ryoppippi / zigcv

zig bindings for OpenCV4

ZIGCV

The ZIGCV library provides Zig language bindings for the OpenCV 4 computer vision library.

The ZIGCV library supports the head/master of zig and OpenCV (v4.6.0) on Linux, macOS, and Windows.

Caution

Still under development, so the zig APIs will be dynamically changed.

You can use const c_api = @import("zigcv").c_api; to call c bindings directly.
This C-API is currently fixed.

How to execute

Use your own package manager

At first, install openCV 4.6. (maybe you can read how to install from here).
Then:

git clone --recursive https://github.com/ryoppippi/zigcv
cd zigcv
zig build

Currently this repo works with zig 0.11.0, so make sure you have it installed. We are working on updating to zig 0.12.0.

Use devbox

We also provide a devbox config to manage dependencies and build environments.

git clone --recursive https://github.com/zigcv
cd zigcv
devbox init

Checkout devbox.json for more details.

Demos

you can build some demos. For example:

zig build examples
./zig-out/bin/face_detection 0

Or you can run the demo with the following command:

devbox run build examples
./zig-out/bin/face_detection 0

You can see the full demo list by zig build --help.

Technical restrictions

Due to zig being a relatively new language it does not have full C ABI support at the moment.
For use that mainly means we can't use any functions that return structs that are less than 16 bytes large on x86, and passing structs to any functions may cause memory error on arm.

License

MIT

Author

Ryotaro "Justin" Kimura (a.k.a. ryoppippi)

zigcv's Issues

update to 0.11.0

dnn detection demo does not work

libc++abi: terminating with uncaught exception of type cv::Exception: OpenCV(4.6.0) /opt/homebrew/opt/opencv/include/opencv4/opencv2/core/mat.inl.hpp:896: error: (-215:Assertion failed) dims <= 2 in function 'at'

CI Fails

currently, we run ci on macos.
However, it is too slow to install dependencies with homebrew

Change MatType to packed struct

#4
With packed struct, type and channel can be set intuitively. On the other hand, we need to write more. On the other hand, it increases the amount of description, and since it is a destructive change, there is room for consideration on whether to introduce it or not.

failed to build with ubuntu

Because opencv on nix/apt is built with gcc, it is not compatible with zig.

Solution:

• Create nix overlay to build opencv by zigcv or clang

Related Issues:

• ziglang/zig#13018

Face_detection Example does not work on M1 mac

libc++abi: terminating with uncaught exception of type cv::Exception: OpenCV(4.6.0) /tmp/opencv-20220814-85292-f59axv/opencv-4.6.0/modules/imgproc/src/drawing.cpp:1841: error: (-215:Assertion failed) thickness <= MAX_THICKNESS in function 'rectangle'

The arguments are not passed properly.

Probably this is because of ziglang/zig#1481

update to zig 0.12.0

update to gocv 0.34.0

update to gocv 0.32.1

does not work imEncodeWithParams on M1 Mac

https://github.com/ryoppippi/zigcv/blob/619e465671366e24862bab975ad8c6641e75743a/src/imgcodecs.zig#L233-L235

When executing this, it crashes

Test for Core

It takes a lot of time...

I have ported most of the tests in gocv, but have done very little from core_test.go.

WASM support

• Build Opencv.js with Zig Compiler

• Build Opencv WASM directly from zigcv

create zig/zon file for project

update to the latest gocv

make monorepo

create monorepo with zig.zon
This is the part of #29

update gocv to 0.35.0 (opencv 4.8.1)

Apply packed structs strategy

https://devlog.hexops.com/2022/packed-structs-in-zig/

build failed

Hmm....

update to gocv 0.36.0 (opencv 4.9.0)

update gocv to 0.34.0 ( opencv 4.8.0)

remove docker & use nix-flake or devbox

because the build environement is hard to maintain, I'd like to take advantage of nix.

pin zig version to 0.10.1

Create zig binding auto generator from header file

Currently, zigcv reads and uses gocv header files, but this does not allow function name and type completion on the editor. ralib-zig would like to generate zig code from c header files, like ralib-zig.

There are two options

• auto-generation from go files
• auto-generation from c header files

allocate opencv objects by zig allocators instead of c malloc

Example https://github.com/michal-z/zig-gamedev/blob/940c188fa7/libs/zstbi/src/zstbi.zig

update to zig 0.11.0

I'm back!

Hello!

I had archived this project due to lack of enthusiasm, but decided to maintain it again.

This is because zig 0.12.0 is now available and we have also solved the build method.

update gocv to 0.33.0

zigcv built failed

zig version: 0.10.0-dev.4476+0f0076666

mingw64 version: 8.1.0

zig build log:
build.txt

Arm docker build

Goal to opencv 4.9.0

There are several tasks:

• #33
• #32
• #29
• #39
• #42
• #43
• #44
• #45
• #36
• #37
• #38
• #46
• #47

CStrings is not stable

https://github.com/ryoppippi/zigcv/blob/a436dc7e392b66a0841c046436cabba9fe4d86cd/src/objdetect.zig#L268-L310

https://github.com/ryoppippi/zigcv/blob/a436dc7e392b66a0841c046436cabba9fe4d86cd/src/objdetect.zig#L485-L487

Returned text will be wired.
This is because of passing structs

Version:
v0.10.0-dev.3761+5bb8c0369

update to gocv 0.32.0

update to gocv 0.33.0

update to gocv 0.36.1