added policy_adaption

environments/policy_adaption/natural_rl_environment/matting.py

@@ -0,0 +1,32 @@
+# Copyright (c) Facebook, Inc. and its affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the license found in the
+# LICENSE file in the root directory of this source tree.
+
+
+class BackgroundMatting(object):
+    """
+    Produce a mask of a given image which will be replaced by natural signals.
+    """
+    def get_mask(self, img):
+        """
+        Take an image of [H, W, 3]. Returns a mask of [H, W]
+        """
+        raise NotImplementedError()
+
+
+class BackgroundMattingWithColor(BackgroundMatting):
+    """
+    Produce a mask by masking the given color. This is a simple strategy
+    but effective for many games.
+    """
+    def __init__(self, color):
+        """
+        Args:
+            color: a (r, g, b) tuple
+        """
+        self._color = color
+
+    def get_mask(self, img):
+        return img == self._color