initial commit - untested (hardware pending)

README.md

@@ -1,3 +1,51 @@
 # storage-security
 
-Security solution for my storage locker.  Deployed to a raspberry pi with an attached camera
+Security solution for my storage locker.  Deployed to a raspberry pi with an attached camera.
+
+### Technology Stack
+
+* Raspberry Pi 4 w/ camera
+* GoCV
+* Syncthing
+
+The raspberry pi is configured as a WLAN AP which my phone will connect to.  My phone will also be running syncthing and have the RPI configured as a sync device.  The phone will pull logs and videos taken from the RPI which have been saved to the sync folder each time my phone connects.  
+
+The same folder on my phone is also a syncthing destination with spud, so when I come back upstairs, it uploads it to my server.  
+
+This isn't a foolproof method in case the intruder locates the RPI / camera and disables / destroys it / removes it.  The data is still stored on the RPI until the next time I'm within proximity.  This is an acceptable risk given the constraints, however if a better method is discovered to immediately store the data outside of the storage unit that would be preferred (something low powered sitting in my vehicle? )
+
+### Raspberry Pi Setup
+
+Full steps to re-build this system are below.
+
+##### Prerequisites 
+
+1. Connect the camera
+2. Image the SDcard with Raspberry Pi OS Lite (minimal image based on debian) - make sure to pick lite - do not use the desktop version. 
+
+##### Boot optimizations
+
+Edit /boot/config.txt
+
+```conf
+# Disable the rainbow splash screen
+disable_splash=1
+
+# Disable bluetooth
+dtoverlay=pi3-disable-bt
+ 
+# Set the bootloader delay to 0 seconds. The default is 1s if not specified.
+boot_delay=0
+```
+
+Edit /boot/cmdline.txt to make kernel quiet.  The following is an example, the key part is the quiet flag
+
+```conf
+dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=32e07f87-02 rootfstype=ext4 elevator=deadline fsck.repair=yes quiet rootwait
+```
+
+Disable dhcpcd - useless service in this case
+
+```bash
+sudo systemctl disable dhcpcd.service
+```

main.go

@@ -0,0 +1,127 @@
+package main
+
+import (
+	"fmt"
+	"image"
+	"image/color"
+	"log"
+	"os"
+	"time"
+
+	"gocv.io/x/gocv"
+)
+
+const (
+	minimumMotionArea       = 3000 // Motion detection minimum area needed to move
+	recordLengthAfterMotion = 30   // Number of seconds to keep recording going after motion was last detected
+	motionDetectInterval    = 1    //number of seconds between motion detection attempts // TBD: Implement this, currently does nothing
+)
+
+var (
+	lastMotionDetectedTime   time.Time
+	currentRecording         *gocv.VideoWriter
+	img, imgDelta, imgThresh gocv.Mat
+	mog2                     gocv.BackgroundSubtractorMOG2
+	osdColor                 color.RGBA
+)
+
+func init() {
+	if len(os.Args) < 2 {
+		fmt.Println("How to run:\n\tstorage-security [camera ID]")
+		return
+	}
+
+	img = gocv.NewMat()
+	imgDelta = gocv.NewMat()
+	imgThresh = gocv.NewMat()
+	mog2 = gocv.NewBackgroundSubtractorMOG2()
+	osdColor = color.RGBA{0, 0, 255, 0}
+}
+
+func main() {
+	defer img.Close()
+	defer imgDelta.Close()
+	defer imgThresh.Close()
+	defer mog2.Close()
+
+	// parse args
+	deviceID := os.Args[1]
+
+	webcam, err := gocv.OpenVideoCapture(deviceID)
+	if err != nil {
+		fmt.Printf("Error opening video capture device: %v\n", deviceID)
+		return
+	}
+	defer webcam.Close()
+
+	fmt.Printf("Start reading device: %v\n", deviceID)
+
+	// main loop
+	for {
+		if ok := webcam.Read(&img); !ok {
+			fmt.Printf("Device closed: %v\n", deviceID)
+			return
+		}
+		if img.Empty() {
+			continue
+		}
+
+		if detectMotion(img) {
+			// Determine if a new recording needs to start
+			if time.Now().After(lastMotionDetectedTime.Add(time.Second * recordLengthAfterMotion)) {
+				fileName := fmt.Sprintf("storage-%s.avi", time.Now().Format(time.RFC3339))
+				log.Printf("motion detected, started recording to file named %s", fileName)
+				currentRecording, err = gocv.VideoWriterFile(fileName, "MJPG", 25, img.Cols(), img.Rows(), true)
+				if err != nil {
+					fmt.Printf("error opening video writer device: %v\n", err)
+					return
+				}
+			}
+			// And always update the timestamp
+			lastMotionDetectedTime = time.Now()
+		}
+
+		// Determine if we are currently recording and if so, then save the frame to the video
+		if currentRecording != nil {
+			// OSD / timestamp
+			gocv.PutText(&img, time.Now().Format(time.RFC3339), image.Pt(10, 20), gocv.FontHersheyPlain, 1.2, osdColor, 2)
+
+			currentRecording.Write(img)
+			// Determine if we should stop recording
+			if lastMotionDetectedTime.Add(time.Second * recordLengthAfterMotion).After(time.Now()) {
+				log.Printf("motion has not been detected for the last %d seconds stopping recording to file", recordLengthAfterMotion)
+				err = currentRecording.Close()
+				if err != nil {
+					log.Printf("failed to close openCV file recording handle: %v", err)
+				}
+				currentRecording = nil
+			}
+		}
+	}
+}
+
+// Returns true if motion detected in current frame
+func detectMotion(frame gocv.Mat) bool {
+	// first phase of cleaning up image, obtain foreground only
+	mog2.Apply(frame, &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()
+	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 < minimumMotionArea {
+			continue
+		}
+		return true
+	}
+	return false
+}