Started overall project refactoring

1. Git will now be ignoring files whose names start with `exp_`.
   If you want to do quick experimenting but are not ready to add
   such files to repository, name them starting with `exp_`. For
   example `exp_cool_motion.py`.
2  Use the file `nao_defaults.json` to store the global project
   settings (such as IP address of the robot, or our preferred
   resolution). In your scripts make sure to load the default
   values from that file if needed (i.e. do NOT hard-code any
   configuration in your scripts). `nao_defaults.json` is a file
   with the stable config. If you need to experiment with configs,
   create a file `exp_config.json`.
3. Colorpicker is now a saner tool (you can specify output width, and
   the default IP address of the nao is pulled from the JSON config
   file).

.gitignore

@@ -1,3 +1,5 @@
 *.sw*
 *.pyc
 *.jpg
+~*~
+exp_*

scripts/color_calibration.txt

@@ -1,7 +0,0 @@
-# Optimal HSV for ball detection
-
-# LOW HSV
-0 185 170
-
-# HIGH HSV
-6 255 255

scripts/colorpicker.py

@@ -1,4 +1,5 @@
 from __future__ import print_function
+from __future__ import division
 
 import json
 import argparse
@@ -50,14 +51,17 @@ class Colorpicker(object):
         cv2.setTrackbarPos(name, self.WINDOW_DETECTION_NAME,
                            self.settings[name])
 
-    def show_frame(self, frame):
+    def show_frame(self, frame, width=None):
         frame_HSV = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)
         frame_threshold = cv2.inRange(
             frame_HSV,
             tuple(map(self.settings.get, ('low_h', 'low_s', 'low_v'))),
             tuple(map(self.settings.get, ('high_h', 'high_s', 'high_v')))
         )
-        frame_threshold = cv2.resize(frame_threshold, (640, 480))
+        if width:
+            sf = width / frame.shape[1]
+            frame = cv2.resize(frame, (0, 0), fx=sf, fy=sf)
+            frame_threshold = cv2.resize(frame_threshold, (0, 0), fx=sf, fy=sf)
         cv2.imshow(self.WINDOW_CAPTURE_NAME, frame)
         cv2.imshow(self.WINDOW_DETECTION_NAME, frame_threshold)
         return cv2.waitKey(1)
@@ -75,9 +79,14 @@ class Colorpicker(object):
 
 
 if __name__ == '__main__':
+
+    with open('nao_defaults.json') as f:
+        defaults = json.load(f)
+
     parser = argparse.ArgumentParser(
-    epilog='When called without arguments specifying the video source, ' +
-    'will try to use the webcam')
+        epilog='When called without arguments specifying the video source, ' +
+        'will try to use the webcam'
+    )
     parser.add_argument(
         '-o', '--output-config',
         help='file, to which the settings will be saved (if given)'
@@ -86,43 +95,52 @@ if __name__ == '__main__':
         '-i', '--input-config',
         help='file, from which to read the initial values'
     )
-    parser.add_argument(
+    imsource = parser.add_mutually_exclusive_group()
+    imsource.add_argument(
         '--video-file',
         help='video file to use'
     )
-    parser.add_argument(
+    imsource.add_argument(
         '--image-file',
         help='image to use'
     )
+    imsource.add_argument(
+        '--nao-ip',
+        help='ip address of the nao robot, from which to capture',
+        default=False,
+        const=defaults['ip'],
+        nargs='?'
+    )
     parser.add_argument(
         '--still',
         help='only take one image from video stream',
         action='store_true'
     )
-    parser.add_argument(
-        '--nao-ip',
-        help='ip address of the nao robot, from which to capture'
-    )
     parser.add_argument(
         '--nao-cam',
-        choices=['upper', 'lower'],
-        help='choose a camera from nao'
+        choices=[0, 1],
+        help='0 for top camera, 1 for bottom camera',
+        default=defaults['cam']
     )
     parser.add_argument(
         '--nao-res',
         choices=[1, 2, 3],
+        help='choose a nao resolution',
         type=int,
-        default=1
+        default=defaults['res']
+    )
+    parser.add_argument(
+        '--width',
+        help='specify width of the image output',
+        type=int,
+        default=640
     )
     args = parser.parse_args()
 
     cp = Colorpicker()
-    camera_ids = {
-        'upper': 0,
-        'lower': 1
-    }
     if args.input_config:
         cp.load(args.input_config)
+
     if args.video_file:
         rdr = VideoReader(args.video_file, loop=True)
     elif args.image_file:
@@ -130,22 +148,25 @@ if __name__ == '__main__':
     elif args.nao_ip:
         rdr = NaoImageReader(
             args.nao_ip,
-            cam_id=camera_ids[args.nao_cam] if args.nao_cam else 0,
+            cam_id=args.nao_cam,
             res=args.nao_res
         )
     else:
         rdr = VideoReader(0)
+
     try:
         if args.still:
             frame = rdr.get_frame()
+            rdr.close()
         while True:
             if not args.still:
                 frame = rdr.get_frame()
-            key = cp.show_frame(frame)
+            key = cp.show_frame(frame, args.width)
             if key == ord('q') or key == 27:
                 break
     finally:
         cp.do_print()
         if args.output_config:
             cp.save(args.output_config)
-        rdr.close()
+        if not args.still:
+            rdr.close()

scripts/nao_defaults.json

@@ -0,0 +1,6 @@
+{
+    "ip": "192.168.0.11",
+    "res": 1,
+    "port": 9559,
+    "cam": 0
+}