Devendor OpenCvSharp

[colombod]

Version 4.5.x of OpenCVSharp is available and that exposes OpenCV 4.5.0 functionalities

• build the opencv native runtimes for pi-top[4] from version 4.5.x
• add nuget package definition for 4.5.x runtime
• update readme file to contain the build instructions for the native dependencies

[m-roberts]

I will speak to @jcapona about this as he did the first compilation.

[m-roberts]

Tackling the first part of this - I will merge in 4.5.0 as we have it currently. I will need help with the NuGet packaging after that.

[colombod]

Tackling the first part of this - I will merge in 4.5.0 as we have it currently. I will need help with the NuGet packaging after that.

Sounds good and I can help with that but next turn of the crank is to use a docker file to pull in opencv specific version, build what we need and run a script to generate the nuget spec required and finally pack the stuff in a package we can get and push to nuget (manually build and push)

[angusjfw]

Is there a particular reason to use a Docker file for this script?

As we are compiling for arm, it will be easiest to do this on a rpi, rather than cross-compile. Compiling opencv on the pi generally uses pretty much all it's memory, requiring extra swap, and running docker will make that worse.

It sounds like we only need to do this process once, and if we need to start afresh Mike probably has some unused pi-topOS SD cards around 😛

[m-roberts]

I can't see why we need to worry about that now. If there's a NuGet package with 4.5.0, we have addressed the issues that are in front of us.

[m-roberts]

I have a PR open #12 which adds 4.5.0 OpenCVSharp. Can somebody confirm that I have done this correctly?
What needs to happen next? I am unfamiliar with how to do the NuGet packaging part.

[colombod]

Not having the native dependencies available via nuget will affect the ability of pi-top user to run the app on their machine

[m-roberts]

Not sure how to act on that. Can you explain what needs to happen?

[colombod]

We need automation to

• download and compile native depedencies on pi-top
• modifies unspecified template according to version and files to pack
• packs the binaries into nugget
• cleans the environment post build

We need this process every time we have a dependency that

• is not present on nugget
• needs to support side by side versions
• is not needed unless a customer decides to use it in the application being launched

@paulmey has some suggestions we should take into account

[m-roberts]

Latest released version of OpenCVSharp is being built daily in a GitHub Action here: https://github.com/pi-top/opencvsharp-arm. There are still some things that need to be done there

[m-roberts]

OpenCVSharp should now be available from Nuget: https://www.nuget.org/packages/OpenCvSharp4.runtime.linux-arm/4.5.2.20210507

[colombod]

you will still need the 4.5.2 binaries for the raspian as of now the repo contains only 4.5.0 in runtimes\opencvsharp\ the binaries of opencv4.5.2 still need to be done

[m-roberts]

• Build latest OpenCV for Raspberry Pi in new repo
• Produce GitHub Release for 4.5.2
• Update libs/: drop OpenCV zip from setup script steps; download and install from latest Release instead