More appropriate name, image_capture.  Use /dev/video0.  Store last image

Change-Id: I52c070162c5a075ca43b1e676264496ad024e0ff
diff --git a/y2020/vision/tools/python_code/image_capture.py b/y2020/vision/tools/python_code/image_capture.py
new file mode 100644
index 0000000..d6ce6d7
--- /dev/null
+++ b/y2020/vision/tools/python_code/image_capture.py
@@ -0,0 +1,34 @@
+import cv2
+import datetime
+# Open the device at the ID X for /dev/videoX
+CAMERA_INDEX = 0
+cap = cv2.VideoCapture(CAMERA_INDEX)
+
+#Check whether user selected camera is opened successfully.
+if not (cap.isOpened()):
+    print("Could not open video device /dev/video%d" % CAMERA_INDEX)
+    quit()
+
+while True:
+    # Capture frame-by-frame
+    ret, frame = cap.read()
+
+    exp = cap.get(cv2.CAP_PROP_EXPOSURE)
+    #print("Exposure:", exp)
+    # Display the resulting frame
+    cv2.imshow('preview', frame)
+
+    #Waits for a user input to capture image or quit the application
+    keystroke = cv2.waitKey(1)
+
+    if keystroke & 0xFF == ord('q'):
+        break
+    elif keystroke & 0xFF == ord('c'):
+        image_name = datetime.datetime.today().strftime(
+            "capture-%Y-%m-%d-%H-%M-%S.png")
+        print("Capturing image as %s" % image_name)
+        cv2.imwrite(image_name, frame)
+
+# When everything's done, release the capture
+cap.release()
+cv2.destroyAllWindows()
diff --git a/y2020/vision/tools/python_code/usb_camera_stream.py b/y2020/vision/tools/python_code/usb_camera_stream.py
deleted file mode 100644
index 5d3ae91..0000000
--- a/y2020/vision/tools/python_code/usb_camera_stream.py
+++ /dev/null
@@ -1,25 +0,0 @@
-import cv2
-# Open the device at the ID X for /dev/videoX
-cap = cv2.VideoCapture(2)
-
-#Check whether user selected camera is opened successfully.
-if not (cap.isOpened()):
-    print("Could not open video device")
-    quit()
-
-while True:
-    # Capture frame-by-frame
-    ret, frame = cap.read()
-
-    exp = cap.get(cv2.CAP_PROP_EXPOSURE)
-    print("Exposure:", exp)
-    # Display the resulting frame
-    cv2.imshow('preview', frame)
-
-    #Waits for a user input to quit the application
-    if cv2.waitKey(1) & 0xFF == ord('q'):
-        break
-
-# When everything done, release the capture
-cap.release()
-cv2.destroyAllWindows()