making mog filter that only dectects motion on every 5 frame (will make this a var)

filter/mog.go

@@ -46,17 +46,22 @@ type MOGFilter struct {
 	knl     gocv.Mat
 	debug   bool
 	windows []*gocv.Window
+	hold    [][]byte
+	hf      int
 }
 
+var hfCount int = 0
+
 // NewMOGFilter returns a pointer to a new MOGFilter struct.
-func NewMOGFilter(dst io.WriteCloser, area, threshold float64, history int, debug bool) *MOGFilter {
+func NewMOGFilter(dst io.WriteCloser, area, threshold float64, history int, debug bool, hf int) *MOGFilter {
 	bs := gocv.NewBackgroundSubtractorMOG2WithParams(history, threshold, false)
 	k := gocv.GetStructuringElement(gocv.MorphRect, image.Pt(3, 3))
 	var windows []*gocv.Window
 	if debug {
 		windows = []*gocv.Window{gocv.NewWindow("MOG: Bounding boxes"), gocv.NewWindow("MOG: Motion")}
 	}
-	return &MOGFilter{dst, area, &bs, k, debug, windows}
+	hold := make([][]byte, hf-1)
+	return &MOGFilter{dst, area, &bs, k, debug, windows, hold, hf}
 }
 
 // Implements io.Closer.
@@ -75,6 +80,11 @@ func (m *MOGFilter) Close() error {
 // Write applies the motion filter to the video stream. Only frames with motion
 // are written to the destination encoder, frames without are discarded.
 func (m *MOGFilter) Write(f []byte) (int, error) {
+	if hfCount < (m.hf - 1) {
+		m.hold[hfCount] = f
+		hfCount++
+		return -1, nil
+	} else {
 		img, err := gocv.IMDecode(f, gocv.IMReadColor)
 		if err != nil {
 			return 0, fmt.Errorf("image can't be decoded: %w", err)
@@ -128,6 +138,16 @@ func (m *MOGFilter) Write(f []byte) (int, error) {
 			return 0, nil
 		}
 
-	// Write to destination.
+		// Write to destination, past 4 frames then current frame.
+		for _, h := range m.hold {
+			_, err := m.dst.Write(h)
+			if err != nil {
+				return 0, err
+			}
+		}
+
+		hfCount = 0
 		return m.dst.Write(f)
 	}
+
+}

revid/config/config.go

@@ -85,6 +85,7 @@ const (
 	defaultClipDuration    = 0
 	defaultAudioInputCodec = codecutil.ADPCM
 	defaultPSITime         = 2
+	defaultFilterFrames    = 1
 
 	// Ring buffer defaults.
 	defaultRBMaxElements  = 10000
@@ -275,6 +276,7 @@ type Config struct {
 	HorizontalFlip bool  // HorizontalFlip flips video horizontally for Raspivid input.
 	VerticalFlip   bool  // VerticalFlip flips video vertically for Raspivid input.
 	Filters        []int // Defines the methods of filtering to be used in between lexing and encoding.
+	FilterFrames   int   // Sets the number of frames that are held before the filter is used (on the nth frame)
 	PSITime        int   // Sets the time between a packet being sent.
 
 	// Ring buffer parameters.
@@ -460,6 +462,10 @@ func (c *Config) Validate() error {
 		c.Logger.Log(logger.Info, pkg+"PSITime bad or unset, defaulting", "PSITime", defaultPSITime)
 		c.PSITime = defaultPSITime
 	}
+	if c.FilterFrames <= 0 {
+		c.Logger.Log(logger.Info, pkg+"FilterFrames bad or unset, defaulting", "FilterFrames", defaultFilterFrames)
+		c.FilterFrames = defaultFilterFrames
+	}
 
 	if c.MinFPS <= 0 {
 		c.Logger.Log(logger.Info, pkg+"MinFPS bad or unset, defaulting", "MinFPS", defaultMinFPS)

revid/revid.go

@@ -63,6 +63,24 @@ const (
 	rtmpConnectionTimeout  = 10
 )
 
+// Motion filter parameters.
+const minFPS = 1.0
+
+// KNN specific parameters.
+const (
+	knnMinArea   = 25.0
+	knnThreshold = 300
+	knnHistory   = 300
+	knnKernel    = 9
+)
+
+// MOG specific parameters.
+const (
+	mogMinArea   = 50
+	mogThreshold = 100
+	mogHistory   = 100
+)
+
 const pkg = "revid: "
 
 type Logger interface {
@@ -337,17 +355,16 @@ func (r *Revid) setupPipeline(mtsEnc func(dst io.WriteCloser, rate float64) (io.
 			case config.FilterNoOp:
 				r.filters[i] = filter.NewNoOp(dst)
 			case config.FilterMOG:
-				r.filters[i] = filter.NewMOGFilter(dst, r.cfg.MOGMinArea, r.cfg.MOGThreshold, int(r.cfg.MOGHistory), r.cfg.ShowWindows)
+				r.filters[i] = filter.NewMOGFilter(dst, mogMinArea, mogThreshold, mogHistory, r.cfg.ShowWindows, r.cfg.FilterFrames)
 			case config.FilterVariableFPS:
-				r.filters[i] = filter.NewVariableFPSFilter(dst, r.cfg.MinFPS, filter.NewMOGFilter(dst, r.cfg.MOGMinArea, r.cfg.MOGThreshold, int(r.cfg.MOGHistory), r.cfg.ShowWindows))
+				r.filters[i] = filter.NewVariableFPSFilter(dst, minFPS, filter.NewMOGFilter(r.encoders, mogMinArea, mogThreshold, mogHistory, r.cfg.ShowWindows, r.cfg.FilterFrames))
 			case config.FilterKNN:
-				r.filters[i] = filter.NewKNNFilter(dst, r.cfg.KNNMinArea, r.cfg.KNNThreshold, int(r.cfg.KNNHistory), int(r.cfg.KNNKernel), r.cfg.ShowWindows)
+				r.filters[i] = filter.NewKNNFilter(dst, knnMinArea, knnThreshold, knnHistory, knnKernel, r.cfg.ShowWindows)
 			default:
 				panic("Undefined Filter")
 			}
 			dst = r.filters[i]
 		}
-
 	}
 
 	switch r.cfg.Input {
@@ -671,6 +688,13 @@ func (r *Revid) Update(vars map[string]string) error {
 				}
 				r.cfg.Filters[i] = v
 			}
+		case "FilterFrames":
+			v, err := strconv.Atoi(value)
+			if err != nil || v < 0 {
+				r.cfg.Logger.Log(logger.Warning, pkg+"invalid FilterFrames var", "value", value)
+				break
+			}
+			r.cfg.FilterFrames = v
 		case "PSITime":
 			v, err := strconv.Atoi(value)
 			if err != nil || v < 0 {