diff --git a/doc/Doxyfile.in b/doc/Doxyfile.in
index b27593764..dd1edd64a 100644
--- a/doc/Doxyfile.in
+++ b/doc/Doxyfile.in
@@ -119,7 +119,7 @@ REFERENCES_LINK_SOURCE = YES
 SOURCE_TOOLTIPS        = YES
 USE_HTAGS              = NO
 VERBATIM_HEADERS       = NO
-ALPHABETICAL_INDEX     = NO
+ALPHABETICAL_INDEX     = YES
 COLS_IN_ALPHA_INDEX    = 5
 IGNORE_PREFIX          =
 GENERATE_HTML          = YES
diff --git a/modules/core/include/opencv2/core/cuda.hpp b/modules/core/include/opencv2/core/cuda.hpp
index 218ebd86f..5564807fe 100644
--- a/modules/core/include/opencv2/core/cuda.hpp
+++ b/modules/core/include/opencv2/core/cuda.hpp
@@ -51,15 +51,6 @@
 #include "opencv2/core.hpp"
 #include "opencv2/core/cuda_types.hpp"
 
-/**
-  @addtogroup cuda
-  @{
-    @defgroup cuda_init Initalization and Information
-    @defgroup cuda_struct Data Structures
-    @defgroup cuda_calib3d Camera Calibration and 3D Reconstruction
-  @}
- */
-
 namespace cv { namespace cuda {
 
 //! @addtogroup cuda_struct
diff --git a/modules/cuda/include/opencv2/cuda.hpp b/modules/cuda/include/opencv2/cuda.hpp
index 1937987db..67d4fdd85 100644
--- a/modules/cuda/include/opencv2/cuda.hpp
+++ b/modules/cuda/include/opencv2/cuda.hpp
@@ -53,6 +53,9 @@
 @defgroup cuda CUDA-accelerated Computer Vision
     @ref cuda_intro "Introduction page"
     @{
+        @defgroup cuda_init Initalization and Information
+        @defgroup cuda_struct Data Structures
+        @defgroup cuda_calib3d Camera Calibration and 3D Reconstruction
         @defgroup cuda_objdetect Object Detection
     @}