTC1
C Compiler: C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/MSVC/14.16.27023/bin/HostX64/x64/cl.exe
C flags (Release): /nologo /DWIN32 /D_WINDOWS /W3 /utf-8 /MP /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /fp:precise /FS /MT /O2 /Oi /Gy /DNDEBUG /Z7
C flags (Debug): /nologo /DWIN32 /D_WINDOWS /W3 /utf-8 /MP /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /fp:precise /FS /D_DEBUG /MTd /Z7 /Ob0 /Od /RTC1
Linker flags (Release): /machine:x64 /NODEFAULTLIB:atlthunk.lib /nologo /DEBUG /INCREMENTAL:NO /OPT:REF /OPT:ICF /debug /NODEFAULTLIB:libcmtd.lib /NODEFAULTLIB:libcpmtd.lib /NODEFAULTLIB:msvcrtd.lib
Linker flags (Debug): /machine:x64 /NODEFAULTLIB:atlthunk.lib /nologo /debug /INCREMENTAL /NODEFAULTLIB:libcmt.lib /NODEFAULTLIB:libcpmt.lib /NODEFAULTLIB:msvcrt.lib
ccache: NO
Precompiled headers: NO
Extra dependencies: protobuf::libprotobuf comctl32 gdi32 ole32 setupapi ws2_32 quirc::quirc
3rdparty dependencies:
OpenCV modules:
To be built: calib3d core dnn features2d flann highgui imgcodecs imgproc ml objdetect photo stitching video videoio world
Disabled: -
Disabled by dependency: -
Unavailable: gapi java python2 python2 python3 ts
Applications: -
Documentation: NO
Non-free algorithms: NO
Windows RT support: NO
GUI:
Win32 UI: YES
Media I/O:
ZLib: optimized C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/lib/zlib.lib debug C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/debug/lib/zlibd.lib (ver 1.2.13)
JPEG: optimized C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/lib/jpeg.lib debug C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/debug/lib/jpeg.lib (ver 62)
WEBP: (ver 1.2.4)
PNG: optimized C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/lib/libpng16.lib debug C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/debug/lib/libpng16d.lib (ver 1.6.39)
TIFF: optimized C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/lib/tiff.lib debug C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/debug/lib/tiffd.lib (ver 42 / 4.4.0)
HDR: YES
SUNRASTER: YES
PXM: YES
PFM: YES
Video I/O:
DirectShow: YES
Media Foundation: YES
DXVA: YES
Parallel framework: Concurrency
Trace: YES (built-in)
Other third-party libraries:
Lapack: NO
Custom HAL: NO
Protobuf: optimized C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/lib/libprotobuf.lib debug C:/Users/***/Documents/projects/***/build/release/vcpkg_installed/x64-windows-static-v141/debug/lib/libprotobufd.lib version (3.21.8.0)
OpenCL: YES (NVD3D11)
Include path: C:/lib/vcpkg/buildtrees/opencv4/src/4.6.0-9a95a1b699.clean/3rdparty/include/opencl/1.2
Link libraries: Dynamic load
Python (for build): NO
Install to: C:/lib/vcpkg/packages/opencv4_x64-windows-static-v141
-----------------------------------------------------------------
Questions
- From the
Other third-party libraries:I can see that a path forLapackis not provided. Is this correct? - How can I be sure that OpenCV has detected the OpenBLAS library?
- Is there any point in the documentation where the integration with a BLAS library is documented? How can I know which functions are affected by the usage of a BLAS library?
Thanks in advance for your help!