diff --git a/grayMatch.cpp b/grayMatch.cpp
index fd9a2b1..72cbabb 100644
--- a/grayMatch.cpp
+++ b/grayMatch.cpp
@@ -786,7 +786,7 @@ Model_t trainModel(const unsigned char *data, int width, int height, int channel
 }
 
 void matchModel(const unsigned char *data, int width, int height, int channels, int bytesPerLine,
-                int roiLeft, int roiTop, int roiWidth, int roiHeight, const Model *model,
+                int roiLeft, int roiTop, int roiWidth, int roiHeight, const Model_t model,
                 int *count, Pose *poses, int level, double startAngle, double spanAngle,
                 double maxOverlap, double minScore, int subpixel) {
     if (nullptr == count) {
diff --git a/grayMatch.h b/grayMatch.h
index a96a60a..c96f0e2 100644
--- a/grayMatch.h
+++ b/grayMatch.h
@@ -55,7 +55,7 @@ API_PUBLIC Model_t trainModel(const unsigned char *data, int width, int height,
  */
 API_PUBLIC void matchModel(const unsigned char *data, int width, int height, int channels,
                            int bytesPerLine, int roiLeft, int roiTop, int roiWidth, int roiHeight,
-                           const Model* model, int *count, Pose *poses, int level,
+                           const Model_t model, int *count, Pose *poses, int level,
                            double startAngle, double spanAngle, double maxOverlap, double minScore,
                            int subpixel);
 
@@ -64,7 +64,7 @@ API_PUBLIC void matchModel(const unsigned char *data, int width, int height, int
  * @param model
  * @return pyramid level
  */
-API_PUBLIC int modelLevel(const Model* model);
+API_PUBLIC int modelLevel(const Model_t model);
 
 /**
  * @brief get trained model image
@@ -77,7 +77,7 @@ API_PUBLIC int modelLevel(const Model* model);
  * @param channels image channels, can input nullptr
  * @return
  */
-API_PUBLIC void modelImage(const Model* model, int level, unsigned char *data, int length,
+API_PUBLIC void modelImage(const Model_t model, int level, unsigned char *data, int length,
                            int *width, int *height, int *channels);
 
 /**
@@ -94,7 +94,7 @@ API_PUBLIC void freeModel(Model_t *model);
  * @param size in(buffer size)/out(written size)
  * @return true(success)false(failed)
  */
-API_PUBLIC bool serialize(const Model* model, unsigned char *buffer, int *size);
+API_PUBLIC bool serialize(const Model_t model, unsigned char *buffer, int *size);
 
 /**
  * @brief deserialize model
diff --git a/serialize.cpp b/serialize.cpp
index 65158d6..dc9debd 100644
--- a/serialize.cpp
+++ b/serialize.cpp
@@ -187,7 +187,7 @@ void operation(Buffer *buf, Model &model) {
     (*buf) & (model);
 }
 
-bool serialize(Model *const model, unsigned char *buffer, int *size) {
+bool serialize(const Model_t model, unsigned char *buffer, int *size) {
     if (nullptr == size) {
         return false;
     }