diff --git a/opencv/calib3d/calib3d.go b/opencv/calib3d/calib3d.go
deleted file mode 100644
index ee02884..0000000
--- a/opencv/calib3d/calib3d.go
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2014 <me@cwchang.me>. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Bindings for OpenCV's Calib3d (Camera Calibration
-// and 3D Reconstruction) module
-package calib3d
-
-//#include "../opencv.h"
-//#cgo linux  pkg-config: opencv
-//#cgo darwin pkg-config: opencv
-//#cgo freebsd pkg-config: opencv
-//#cgo windows LDFLAGS: -lopencv_core242.dll -lopencv_imgproc242.dll -lopencv_photo242.dll -lopencv_highgui242.dll -lstdc++
-import "C"
-import "unsafe"
-
-/*
-void cvInitIntrinsicParams2D(
-const CvMat* object_points, const CvMat* image_points,
-const CvMat* npoints, CvSize image_size, CvMat* camera_matrix,
-double aspect_ratio=1. )
-*/
-
-func InitIntrinsicParams2D(objPoints, imgPoints, nPoints *Mat, imgWidth, imgHeight int, aspectRatio float64) (cameraMatrix *Mat) {
-	cameraMatrix = CreateMat(3, 3, CV_64F)
-
-	size := C.cvSize(C.int(imgWidth), C.int(imgHeight))
-
-	C.cvInitIntrinsicParams2D(
-		unsafe.Pointer(objPoints),
-		unsafe.Pointer(imgPoints),
-		unsafe.Pointer(nPoints),
-		size,
-		unsafe.Pointer(cameraMatrix),
-		aspectRatio)
-
-	return cameraMatrix
-}
diff --git a/opencv/calib3d/calib3d_test.go b/opencv/calib3d/calib3d_test.go
deleted file mode 100644
index 34bfa8c..0000000
--- a/opencv/calib3d/calib3d_test.go
+++ /dev/null
@@ -1,9 +0,0 @@
-package calib3d
-
-import (
-	"testing"
-)
-
-func TestInitIntrinsicParams2D(t *testing.T) {
-
-}
diff --git a/opencv/calib3d/go_calib3d.cpp b/opencv/calib3d/go_calib3d.cpp
new file mode 100644
index 0000000..1910eec
--- /dev/null
+++ b/opencv/calib3d/go_calib3d.cpp
@@ -0,0 +1,29 @@
+#include <opencv2/opencv.hpp>
+#include "go_calib3d.hpp"
+#include "iostream"
+#include "vector"
+
+using namespace std;
+
+void
+GoCalib3d::foo() {
+        cout << "Hello there" << endl;
+        vector< vector<cv::Point3f>> objPts;
+        vector< vector<cv::Point2f>> imgPts;
+
+        objPts.push_back(vector<cv::Point3f>());
+        imgPts.push_back(vector<cv::Point2f>());
+
+        objPts[0].push_back(cv::Point3f(0, 25, 0));
+        objPts[0].push_back(cv::Point3f(0, -25, 0));
+        objPts[0].push_back(cv::Point3f(-47, 25, 0));
+        objPts[0].push_back(cv::Point3f(-47, -25, 0));
+
+        imgPts[0].push_back(cv::Point2f(1136.4140625, 1041.89208984));
+        imgPts[0].push_back(cv::Point2f(1845.33190918, 671.39581299));
+        imgPts[0].push_back(cv::Point2f(302.73373413, 634.79998779));
+        imgPts[0].push_back(cv::Point2f(1051.46154785, 352.76107788));
+
+        cv::Mat cameraMatrix = cv::initCameraMatrix2D(objPts, imgPts, cv::Size(1920, 1080), 1);
+        std::cout << cameraMatrix << std::endl;
+}
diff --git a/opencv/calib3d/go_calib3d.go b/opencv/calib3d/go_calib3d.go
new file mode 100644
index 0000000..4aa2eae
--- /dev/null
+++ b/opencv/calib3d/go_calib3d.go
@@ -0,0 +1,5 @@
+package go_calib3d
+
+// #cgo CXXFLAGS: -std=c++11
+// #cgo darwin pkg-config: opencv
+import "C"
diff --git a/opencv/calib3d/go_calib3d.hpp b/opencv/calib3d/go_calib3d.hpp
new file mode 100644
index 0000000..b78be85
--- /dev/null
+++ b/opencv/calib3d/go_calib3d.hpp
@@ -0,0 +1,9 @@
+class GoCalib3d
+{
+public:
+        GoCalib3d () {};
+        virtual ~GoCalib3d () {};
+        void foo();
+private:
+        /* data */
+};
diff --git a/opencv/calib3d/go_calib3d.swigcxx b/opencv/calib3d/go_calib3d.swigcxx
new file mode 100644
index 0000000..98d6160
--- /dev/null
+++ b/opencv/calib3d/go_calib3d.swigcxx
@@ -0,0 +1,7 @@
+%module go_calib3d
+
+%{
+#include "go_calib3d.hpp"
+%}
+
+%include "go_calib3d.hpp"
diff --git a/opencv/calib3d/go_calib3d_test.go b/opencv/calib3d/go_calib3d_test.go
new file mode 100644
index 0000000..ff1546d
--- /dev/null
+++ b/opencv/calib3d/go_calib3d_test.go
@@ -0,0 +1,24 @@
+package go_calib3d
+
+import "testing"
+
+// [[[  0.  25.   0.]
+//   [  0. -25.   0.]
+//   [-47.  25.   0.]
+//   [-47. -25.   0.]]]
+// [[[ 1136.4140625   1041.89208984]
+//   [ 1845.33190918   671.39581299]
+//   [  302.73373413   634.79998779]
+//   [ 1051.46154785   352.76107788]]]
+// (1920, 1080)
+// [[  4.82812906e+03   0.00000000e+00   9.59500000e+02]
+//  [  0.00000000e+00   4.82812906e+03   5.39500000e+02]
+//  [  0.00000000e+00   0.00000000e+00   1.00000000e+00]]
+
+func TestMain(t *testing.T) {
+	// objPoints := opencv.CreateMat(4, 3, opencv.CV_64F)
+	// spew.Dump(objPoints.Get(0, 0))
+	// InitIntrinsicParams2D(objPoints)
+	xxx := NewGoCalib3d()
+	xxx.Foo()
+}