diff --git a/modules/aruco/include/opencv2/aruco/dictionary.hpp b/modules/aruco/include/opencv2/aruco/dictionary.hpp
index 36a3a27ad..52bcf6772 100644
--- a/modules/aruco/include/opencv2/aruco/dictionary.hpp
+++ b/modules/aruco/include/opencv2/aruco/dictionary.hpp
@@ -51,6 +51,12 @@ namespace aruco {
 /**
  * @brief Dictionary/Set of markers. It contains the inner codification
  *
+ * bytesList contains the marker codewords where
+ * - bytesList.rows is the dictionary size
+ * - each marker is encoded using `nbytes = ceil(markerSize*markerSize/8.)`
+ * - each row contains all 4 rotations of the marker, so its length is `4*nbytes`
+ *
+ * `bytesList.ptr(i)[k*nbytes + j]` is then the j-th byte of i-th marker, in its k-th rotation.
  */
 class CV_EXPORTS Dictionary {
 
@@ -62,8 +68,7 @@ class CV_EXPORTS Dictionary {
 
     /**
       */
-    Dictionary(const unsigned char *bytes = 0, int _markerSize = 0, int dictsize = 0,
-               int _maxcorr = 0);
+    Dictionary(const Mat &_bytesList = Mat(), int _markerSize = 0, int _maxcorr = 0);
 
 
 
diff --git a/modules/aruco/src/dictionary.cpp b/modules/aruco/src/dictionary.cpp
index f7eba518d..c1d9d68e0 100644
--- a/modules/aruco/src/dictionary.cpp
+++ b/modules/aruco/src/dictionary.cpp
@@ -38,9 +38,9 @@ the use of this software, even if advised of the possibility of such damage.
 
 #include "precomp.hpp"
 #include "opencv2/aruco/dictionary.hpp"
-#include "predefined_dictionaries.cpp"
 #include <opencv2/core.hpp>
 #include <opencv2/imgproc.hpp>
+#include "predefined_dictionaries.hpp"
 
 
 namespace cv {
@@ -50,16 +50,10 @@ using namespace std;
 
 /**
   */
-Dictionary::Dictionary(const unsigned char *bytes, int _markerSize, int dictsize, int _maxcorr) {
+Dictionary::Dictionary(const Mat &_bytesList, int _markerSize, int _maxcorr) {
     markerSize = _markerSize;
     maxCorrectionBits = _maxcorr;
-    int nbytes = (markerSize * markerSize) / 8;
-    if((markerSize * markerSize) % 8 != 0) nbytes++;
-
-    // save bytes in internal format
-    // bytesList.ptr(i)[k*nbytes + j] is j-th byte of i-th marker, in its k-th rotation
-    bytesList = Mat(dictsize, nbytes, CV_8UC4);
-    memcpy(bytesList.data, bytes, dictsize*nbytes*4);
+    bytesList = _bytesList;
 }
 
 
@@ -102,10 +96,7 @@ bool Dictionary::identify(const Mat &onlyBits, int &idx, int &rotation,
         }
     }
 
-    if(idx != -1)
-        return true;
-    else
-        return false;
+    return idx != -1;
 }
 
 
@@ -167,9 +158,8 @@ void Dictionary::drawMarker(int id, int sidePixels, OutputArray _img, int border
   * @brief Transform matrix of bits to list of bytes in the 4 rotations
   */
 Mat Dictionary::getByteListFromBits(const Mat &bits) {
-
-    int nbytes = (bits.cols * bits.rows) / 8;
-    if((bits.cols * bits.rows) % 8 != 0) nbytes++;
+    // integer ceil
+    int nbytes = (bits.cols * bits.rows + 8 - 1) / 8;
 
     Mat candidateByteList(1, nbytes, CV_8UC4, Scalar::all(0));
     unsigned char currentBit = 0;
@@ -246,27 +236,27 @@ Mat Dictionary::getBitsFromByteList(const Mat &byteList, int markerSize) {
 
 
 // DictionaryData constructors calls
-const Dictionary DICT_ARUCO_DATA = Dictionary(&(DICT_ARUCO_BYTES[0][0][0]), 5, 1024, 0);
+const Dictionary DICT_ARUCO_DATA = Dictionary(Mat(1024, (5*5 + 7)/8, CV_8UC4, (uchar*)DICT_ARUCO_BYTES), 5, 0);
 
-const Dictionary DICT_4X4_50_DATA = Dictionary(&(DICT_4X4_1000_BYTES[0][0][0]), 4, 50, 1);
-const Dictionary DICT_4X4_100_DATA = Dictionary(&(DICT_4X4_1000_BYTES[0][0][0]), 4, 100, 1);
-const Dictionary DICT_4X4_250_DATA = Dictionary(&(DICT_4X4_1000_BYTES[0][0][0]), 4, 250, 1);
-const Dictionary DICT_4X4_1000_DATA = Dictionary(&(DICT_4X4_1000_BYTES[0][0][0]), 4, 1000, 0);
+const Dictionary DICT_4X4_50_DATA = Dictionary(Mat(50, (4*4 + 7)/8, CV_8UC4, (uchar*)DICT_4X4_1000_BYTES), 4, 1);
+const Dictionary DICT_4X4_100_DATA = Dictionary(Mat(100, (4*4 + 7)/8, CV_8UC4, (uchar*)DICT_4X4_1000_BYTES), 4, 1);
+const Dictionary DICT_4X4_250_DATA = Dictionary(Mat(250, (4*4 + 7)/8, CV_8UC4, (uchar*)DICT_4X4_1000_BYTES), 4, 1);
+const Dictionary DICT_4X4_1000_DATA = Dictionary(Mat(1000, (4*4 + 7)/8, CV_8UC4, (uchar*)DICT_4X4_1000_BYTES), 4, 0);
 
-const Dictionary DICT_5X5_50_DATA = Dictionary(&(DICT_5X5_1000_BYTES[0][0][0]), 5, 50, 3);
-const Dictionary DICT_5X5_100_DATA = Dictionary(&(DICT_5X5_1000_BYTES[0][0][0]), 5, 100, 3);
-const Dictionary DICT_5X5_250_DATA = Dictionary(&(DICT_5X5_1000_BYTES[0][0][0]), 5, 250, 2);
-const Dictionary DICT_5X5_1000_DATA = Dictionary(&(DICT_5X5_1000_BYTES[0][0][0]), 5, 1000, 2);
+const Dictionary DICT_5X5_50_DATA = Dictionary(Mat(50, (5*5 + 7)/8, CV_8UC4, (uchar*)DICT_5X5_1000_BYTES), 5, 3);
+const Dictionary DICT_5X5_100_DATA = Dictionary(Mat(100, (5*5 + 7)/8, CV_8UC4, (uchar*)DICT_5X5_1000_BYTES), 5, 3);
+const Dictionary DICT_5X5_250_DATA = Dictionary(Mat(250, (5*5 + 7)/8, CV_8UC4, (uchar*)DICT_5X5_1000_BYTES), 5, 2);
+const Dictionary DICT_5X5_1000_DATA = Dictionary(Mat(1000, (5*5 + 7)/8, CV_8UC4, (uchar*)DICT_5X5_1000_BYTES), 5, 2);
 
-const Dictionary DICT_6X6_50_DATA = Dictionary(&(DICT_6X6_1000_BYTES[0][0][0]), 6, 50, 6);
-const Dictionary DICT_6X6_100_DATA = Dictionary(&(DICT_6X6_1000_BYTES[0][0][0]), 6, 100, 5);
-const Dictionary DICT_6X6_250_DATA = Dictionary(&(DICT_6X6_1000_BYTES[0][0][0]), 6, 250, 5);
-const Dictionary DICT_6X6_1000_DATA = Dictionary(&(DICT_6X6_1000_BYTES[0][0][0]), 6, 1000, 4);
+const Dictionary DICT_6X6_50_DATA = Dictionary(Mat(50, (6*6 + 7)/8 ,CV_8UC4, (uchar*)DICT_6X6_1000_BYTES), 6, 6);
+const Dictionary DICT_6X6_100_DATA = Dictionary(Mat(100, (6*6 + 7)/8 ,CV_8UC4, (uchar*)DICT_6X6_1000_BYTES), 6, 5);
+const Dictionary DICT_6X6_250_DATA = Dictionary(Mat(250, (6*6 + 7)/8 ,CV_8UC4, (uchar*)DICT_6X6_1000_BYTES), 6, 5);
+const Dictionary DICT_6X6_1000_DATA = Dictionary(Mat(1000, (6*6 + 7)/8 ,CV_8UC4, (uchar*)DICT_6X6_1000_BYTES), 6, 4);
 
-const Dictionary DICT_7X7_50_DATA = Dictionary(&(DICT_7X7_1000_BYTES[0][0][0]), 7, 50, 9);
-const Dictionary DICT_7X7_100_DATA = Dictionary(&(DICT_7X7_1000_BYTES[0][0][0]), 7, 100, 8);
-const Dictionary DICT_7X7_250_DATA = Dictionary(&(DICT_7X7_1000_BYTES[0][0][0]), 7, 250, 8);
-const Dictionary DICT_7X7_1000_DATA = Dictionary(&(DICT_7X7_1000_BYTES[0][0][0]), 7, 1000, 6);
+const Dictionary DICT_7X7_50_DATA = Dictionary(Mat(50, (7*7 + 7)/8 ,CV_8UC4, (uchar*)DICT_7X7_1000_BYTES), 7, 9);
+const Dictionary DICT_7X7_100_DATA = Dictionary(Mat(100, (7*7 + 7)/8 ,CV_8UC4, (uchar*)DICT_7X7_1000_BYTES), 7, 8);
+const Dictionary DICT_7X7_250_DATA = Dictionary(Mat(250, (7*7 + 7)/8 ,CV_8UC4, (uchar*)DICT_7X7_1000_BYTES), 7, 8);
+const Dictionary DICT_7X7_1000_DATA = Dictionary(Mat(1000, (7*7 + 7)/8 ,CV_8UC4, (uchar*)DICT_7X7_1000_BYTES), 7, 6);
 
 
 const Dictionary &getPredefinedDictionary(PREDEFINED_DICTIONARY_NAME name) {
diff --git a/modules/aruco/src/predefined_dictionaries.cpp b/modules/aruco/src/predefined_dictionaries.hpp
similarity index 99%
rename from modules/aruco/src/predefined_dictionaries.cpp
rename to modules/aruco/src/predefined_dictionaries.hpp
index 421ee4495..6abc4a5f9 100644
--- a/modules/aruco/src/predefined_dictionaries.cpp
+++ b/modules/aruco/src/predefined_dictionaries.hpp
@@ -36,8 +36,7 @@ or tort (including negligence or otherwise) arising in any way out of
 the use of this software, even if advised of the possibility of such damage.
 */
 
-namespace cv {
-namespace aruco {
+namespace {
 
 
 
@@ -53,7 +52,7 @@ namespace aruco {
   * Each rotation implies a 90 degree rotation of the marker in anticlockwise direction.
   */
 
-const unsigned char DICT_ARUCO_BYTES[][4][4] = {
+static unsigned char DICT_ARUCO_BYTES[][4][4] = {
     { { 132, 33, 8, 0 },
       { 0, 0, 15, 1 },
       { 8, 66, 16, 1 },
@@ -4152,7 +4151,7 @@ const unsigned char DICT_ARUCO_BYTES[][4][4] = {
       { 7, 255, 240, 0 }, },
 };
 
-const unsigned char DICT_4X4_1000_BYTES[][4][2] =
+static unsigned char DICT_4X4_1000_BYTES[][4][2] =
     { { { 181, 50 },
         { 235, 72 },
         { 76, 173 },
@@ -8154,7 +8153,7 @@ const unsigned char DICT_4X4_1000_BYTES[][4][2] =
         { 253, 239 },
         { 219, 255 }, }, };
 
-const unsigned char DICT_5X5_1000_BYTES[][4][4] =
+static unsigned char DICT_5X5_1000_BYTES[][4][4] =
     { { { 162, 217, 94, 0 },
         { 82, 46, 217, 1 },
         { 61, 77, 162, 1 },
@@ -12156,7 +12155,7 @@ const unsigned char DICT_5X5_1000_BYTES[][4][4] =
         { 184, 73, 239, 1 },
         { 204, 238, 57, 1 }, }, };
 
-const unsigned char DICT_6X6_1000_BYTES[][4][5] =
+static unsigned char DICT_6X6_1000_BYTES[][4][5] =
     { { { 30, 61, 216, 42, 6 },
         { 227, 186, 70, 49, 9 },
         { 101, 65, 187, 199, 8 },
@@ -16158,7 +16157,7 @@ const unsigned char DICT_6X6_1000_BYTES[][4][5] =
         { 255, 135, 198, 183, 15 },
         { 174, 219, 251, 231, 3 }, }, };
 
-const unsigned char DICT_7X7_1000_BYTES[][4][7] =
+static unsigned char DICT_7X7_1000_BYTES[][4][7] =
     { { { 221, 92, 108, 165, 202, 10, 1 },
         { 99, 179, 173, 228, 49, 180, 0 },
         { 168, 41, 210, 155, 29, 93, 1 },
@@ -20160,4 +20159,3 @@ const unsigned char DICT_7X7_1000_BYTES[][4][7] =
         { 252, 176, 35, 180, 179, 243, 1 },
         { 31, 47, 190, 169, 27, 97, 1 }, }, };
 }
-}