diff --git a/service/tool.go b/service/tool.go
index 7230485..c64b932 100644
--- a/service/tool.go
+++ b/service/tool.go
@@ -189,6 +189,9 @@ func getVideoFrame(device proto.DeviceInfo) {
 		if device.NextStop {
 			break
 		}
+		if frame.Empty() {
+			frame = gocv.NewMat()
+		}
 		frame = gocv.NewMat()
 		ok := webcam.Read(&frame)
 		if !ok {