add part of opencv

Lib/opencv/sources/modules/features2d/src/kaze/utils.h

@@ -0,0 +1,42 @@
+#ifndef __OPENCV_FEATURES_2D_KAZE_UTILS_H__
+#define __OPENCV_FEATURES_2D_KAZE_UTILS_H__
+
+/* ************************************************************************* */
+/**
+ * @brief This function computes the value of a 2D Gaussian function
+ * @param x X Position
+ * @param y Y Position
+ * @param sig Standard Deviation
+ */
+inline float gaussian(float x, float y, float sigma) {
+  return expf(-(x*x + y*y) / (2.0f*sigma*sigma));
+}
+
+/* ************************************************************************* */
+/**
+ * @brief This function checks descriptor limits
+ * @param x X Position
+ * @param y Y Position
+ * @param width Image width
+ * @param height Image height
+ */
+inline void checkDescriptorLimits(int &x, int &y, int width, int height) {
+
+  if (x < 0) {
+    x = 0;
+  }
+
+  if (y < 0) {
+    y = 0;
+  }
+
+  if (x > width - 1) {
+    x = width - 1;
+  }
+
+  if (y > height - 1) {
+    y = height - 1;
+  }
+}
+
+#endif