From 4b285589243ffe208fb9845b10cf50272ac4c4b2 Mon Sep 17 00:00:00 2001
From: Scott <scott@ausocean.org>
Date: Wed, 8 Jan 2020 11:31:09 +1030
Subject: [PATCH] Frame counter resets on a consistent interval.

---
 filter/mog.go | 131 +++++++++++++++++++++++++-------------------------
 1 file changed, 66 insertions(+), 65 deletions(-)

diff --git a/filter/mog.go b/filter/mog.go
index bd916791..243044e7 100644
--- a/filter/mog.go
+++ b/filter/mog.go
@@ -84,70 +84,71 @@ func (m *MOGFilter) Write(f []byte) (int, error) {
 		m.hold[hfCount] = f
 		hfCount++
 		return 0, nil
-	} else {
-		img, err := gocv.IMDecode(f, gocv.IMReadColor)
-		if err != nil {
-			return 0, fmt.Errorf("image can't be decoded: %w", err)
-		}
-		defer img.Close()
-
-		imgDelta := gocv.NewMat()
-		defer imgDelta.Close()
-
-		// Seperate foreground and background.
-		m.bs.Apply(img, &imgDelta)
-
-		// Threshold imgDelta.
-		gocv.Threshold(imgDelta, &imgDelta, 25, 255, gocv.ThresholdBinary)
-
-		// Remove noise.
-		gocv.Erode(imgDelta, &imgDelta, m.knl)
-		gocv.Dilate(imgDelta, &imgDelta, m.knl)
-
-		// Fill small holes.
-		gocv.Dilate(imgDelta, &imgDelta, m.knl)
-		gocv.Erode(imgDelta, &imgDelta, m.knl)
-
-		// Find contours and reject ones with a small area.
-		var contours [][]image.Point
-		allContours := gocv.FindContours(imgDelta, gocv.RetrievalExternal, gocv.ChainApproxSimple)
-		for _, c := range allContours {
-			if gocv.ContourArea(c) > m.area {
-				contours = append(contours, c)
-			}
-		}
-
-		// Draw debug information.
-		if m.debug {
-			for _, c := range contours {
-				rect := gocv.BoundingRect(c)
-				gocv.Rectangle(&img, rect, color.RGBA{0, 0, 255, 0}, 1)
-			}
-
-			if len(contours) > 0 {
-				gocv.PutText(&img, "Motion", image.Pt(32, 32), gocv.FontHersheyPlain, 2.0, color.RGBA{255, 0, 0, 0}, 2)
-			}
-
-			m.windows[0].IMShow(img)
-			m.windows[1].IMShow(imgDelta)
-			m.windows[0].WaitKey(1)
-		}
-
-		// Don't write to destination if there is no motion.
-		if len(contours) == 0 {
-			return 0, nil
-		}
-
-		// Write to destination, past 4 frames then current frame.
-		for i, h := range m.hold {
-			_, err := m.dst.Write(h)
-			m.hold[i] = nil
-			if err != nil {
-				return 0, err
-			}
-		}
-
-		hfCount = 0
-		return m.dst.Write(f)
 	}
+
+	hfCount = 0
+	img, err := gocv.IMDecode(f, gocv.IMReadColor)
+	if err != nil {
+		return 0, fmt.Errorf("image can't be decoded: %w", err)
+	}
+	defer img.Close()
+
+	imgDelta := gocv.NewMat()
+	defer imgDelta.Close()
+
+	// Seperate foreground and background.
+	m.bs.Apply(img, &imgDelta)
+
+	// Threshold imgDelta.
+	gocv.Threshold(imgDelta, &imgDelta, 25, 255, gocv.ThresholdBinary)
+
+	// Remove noise.
+	gocv.Erode(imgDelta, &imgDelta, m.knl)
+	gocv.Dilate(imgDelta, &imgDelta, m.knl)
+
+	// Fill small holes.
+	gocv.Dilate(imgDelta, &imgDelta, m.knl)
+	gocv.Erode(imgDelta, &imgDelta, m.knl)
+
+	// Find contours and reject ones with a small area.
+	var contours [][]image.Point
+	allContours := gocv.FindContours(imgDelta, gocv.RetrievalExternal, gocv.ChainApproxSimple)
+	for _, c := range allContours {
+		if gocv.ContourArea(c) > m.area {
+			contours = append(contours, c)
+		}
+	}
+
+	// Draw debug information.
+	if m.debug {
+		for _, c := range contours {
+			rect := gocv.BoundingRect(c)
+			gocv.Rectangle(&img, rect, color.RGBA{0, 0, 255, 0}, 1)
+		}
+
+		if len(contours) > 0 {
+			gocv.PutText(&img, "Motion", image.Pt(32, 32), gocv.FontHersheyPlain, 2.0, color.RGBA{255, 0, 0, 0}, 2)
+		}
+
+		m.windows[0].IMShow(img)
+		m.windows[1].IMShow(imgDelta)
+		m.windows[0].WaitKey(1)
+	}
+
+	// Don't write to destination if there is no motion.
+	if len(contours) == 0 {
+		return 0, nil
+	}
+
+	// Write to destination, past 4 frames then current frame.
+	for i, h := range m.hold {
+		_, err := m.dst.Write(h)
+		m.hold[i] = nil
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	return m.dst.Write(f)
+
 }