Gobot: Controlling LEDs connected to an Arduino over Firmata using your face (OpenCV)

face-leds.go

package main

import (
	"fmt"
	"log"
	"path"
	"path/filepath"
	"runtime"

	cv "github.com/hybridgroup/go-opencv/opencv"
	"github.com/hybridgroup/gobot"
	"github.com/hybridgroup/gobot-firmata"
	"github.com/hybridgroup/gobot-gpio"
	"github.com/hybridgroup/gobot-opencv"
)

func firstUSBModem() string {
	devices, err := filepath.Glob("/dev/tty.usbmodem*")

	if err != nil || len(devices) < 1 {
		log.Fatal("No USB modem found.")
	}

	return devices[0]
}

func main() {
	_, currentfile, _, _ := runtime.Caller(0)
	cascade := path.Join(path.Dir(currentfile), "haarcascade_frontalface_alt.xml")

	opencv := new(gobotOpencv.Opencv)
	opencv.Name = "opencv"

	camera := gobotOpencv.NewCamera(opencv)
	camera.Name = "camera"

	firmata := new(gobotFirmata.FirmataAdaptor)

	firmata.Name = "firmata"
	firmata.Port = firstUSBModem()

	green := gobotGPIO.NewLed(firmata)
	green.Pin = "11"

	red1 := gobotGPIO.NewLed(firmata)
	red1.Pin = "10"

	red2 := gobotGPIO.NewLed(firmata)
	red2.Pin = "9"

	red3 := gobotGPIO.NewLed(firmata)
	red3.Pin = "6"

	red4 := gobotGPIO.NewLed(firmata)
	red4.Pin = "5"

	red5 := gobotGPIO.NewLed(firmata)
	red5.Pin = "3"

	work := func() {
		gobot.On(camera.Events["Frame"], func(data interface{}) {
			i := data.(*cv.IplImage)
			faces := gobotOpencv.DetectFaces(cascade, i)

			if len(faces) > 0 {
				green.On()

				f := faces[0]
				w := f.Width()

				switch {
				case w < 250:
					fmt.Println("*")
					red1.On()
					red2.Off()
					red3.Off()
					red4.Off()
					red5.Off()
				case w > 250 && w < 350:
					fmt.Println("**")
					red1.On()
					red2.On()
					red3.Off()
					red4.Off()
					red5.Off()
				case w > 350 && w < 400:
					fmt.Println("***")
					red1.On()
					red2.On()
					red3.On()
					red4.Off()
					red5.Off()
				case w > 400 && w < 450:
					fmt.Println("****")
					red1.On()
					red2.On()
					red3.On()
					red4.On()
					red5.Off()
				case w > 450:
					fmt.Println("*****")
					red1.On()
					red2.On()
					red3.On()
					red4.On()
					red5.On()
				}
			} else {
				green.Off()

				red1.Off()
				red2.Off()
				red3.Off()
				red4.Off()
				red5.Off()
			}
		})
	}

	robot := gobot.Robot{
		Connections: []gobot.Connection{opencv, firmata},
		Devices:     []gobot.Device{camera},
		Work:        work,
	}

	robot.Start()
}