commenting and refinement

filter/mog.go

@@ -40,15 +40,15 @@ import (
 // MOGFilter is a filter that provides basic motion detection. MoG is short for
 // Mixture of Gaussians method.
 type MOGFilter struct {
-	dst     io.WriteCloser
-	area    float64
-	bs      *gocv.BackgroundSubtractorMOG2
-	knl     gocv.Mat
-	debug   bool
-	windows []*gocv.Window
-	hold    [][]byte
-	hf      int
-	hfCount int
+	dst     io.WriteCloser                 //writer and closer interface
+	area    float64                        //minimum area that motion
+	bs      *gocv.BackgroundSubtractorMOG2 //Uses the MOG algorithm to find the difference between the current and background frame
+	knl     gocv.Mat                       //matrix that is used for calculations
+	debug   bool                           //if true then debug windows with the bounding boxes and difference will be shown on the screen
+	windows []*gocv.Window                 //holds debug windows
+	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
 }
 
 // NewMOGFilter returns a pointer to a new MOGFilter struct.
@@ -59,8 +59,7 @@ func NewMOGFilter(dst io.WriteCloser, area, threshold float64, history int, debu
 	if debug {
 		windows = []*gocv.Window{gocv.NewWindow("MOG: Bounding boxes"), gocv.NewWindow("MOG: Motion")}
 	}
-	hold := make([][]byte, hf-1)
-	return &MOGFilter{dst, area, &bs, k, debug, windows, hold, hf, 0}
+	return &MOGFilter{dst, area, &bs, k, debug, windows, make([][]byte, hf-1), hf, 0}
 }
 
 // Implements io.Closer.
@@ -82,7 +81,7 @@ func (m *MOGFilter) Write(f []byte) (int, error) {
 	if m.hfCount < (m.hf - 1) {
 		m.hold[m.hfCount] = f
 		m.hfCount++
-		return 0, nil
+		return len(f), nil
 	}
 
 	m.hfCount = 0