Add color option to python script

python/pi-motion-lite.py

@@ -8,20 +8,31 @@
 from fractions import Fraction
 import argparse
 
+def parse_color(string):
+    colorMap = {'R': 0, 'G': 1, 'B': 2}
+    if colorMap.has_key(string):
+        return colorMap[string]
+    else:
+        msg = "%r is not a valid value. Please insert one of R G B" % string
+        raise argparse.ArgumentTypeError(msg)
+
+
 parser = argparse.ArgumentParser()
 parser.add_argument("-t", "--threshold", type=int, help="How Much a pixel has to change (default: 10)", default=10)
 parser.add_argument("-s", "--sensitivity", type=int, help="How Many pixels need to change for motion detection (default: 200)", default=200)
 parser.add_argument("-n", "--night", help="Set this if the script is running during the night", action="store_true")
+parser.add_argument("-c", "--color", help="Pixel differences are computed using one of the RGB values for that pixel (defaults: G)", type=parse_color)
 args = parser.parse_args()
 
 #Constants
-SECONDS2MICRO = 1000000  # Constant for converting Shutter Speed in Seconds to Microseconds
+SECONDS2MICRO = 1000000         # Constant for converting Shutter Speed in Seconds to Microseconds
 
-verbose = True			# Display showMessage if True
+verbose = True			        # Display showMessage if True
 threshold = args.threshold      # How Much a pixel has to change
 sensitivity = args.sensitivity  # How Many pixels need to change for motion detection
-nightShut = 5.5   	        # seconds Night shutter Exposure Time default = 5.5  Do not exceed 6 since camera may lock up
+nightShut = 5.5   	            # seconds Night shutter Exposure Time default = 5.5  Do not exceed 6 since camera may lock up
 nightISO = 800
+print args.color
 
 testWidth = 100
 testHeight = 75