Add docker files and build instructions

[Granjow]

Related: #3

[Granjow]

@JJones780 – do you want to review this and check if the docker build works for you if you follow the readme?

[JJones780]

My internet isn't the fastest so I don't use docker very often.
My Docker didn't recognize -name . I had to use -t instead
after running the second docker command I'm getting an error
"/bin/sh: 0: cannot open ./build.sh: No such file"

I'm out of practice with Docker... so it isn't obvious to me how the v3d-flow source is supposed be accessed from the running docker instance?

[Granjow]

Thanks for testing! Right, the -name was wrong indeed.

Did you use the volume mount (-v …)? That is the command which mounts your current directory (which should be the repo root) into the docker container, and also how the compiled binary is copied back.

[JJones780]

Yes, used the command as written in the Readme with the -v option.
I don't see any build.sh script in the repo root.
I didn't do the submodule update or any steps in the section above... I assume that's what the build.sh will do once I get it?

[Granjow]

@JJones780 My bad – It was ignored because of the .gitignore file. Now it should work!

No, the build.sh does not update submodules, it only runs cmake/make :)

[JJones780]

I built using docker successfully.

tried running it and got this:
./slowmoFlowBuilder: error while loading shared libraries: libjpeg.so.8: cannot open shared object file: No such file or directory
whereas running the one I compiled without docker had no problems.

I hope you can keep the docker image small... it's practical.

[Granjow]

Thanks for testing. What OS are you on atm.? You need the same as in the docker image, otherwise it may fail to find shared libraries.

[JJones780]

I'm running Devuan daedalus which should have the same libjpeg as Debian 12 ( Bookworm).
I've got libjpeg62-turbo-dev which solves this issue in similar cases but not here.

A common solution mention on the 'net is to create a symlink:
sudo ln -s /usr/lib/x86_64-linux-gnu/libjpeg.so.62 /usr/lib/x86_64-linux-gnu/libjpeg.so.8

which still gets an error:
./slowmoFlowBuilder: /usr/lib/x86_64-linux-gnu/libjpeg.so.8: version `LIBJPEG_8.0' not found (required by ./slowmoFlowBuilder)