Added gocv experimental code with testing files

exp/gocv-exp/main.go

@@ -0,0 +1,117 @@
+// What it does:
+//
+// This example detects motion using a delta threshold from the first frame,
+// and then finds contours to determine where the object is located.
+//
+// Very loosely based on Adrian Rosebrock code located at:
+// http://www.pyimagesearch.com/2015/06/01/home-surveillance-and-motion-detection-with-the-raspberry-pi-python-and-opencv/
+
+package main
+
+import (
+	"fmt"
+	"image"
+	"image/color"
+	"os"
+	"strconv"
+	"time"
+
+	"gocv.io/x/gocv"
+)
+
+const MinimumArea = 1000
+
+func main() {
+	if len(os.Args) < 2 {
+		fmt.Println("How to run:\n\tmotion-detect [camera ID]")
+		return
+	}
+
+	// parse args
+	deviceID := os.Args[1]
+	minArea, _ := strconv.Atoi(os.Args[2])
+
+	webcam, err := gocv.OpenVideoCapture(deviceID)
+	if err != nil {
+		fmt.Printf("Error opening video capture device: %v\n", deviceID)
+		return
+	}
+	defer webcam.Close()
+
+	window1 := gocv.NewWindow("Motion Window")
+	defer window1.Close()
+
+	window2 := gocv.NewWindow("Threshold window")
+	defer window2.Close()
+
+	time.Sleep(2 * time.Second)
+
+	img := gocv.NewMat()
+	defer img.Close()
+
+	imgDelta := gocv.NewMat()
+	defer imgDelta.Close()
+
+	imgThresh := gocv.NewMat()
+	defer imgThresh.Close()
+
+	mog2 := gocv.NewBackgroundSubtractorMOG2()
+	defer mog2.Close()
+
+	status := "Ready"
+
+	fmt.Printf("Start reading device: %v\n", deviceID)
+	for {
+		if ok := webcam.Read(&img); !ok {
+			fmt.Printf("Device closed: %v\n", deviceID)
+			return
+		}
+		if img.Empty() {
+			continue
+		}
+
+		status = "READY"
+		statusColor := color.RGBA{0, 255, 0, 0}
+
+		// first phase of cleaning up image, obtain foreground only
+		mog2.Apply(img, &imgDelta)
+
+		// remaining cleanup of the image to use for finding contours.
+		// first use threshold
+		gocv.Threshold(imgDelta, &imgThresh, 25, 255, gocv.ThresholdBinary)
+
+		// then dilate
+		kernel := gocv.GetStructuringElement(gocv.MorphRect, image.Pt(3, 3))
+		defer kernel.Close()
+
+		// Erode
+		gocv.Erode(imgThresh, &imgThresh, kernel)
+		// Dilate
+		gocv.Dilate(imgThresh, &imgThresh, kernel)
+
+		// now find contours
+		contours := gocv.FindContours(imgThresh, gocv.RetrievalExternal, gocv.ChainApproxSimple)
+		for _, c := range contours {
+			area := gocv.ContourArea(c)
+			if area < float64(minArea) {
+				continue
+			}
+
+			status = "MOTION DETECTED"
+			statusColor = color.RGBA{255, 0, 0, 0}
+
+			//gocv.DrawContours(&img, contours, i, statusColor, 2)
+
+			rect := gocv.BoundingRect(c)
+			gocv.Rectangle(&img, rect, color.RGBA{0, 0, 255, 0}, 1)
+		}
+
+		gocv.PutText(&img, status, image.Pt(10, 20), gocv.FontHersheyPlain, 1.2, statusColor, 2)
+
+		window1.IMShow(img)
+		window2.IMShow(imgThresh)
+		if window1.WaitKey(1) == 27 {
+			break
+		}
+	}
+}

go.mod

@@ -12,5 +12,6 @@ require (
 	github.com/mewkiz/flac v1.0.5
 	github.com/pkg/errors v0.8.1
 	github.com/yobert/alsa v0.0.0-20180630182551-d38d89fa843e
+	gocv.io/x/gocv v0.21.0
 	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 )

go.sum

@@ -52,6 +52,8 @@ go.uber.org/multierr v1.1.0/go.mod h1:wR5kodmAFQ0UK8QlbwjlSNy0Z68gJhDJUG5sjR94q/
 go.uber.org/zap v1.9.1/go.mod h1:vwi/ZaCAaUcBkycHslxD9B2zi4UTXhF60s6SWpuDF0Q=
 go.uber.org/zap v1.10.0 h1:ORx85nbTijNz8ljznvCMR1ZBIPKFn3jQrag10X2AsuM=
 go.uber.org/zap v1.10.0/go.mod h1:vwi/ZaCAaUcBkycHslxD9B2zi4UTXhF60s6SWpuDF0Q=
+gocv.io/x/gocv v0.21.0 h1:dVjagrupZrfCRY0qPEaYWgoNMRpBel6GYDH4mvQOK8Y=
+gocv.io/x/gocv v0.21.0/go.mod h1:Rar2PS6DV+T4FL+PM535EImD/h13hGVaHhnCu1xarBs=
 golang.org/x/sys v0.0.0-20190913121621-c3b328c6e5a7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=