implement frameskip for motion detection

reduce power consumption

main.go

@@ -14,7 +14,7 @@ import (
 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
+	motionDetectInterval    = 30   //number of frames between motion detection attempts // TBD: Implement this, currently does nothing
 )
 
 var (
@@ -65,6 +65,8 @@ func main() {
 		detectMotion(img)
 	}
 
+	frameCount := 0
+
 	// main loop
 	for {
 		if ok := webcam.Read(&img); !ok {
@@ -75,6 +77,7 @@ func main() {
 			continue
 		}
 
+		if frameCount >= motionDetectInterval {
 			if detectMotion(img) {
 				// Determine if a new recording needs to start
 				if time.Now().After(lastMotionDetectedTime.Add(time.Second * recordLengthAfterMotion)) {
@@ -89,6 +92,8 @@ func main() {
 				// And always update the timestamp
 				lastMotionDetectedTime = time.Now()
 			}
+			frameCount = 0
+		}
 
 		// Determine if we are currently recording and if so, then save the frame to the video
 		if currentRecording != nil {