Installation on Windows 10 about ffcv

[GuillaumeLeclerc]

Hello,

Unfortunately none of us own a windows machine so it will be hard for us to help troubleshoot this. We did not intend to support Windows in the first place.

We use pkg-config to find the paths to the libturbojpeg and opencv libraries. You could craft your own setup.py with the correct paths to these libraries.

Hope it helps :/

[kynk94]

I built ffcv successfully with my Windows 10 PC
This is the installation process I did.

Install opencv (https://opencv.org/releases/)
After install opencv, move to C:/opencv

Install libjpeg-turbo (https://sourceforge.net/projects/libjpeg-turbo/)
download libjpeg-turbo-x.x.x-vc64.exe, not gcc64

Install pthread (https://www.sourceware.org/pthreads-win32/)
I downloaded pthreads-w32-2-9-1-release.zip
After unzip, rename Pre-build.2 folder to pthread and move to C:/pthread

And install mingw.

We need to configure .pc file of above packages to find them with pkg-config.
pkg-config .pc files path: C:/msys64/mingw64/lib/pkgconfig

create and paste below files to pkg-config path

# opencv4.pc 

prefix=c:/opencv/build
exec_prefix=c:/opencv/build
libdir=c:/opencv/build/x64/vc15/lib
includedir=c:/opencv/build/include

Name: OpenCV
Description: Open Source Computer Vision Library
Version: 4.5.5
Libs: -Lc:/opencv/build/x64/vc15/lib -lopencv_world455
Cflags: -Ic:/opencv/build/include

# libturbojpeg.pc

prefix=c:/libjpeg-turbo64
exec_prefix=c:/libjpeg-turbo64
libdir=c:/libjpeg-turbo64/lib
includedir=c:/libjpeg-turbo64/include

Name: libturbojpeg
Description: A SIMD-accelerated JPEG codec that provides the TurboJPEG API
Version: 2.1.2
Libs: -Lc:/libjpeg-turbo64/lib -lturbojpeg
Cflags: -Ic:/libjpeg-turbo64/include

# pthread.pc

Name: Pthread
Description: Pthread
Version: VC2
Libs: -LC:/pthread/lib/x64 -lpthreadVC2
Cflags: -IC:/pthread/include

Now pkg-config can recognize opencv4, libturbojpeg, pthread.

In setup.py, add extension_kwargs = pkgconfig('pthread', extension_kwargs)
and mute extension_kwargs['libraries'].extend(['pthread']), like below.

# setup.py
...
extension_kwargs = pkgconfig('opencv4', extension_kwargs)
extension_kwargs = pkgconfig('libturbojpeg', extension_kwargs)
extension_kwargs = pkgconfig('pthread', extension_kwargs)  # add this line.

# extension_kwargs['libraries'].extend(['pthread'])  # mute this line.
...

In libffcv/libffcv.cpp remove dunder from dunder uint in imdecode

// libffcv/libffcv.cpp
    int imdecode(unsigned char *input_buffer, uint64_t input_size,
                 uint32_t source_height, uint32_t source_width,
                 unsigned char *output_buffer,
                 uint32_t crop_height, uint32_t crop_width,
                 uint32_t offset_x, uint32_t offset_y,
                 uint32_t scale_num, uint32_t scale_denom,
                 bool enable_crop,
                 bool hflip)

Finally, can build ffcv by following command without error.

python setup.py bdist_wheel

However, I haven't checked the operation of ffcv on my Windows PC yet.

[GuillaumeLeclerc]

That's amazing. Feel tree to make a pull request if you are fine making this available to other users. In the meantime I will close this issue.