samples: fix python samples compatibility with demo.py

samples/python/dis_opt_flow.py

@@ -18,6 +18,7 @@ from __future__ import print_function
 
 import numpy as np
 import cv2 as cv
+
 import video
 
 
@@ -56,7 +57,7 @@ def warp_flow(img, flow):
     return res
 
 
-if __name__ == '__main__':
+def main():
     import sys
     print(__doc__)
     try:
@@ -111,4 +112,11 @@ if __name__ == '__main__':
         if ch == ord('4'):
             use_temporal_propagation = not use_temporal_propagation
             print('temporal propagation is', ['off', 'on'][use_temporal_propagation])
+
+    print('Done')
+
+
+if __name__ == '__main__':
+    print(__doc__)
+    main()
     cv.destroyAllWindows()

samples/python/stitching.py

@@ -8,15 +8,18 @@ Show how to use Stitcher API from python in a simple way to stitch panoramas
 or scans.
 '''
 
+# Python 2/3 compatibility
 from __future__ import print_function
-import cv2 as cv
+
 import numpy as np
+import cv2 as cv
+
 import argparse
 import sys
 
 modes = (cv.Stitcher_PANORAMA, cv.Stitcher_SCANS)
 
-parser = argparse.ArgumentParser(description='Stitching sample.')
+parser = argparse.ArgumentParser(prog='stitching.py', description='Stitching sample.')
 parser.add_argument('--mode',
     type = int, choices = modes, default = cv.Stitcher_PANORAMA,
     help = 'Determines configuration of stitcher. The default is `PANORAMA` (%d), '
@@ -25,23 +28,35 @@ parser.add_argument('--mode',
 parser.add_argument('--output', default = 'result.jpg',
     help = 'Resulting image. The default is `result.jpg`.')
 parser.add_argument('img', nargs='+', help = 'input images')
-args = parser.parse_args()
-
-# read input images
-imgs = []
-for img_name in args.img:
-    img = cv.imread(img_name)
-    if img is None:
-        print("can't read image " + img_name)
+
+__doc__ += '\n' + parser.format_help()
+
+def main():
+    args = parser.parse_args()
+
+    # read input images
+    imgs = []
+    for img_name in args.img:
+        img = cv.imread(cv.samples.findFile(img_name))
+        if img is None:
+            print("can't read image " + img_name)
+            sys.exit(-1)
+        imgs.append(img)
+
+    stitcher = cv.Stitcher.create(args.mode)
+    status, pano = stitcher.stitch(imgs)
+
+    if status != cv.Stitcher_OK:
+        print("Can't stitch images, error code = %d" % status)
         sys.exit(-1)
-    imgs.append(img)
 
-stitcher = cv.Stitcher.create(args.mode)
-status, pano = stitcher.stitch(imgs)
+    cv.imwrite(args.output, pano);
+    print("stitching completed successfully. %s saved!" % args.output)
+
+    print('Done')
 
-if status != cv.Stitcher_OK:
-    print("Can't stitch images, error code = %d" % status)
-    sys.exit(-1)
 
-cv.imwrite(args.output, pano);
-print("stitching completed successfully. %s saved!" % args.output)
+if __name__ == '__main__':
+    print(__doc__)
+    main()
+    cv.destroyAllWindows()