modified data matrix detection interface (that does not use any new data structures). Added Python sample for data matrix detection. Ticket #1664

samples/python2/video_dmtx.py

@@ -0,0 +1,68 @@
+help='''
+Data matrix detector sample.
+Usage:
+   video_dmtx {<video device number>|<video file name>}
+
+   Generate a datamatrix from  from http://datamatrix.kaywa.com/ and print it out.
+   NOTE: This only handles data matrices, generated for text strings of max 3 characters
+
+   Resize the screen to be large enough for your camera to see, and it should find an read it.
+   
+Keyboard shortcuts:
+
+   q or ESC - exit
+   space - save current image as datamatrix<frame_number>.jpg
+'''
+
+import cv2
+import numpy as np
+import sys
+
+def data_matrix_demo(cap):
+    window_name = "Data Matrix Detector"
+    frame_number = 0
+    need_to_save = False
+    
+    while 1:
+        ret, frame = cap.read()
+        if not ret:
+            break
+            
+        gray = cv2.cvtColor(frame, cv2.COLOR_RGB2GRAY)
+        codes, corners, dmtx = cv2.findDataMatrix(gray)
+        
+        cv2.drawDataMatrixCodes(frame, codes, corners)
+        cv2.imshow(window_name, frame)
+        
+        key = cv2.waitKey(30)
+        c = chr(key & 255)
+        if c in ['q', 'Q', chr(27)]:
+            break
+            
+        if c == ' ':
+            need_to_save = True
+            
+        if need_to_save and codes:
+            filename = ("datamatrix%03d.jpg" % frame_number)
+            cv2.imwrite(filename, frame)
+            print "Saved frame to " + filename
+            need_to_save = False
+            
+        frame_number += 1
+
+
+if __name__ == '__main__':
+    print help
+
+    if len(sys.argv) == 1:
+        cap = cv2.VideoCapture(0)
+    else:
+        cap = cv2.VideoCapture(sys.argv[1])
+        if not cap.isOpened():
+            cap = cv2.VideoCapture(int(sys.argv[1]))
+        
+    if not cap.isOpened():
+        print 'Cannot initialize video capture'
+        sys.exit(-1)
+        
+    data_matrix_demo(cap)