This application provides a web-based interface to control the focus of a webcam on a Raspberry pi. Very useful on e.g. OctoPrint, where autofocus is not desirable

The easiest way to build the application is to cross-compile it from a desktop PC

Go can very easily cross-compile to the Raspberry Pi and to build pi-focus you need to install the Go tools on your pc/mac:

https://golang.org/doc/install

To to build the application for the Raspberry Pi, clone the pi-focus files to your machine and in the pi-focus direcory use the following command:

env GOOS=linux GOARCH=arm GOARM=7 go build

When the compilation is done, you can transfer the application to your Pi using the deploy.sh script.

You will need to edit the deploy-script so that it uses the correct IP-address of your Pi

When you have done that, just enter the following command. It will ask for the password for the pi user on the Pi, which will be raspberry unless you have changed it.

./deploy.sh

Now you can ssh to your Pi and start the application:

./pi-focus

When the application is running, you can enter the url :1080 (if using octopi, try octopi.local:1080) in your browser and then control the focus of your camera.

To enable pi-focus to always run on your pi, a systemd definition is provided. You can activate it like this:

cd ~
sudo cp pi-focus.service /etc/systemd/system
sudo systemctl start pi-focus.service
sudo systemctl enable pi-focus

This will ensure that pi-focus always runs when you boot up your Pi.