Merged in motion-pixel-interval (pull request #367)

filter: Motion detection filter pixel interval

Approved-by: Saxon Milton <saxon.milton@gmail.com>

filter/filters_circleci.go

@@ -32,12 +32,12 @@ import (
 )
 
 // NewMOG returns a pointer to a new NoOp struct for testing purposes only.
-func NewMOG(dst io.WriteCloser, area, threshold float64, history int, debug bool, hf int) *NoOp {
+func NewMOG(dst io.WriteCloser, area, threshold float64, history int, debug bool, hf int, scaleFactor int) *NoOp {
 	return &NoOp{dst: dst}
 }
 
 // NewKNN returns a pointer to a new NoOp struct for testing purposes only.
-func NewKNN(dst io.WriteCloser, area, threshold float64, history, kernelSize int, debug bool, hf int) *NoOp {
+func NewKNN(dst io.WriteCloser, area, threshold float64, history, kernelSize int, debug bool, hf int, scaleFactor int) *NoOp {
 	return &NoOp{dst: dst}
 }
 

filter/knn.go

@@ -49,17 +49,18 @@ type KNN struct {
 	hold    [][]byte                      // Will hold all frames up to hf (so only every hf frame is motion detected).
 	hf      int                           // The number of frames to be held.
 	hfCount int                           // Counter for the hold array.
+	scale   float64                       // The factor that frames will be downscaled by for motion detection.
 }
 
 // NewKNN returns a pointer to a new KNN filter struct.
-func NewKNN(dst io.WriteCloser, area, threshold float64, history, kernelSize int, debug bool, hf int) *KNN {
+func NewKNN(dst io.WriteCloser, area, threshold float64, history, kernelSize int, debug bool, hf int, scaleFactor int) *KNN {
 	bs := gocv.NewBackgroundSubtractorKNNWithParams(history, threshold, false)
 	k := gocv.GetStructuringElement(gocv.MorphRect, image.Pt(kernelSize, kernelSize))
 	var windows []*gocv.Window
 	if debug {
 		windows = []*gocv.Window{gocv.NewWindow("KNN: Bounding boxes"), gocv.NewWindow("KNN: Motion")}
 	}
-	return &KNN{dst, area, &bs, k, debug, windows, make([][]byte, hf-1), hf, 0}
+	return &KNN{dst, area, &bs, k, debug, windows, make([][]byte, hf-1), hf, 0, 1 / float64(scaleFactor)}
 }
 
 // Implements io.Closer.
@@ -94,6 +95,9 @@ func (m *KNN) Write(f []byte) (int, error) {
 	imgDelta := gocv.NewMat()
 	defer imgDelta.Close()
 
+	// Downsize image to speed up calculations.
+	gocv.Resize(img, &img, image.Point{}, m.scale, m.scale, gocv.InterpolationNearestNeighbor)
+
 	// Seperate foreground and background.
 	m.bs.Apply(img, &imgDelta)
 

filter/mog.go

@@ -49,17 +49,18 @@ type MOG struct {
 	hold    [][]byte                       // Will hold all frames up to hf (so only every hf frame is motion detected).
 	hf      int                            // The number of frames to be held.
 	hfCount int                            // Counter for the hold array.
+	scale   float64                        // The factor that frames will be downscaled by for motion detection.
 }
 
 // NewMOG returns a pointer to a new MOG filter struct.
-func NewMOG(dst io.WriteCloser, area, threshold float64, history int, debug bool, hf int) *MOG {
+func NewMOG(dst io.WriteCloser, area, threshold float64, history int, debug bool, hf int, scaleFactor int) *MOG {
 	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 &MOG{dst, area, &bs, k, debug, windows, make([][]byte, hf-1), hf, 0}
+	return &MOG{dst, area, &bs, k, debug, windows, make([][]byte, hf-1), hf, 0, 1 / float64(scaleFactor)}
 }
 
 // Implements io.Closer.
@@ -94,6 +95,9 @@ func (m *MOG) Write(f []byte) (int, error) {
 	imgDelta := gocv.NewMat()
 	defer imgDelta.Close()
 
+	// Downsize image to speed up calculations.
+	gocv.Resize(img, &img, image.Point{}, m.scale, m.scale, gocv.InterpolationNearestNeighbor)
+
 	// Seperate foreground and background.
 	m.bs.Apply(img, &imgDelta)
 

revid/config/config.go

@@ -85,7 +85,6 @@ const (
 	defaultClipDuration    = 0
 	defaultAudioInputCodec = codecutil.ADPCM
 	defaultPSITime         = 2
-	defaultMotionInterval  = 5
 	defaultFileFPS         = 0
 
 	// Ring buffer defaults.
@@ -95,6 +94,8 @@ const (
 
 	// Motion filter parameter defaults.
 	defaultMinFPS            = 1.0
+	defaultMotionDownscaling = 1
+	defaultMotionInterval    = 1
 
 	// KNN filter parameter defaults.
 	defaultKNNMinArea   = 25.0
@@ -283,7 +284,6 @@ 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.
-	MotionInterval 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.
@@ -293,6 +293,8 @@ type Config struct {
 
 	// Motion filter parameters.
 	MinFPS            float64 // The reduced framerate of the video when there is no motion.
+	MotionInterval    int     // Sets the number of frames that are held before the filter is used (on the nth frame)
+	MotionDownscaling int     // Downscaling factor of frames used for motion detection.
 
 	// KNN filter parameters.
 	KNNMinArea   float64 // Used to ignore small areas of motion detection.
@@ -303,8 +305,12 @@ type Config struct {
 	// MOG filter parameters.
 	MOGMinArea   float64 // Used to ignore small areas of motion detection.
 	MOGThreshold float64 // Intensity value from the KNN motion detection algorithm that is considered motion.
-	MOGHistory   uint    // Length of MOG filter's history
+	MOGHistory   uint    // Length of MOG filter's history.
 
+	// Difference filter parameters.
+	DiffThreshold float64 // Intensity value from the Difference motion detection algorithm that is considered motion.
+
+	// Basic filter parameters.
 	BasicThreshold int
 	BasicPixels    int
 
@@ -313,8 +319,6 @@ type Config struct {
 
 	// Defines the rate at which frames from a file source are processed.
 	FileFPS int
-	// Difference filter parameters.
-	DiffThreshold float64 // Intensity value from the Difference motion detection algorithm that is considered motion.
 }
 
 // TypeData contains information about all of the variables that
@@ -353,6 +357,7 @@ var TypeData = map[string]string{
 	"MOGHistory":        "uint",
 	"MOGMinArea":        "float",
 	"MOGThreshold":      "float",
+	"MotionDownscaling": "uint",
 	"MotionInterval":    "int",
 	"Output":            "enum:File,Http,Rtmp,Rtp",
 	"OutputPath":        "string",
@@ -544,6 +549,11 @@ func (c *Config) Validate() error {
 		c.BasicPixels = defaultBasicPixels
 	}
 
+	if c.MotionDownscaling <= 0 {
+		c.logInvalidField("MotionDownscaling", defaultMotionDownscaling)
+		c.MotionDownscaling = defaultMotionDownscaling
+	}
+
 	if c.ShowWindows {
 		os, err := osName()
 		if err != nil {

revid/revid.go

@@ -341,11 +341,11 @@ 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.NewMOG(dst, r.cfg.MOGMinArea, r.cfg.MOGThreshold, int(r.cfg.MOGHistory), r.cfg.ShowWindows, r.cfg.MotionInterval)
+				r.filters[i] = filter.NewMOG(dst, r.cfg.MOGMinArea, r.cfg.MOGThreshold, int(r.cfg.MOGHistory), r.cfg.ShowWindows, r.cfg.MotionInterval, r.cfg.MotionDownscaling)
 			case config.FilterVariableFPS:
-				r.filters[i] = filter.NewVariableFPS(dst, r.cfg.MinFPS, filter.NewMOG(dst, r.cfg.MOGMinArea, r.cfg.MOGThreshold, int(r.cfg.MOGHistory), r.cfg.ShowWindows, r.cfg.MotionInterval))
+				r.filters[i] = filter.NewVariableFPS(dst, r.cfg.MinFPS, filter.NewMOG(dst, r.cfg.MOGMinArea, r.cfg.MOGThreshold, int(r.cfg.MOGHistory), r.cfg.ShowWindows, r.cfg.MotionInterval, r.cfg.MotionDownscaling))
 			case config.FilterKNN:
-				r.filters[i] = filter.NewKNN(dst, r.cfg.KNNMinArea, r.cfg.KNNThreshold, int(r.cfg.KNNHistory), int(r.cfg.KNNKernel), r.cfg.ShowWindows, r.cfg.MotionInterval)
+				r.filters[i] = filter.NewKNN(dst, r.cfg.KNNMinArea, r.cfg.KNNThreshold, int(r.cfg.KNNHistory), int(r.cfg.KNNKernel), r.cfg.ShowWindows, r.cfg.MotionInterval, r.cfg.MotionDownscaling)
 			case config.FilterDifference:
 				r.filters[i] = filter.NewDifference(dst, r.cfg.ShowWindows, r.cfg.DiffThreshold)
 			case config.FilterBasic:
@@ -904,6 +904,13 @@ func (r *Revid) Update(vars map[string]string) error {
 			if value == "Loop" {
 				r.cfg.Loop = true
 			}
+		case "MotionDownscaling":
+			v, err := strconv.Atoi(value)
+			if err != nil {
+				r.cfg.Logger.Log(logger.Warning, pkg+"invalid MotionDownscaling var", "value", value)
+				break
+			}
+			r.cfg.MotionDownscaling = v
 		}
 	}
 	r.cfg.Logger.Log(logger.Info, pkg+"revid config changed", "config", fmt.Sprintf("%+v", r.cfg))