diff --git a/filter/basic.go b/filter/basic.go
index f2d7f3d2..138d106a 100644
--- a/filter/basic.go
+++ b/filter/basic.go
@@ -142,7 +142,7 @@ func (bf *Basic) Write(f []byte) (int, error) {
 	}
 
 	// If there are not enough motion pixels then discard the frame.
-	if bf.motion < pixels {
+	if bf.motion < bf.pix {
 		return len(f), nil
 	}
 
@@ -163,12 +163,12 @@ func (bf *Basic) process(j int, wg *sync.WaitGroup) {
 
 		diff := diffR + diffG + diffB
 
-		if diff > threshold {
+		if diff > bf.thresh {
 			bf.motion++
 		}
 
 		if bf.debug {
-			if diff > threshold {
+			if diff > bf.thresh {
 				bf.bwImg.SetRGBA(i, j, color.RGBA{0xff, 0xff, 0xff, 0xff})
 			} else {
 				bf.bwImg.SetRGBA(i, j, color.RGBA{0x00, 0x00, 0x00, 0xff})