added missing Empty method

contrib/face.cpp

@@ -1,5 +1,9 @@
 #include "face.h"
 
+bool FaceRecognizer_Empty(FaceRecognizer fr) {
+    return (*fr)->empty();
+}
+
 void FaceRecognizer_Train(FaceRecognizer fr, Mats mats, IntVector labels_in) {
     std::vector<int> labels;
 

contrib/face.go

@@ -25,6 +25,10 @@ type LBPHFaceRecognizer struct {
 	p C.LBPHFaceRecognizer
 }
 
+func (fr *LBPHFaceRecognizer) Empty() bool {
+	return faceRecognizer_Empty(C.FaceRecognizer(fr.p))
+}
+
 // NewLBPHFaceRecognizer creates a new LBPH Recognizer model.
 //
 // For further information, see:

contrib/face.h

@@ -23,6 +23,7 @@ struct PredictResponse {
     double confidence;
 };
 
+bool FaceRecognizer_Empty(FaceRecognizer fr);
 void FaceRecognizer_Train(FaceRecognizer fr, Mats images, IntVector labels);
 void FaceRecognizer_Update(FaceRecognizer fr, Mats images, IntVector labels);
 int FaceRecognizer_Predict(FaceRecognizer fr, Mat sample);
@@ -44,6 +45,9 @@ int LBPHFaceRecognizer_GetGridX(LBPHFaceRecognizer fr);
 int LBPHFaceRecognizer_GetGridY(LBPHFaceRecognizer fr);
 void LBPHFaceRecognizer_Close(LBPHFaceRecognizer fr);
 
+
+
+
 #ifdef __cplusplus
 }
 #endif

contrib/face_recognizer.go

@@ -12,6 +12,7 @@ import (
 )
 
 type FaceRecognizer interface {
+	Empty() bool
 	Train(images []gocv.Mat, labels []int)
 	Update(newImages []gocv.Mat, newLabels []int)
 	Predict(sample gocv.Mat) int
@@ -23,6 +24,11 @@ type FaceRecognizer interface {
 	Close() error
 }
 
+func faceRecognizer_Empty(fr C.FaceRecognizer) bool {
+	b := C.FaceRecognizer_Empty(fr)
+	return bool(b)
+}
+
 func faceRecognizer_Train(fr C.FaceRecognizer, images []gocv.Mat, labels []int) {
 	cparams := []C.int{}
 	for _, v := range labels {

contrib/face_test.go

@@ -14,6 +14,8 @@ func TestLBPHFaceRecognizer_Methods(t *testing.T) {
 		t.Errorf("Invalid NewLBPHFaceRecognizer call %v", model)
 	}
 
+	model.Empty()
+
 	labels := []int{1, 1, 1, 1, 2, 2, 2, 2}
 	images := []gocv.Mat{
 		gocv.IMRead("./att_faces/s1/1.pgm", gocv.IMReadGrayScale),