import numpy as np
import cv2
from gym.spaces import Box
from gym import ObservationWrapper
[docs]class GrayScaleObservation(ObservationWrapper):
r"""Convert the image observation from RGB to gray scale. """
def __init__(self, env, keep_dim=False):
super().__init__(env)
self.keep_dim = keep_dim
obs_shape = self.observation_space.shape[:2]
if self.keep_dim:
self.observation_space = Box(low=0, high=255, shape=(*obs_shape, 1), dtype=np.uint8)
else:
self.observation_space = Box(low=0, high=255, shape=obs_shape, dtype=np.uint8)
def observation(self, observation):
observation = cv2.cvtColor(observation, cv2.COLOR_RGB2GRAY)
if self.keep_dim:
observation = np.expand_dims(observation, -1)
return observation