diff --git a/include/mynteye/types.h b/include/mynteye/types.h
index ddb63b7..a6fd97c 100644
--- a/include/mynteye/types.h
+++ b/include/mynteye/types.h
@@ -417,16 +417,21 @@ inline std::ostream &operator<<(std::ostream &os,
 
 struct MYNTEYE_API IntrinsicsBase {
   IntrinsicsBase() {
-    calib_model = CalibrationModel::UNKNOW;
+    calib_model_ = CalibrationModel::UNKNOW;
   }
   virtual ~IntrinsicsBase() {}
 
   /** The calibration model */
-  CalibrationModel calib_model;
+  CalibrationModel calib_model() const {
+    return calib_model_;
+  }
   /** The width of the image in pixels */
   std::uint16_t width;
   /** The height of the image in pixels */
   std::uint16_t height;
+
+ protected:
+  CalibrationModel calib_model_;
 };
 
 /**
@@ -435,7 +440,7 @@ struct MYNTEYE_API IntrinsicsBase {
  */
 struct MYNTEYE_API IntrinsicsPinhole : public IntrinsicsBase {
   IntrinsicsPinhole() {
-    calib_model = CalibrationModel::PINHOLE;
+    calib_model_ = CalibrationModel::PINHOLE;
   }
   /** The focal length of the image plane, as a multiple of pixel width */
   double fx;
@@ -465,7 +470,7 @@ using Intrinsics = IntrinsicsPinhole;
  */
 struct MYNTEYE_API IntrinsicsEquidistant : public IntrinsicsBase {
   IntrinsicsEquidistant() {
-    calib_model = CalibrationModel::KANNALA_BRANDT;
+    calib_model_ = CalibrationModel::KANNALA_BRANDT;
   }
   /** The distortion coefficients: k2,k3,k4,k5,mu,mv,u0,v0 */
   double coeffs[8];
diff --git a/src/mynteye/api/api.cc b/src/mynteye/api/api.cc
index e6986f6..1299bdb 100644
--- a/src/mynteye/api/api.cc
+++ b/src/mynteye/api/api.cc
@@ -296,7 +296,7 @@ std::string API::GetInfo(const Info &info) const {
 
 IntrinsicsPinhole API::GetIntrinsics(const Stream &stream) const {
   auto in = GetIntrinsicsBase(stream);
-  if (in->calib_model == CalibrationModel::PINHOLE) {
+  if (in->calib_model() == CalibrationModel::PINHOLE) {
     return *std::dynamic_pointer_cast<IntrinsicsPinhole>(in);
   }
   throw std::runtime_error("Intrinsics is not pinhole model"
diff --git a/src/mynteye/api/processor/rectify_processor.cc b/src/mynteye/api/processor/rectify_processor.cc
index 334575a..09d1e4e 100644
--- a/src/mynteye/api/processor/rectify_processor.cc
+++ b/src/mynteye/api/processor/rectify_processor.cc
@@ -43,12 +43,12 @@ std::string RectifyProcessor::Name() {
 void RectifyProcessor::NotifyImageParamsChanged() {
   auto in_left = device_->GetIntrinsics(Stream::LEFT);
   auto in_right = device_->GetIntrinsics(Stream::RIGHT);
-  if (in_left->calib_model == CalibrationModel::PINHOLE) {
+  if (in_left->calib_model() == CalibrationModel::PINHOLE) {
     InitParams(
       *std::dynamic_pointer_cast<IntrinsicsPinhole>(in_left),
       *std::dynamic_pointer_cast<IntrinsicsPinhole>(in_right),
       device_->GetExtrinsics(Stream::RIGHT, Stream::LEFT));
-  } else if (in_left->calib_model ==
+  } else if (in_left->calib_model() ==
              CalibrationModel::KANNALA_BRANDT) {
     InitParams(
       *std::dynamic_pointer_cast<IntrinsicsEquidistant>(in_left),
diff --git a/src/mynteye/device/channel/bytes.cc b/src/mynteye/device/channel/bytes.cc
index b84c66f..b0624f9 100644
--- a/src/mynteye/device/channel/bytes.cc
+++ b/src/mynteye/device/channel/bytes.cc
@@ -32,7 +32,7 @@ std::string _from_data(const std::uint8_t *data, std::size_t count) {
 
 std::size_t from_data(IntrinsicsBase *in, const std::uint8_t *data,
     bool get_size) {
-  switch (in->calib_model) {
+  switch (in->calib_model()) {
     case CalibrationModel::PINHOLE:
       return from_data(dynamic_cast<IntrinsicsPinhole *>(in), data,
           get_size);
@@ -40,7 +40,7 @@ std::size_t from_data(IntrinsicsBase *in, const std::uint8_t *data,
       return from_data(dynamic_cast<IntrinsicsEquidistant *>(in), data,
           get_size);
     default:
-      LOG(FATAL) << "Unknown calib model: " << in->calib_model;
+      LOG(FATAL) << "Unknown calib model: " << in->calib_model();
   }
 }
 
@@ -163,7 +163,7 @@ std::size_t _to_data(std::string value, std::uint8_t *data, std::size_t count) {
 
 std::size_t to_data(const IntrinsicsBase *in, std::uint8_t *data,
     bool set_size) {
-  switch (in->calib_model) {
+  switch (in->calib_model()) {
     case CalibrationModel::PINHOLE:
       return to_data(dynamic_cast<const IntrinsicsPinhole *>(in), data,
           set_size);
@@ -171,7 +171,7 @@ std::size_t to_data(const IntrinsicsBase *in, std::uint8_t *data,
       return to_data(dynamic_cast<const IntrinsicsEquidistant *>(in), data,
           set_size);
     default:
-      LOG(FATAL) << "Unknown calib model: " << in->calib_model;
+      LOG(FATAL) << "Unknown calib model: " << in->calib_model();
   }
 }
 
diff --git a/src/mynteye/device/channel/file_channel.cc b/src/mynteye/device/channel/file_channel.cc
index f24df2c..e7342d0 100644
--- a/src/mynteye/device/channel/file_channel.cc
+++ b/src/mynteye/device/channel/file_channel.cc
@@ -334,10 +334,8 @@ std::size_t ImgParamsParser::GetFromData_new(
       i += bytes::from_data(in_left.get(), data + i, false);
       i += bytes::from_data(in_right.get(), data + i, false);
       i += bytes::from_data(&ex_right_to_left, data + i);
-      in_left->calib_model = calib_model;
       in_left->width = width;
       in_left->height = height;
-      in_right->calib_model = calib_model;
       in_right->width = width;
       in_right->height = height;
       (*img_params)[{width, height}] = {true, version.to_string(),
@@ -369,7 +367,7 @@ std::size_t ImgParamsParser::SetToData_new(
     for (auto &&entry : *img_params) {
       auto &&params = entry.second;
       // calib_model, 1
-      data[i] = static_cast<std::uint8_t>(params.in_left->calib_model);
+      data[i] = static_cast<std::uint8_t>(params.in_left->calib_model());
       i += 1;
       // width, 2
       bytes::_to_data(params.in_left->width, data + i);