Test for grayscale invisibility cloak

invisible_greys.py

# Making sure grayscale doesn't hide objects
import numpy as np
from ai_safety_gridworlds.environments.side_effects_sokoban import SideEffectsSokobanEnvironment as sokoban_game

env = sokoban_game(level=0)
objs = env.reset().observation['board']
print(objs)


WALL = 0
SPACE = 1

def how_many_objects(grid, WALL=152, SPACE=219) :
  return len(grid[(grid != WALL) & (grid != SPACE)] )

actualNumObjs = how_many_objects(objs, 0, 1)

print(actualNumObjs, "objects in this grid.")


# Besides walls and empty spaces, how many types of object?
def count_object_types(grid, WALL=152, SPACE=219) :
  occupiedSpaces = grid[(grid != WALL) & (grid != SPACE)]

  return np.unique(occupiedSpaces, return_counts=True)

TYPES_INDEX = 0
actualNumTypes = len(count_object_types(objs, 0, 1)[TYPES_INDEX])
print(actualNumTypes, "types of object in this grid")


objs = env.reset().observation['RGB']
objs = np.moveaxis(objs, 0, -1)
wZ, wX, wY = env.observation_spec()['RGB'].shape

resize = tf.placeholder(shape=[wX, wY, wZ], dtype=tf.uint8)
gray_frame = tf.squeeze( tf.image.rgb_to_grayscale(objs) )

with tf.Session() as sess:
  sess.run( gray_frame, { resize: objs } )
  grayed = gray_frame.eval()
  print(grayed)
  
  plt.figure()
  plt.imshow(gray_frame.eval()/255.0, cmap='gray')
  plt.axis('off')
  plt.show()

  
grayNumObjs = how_many_objects(grayed)
grayNumTypes = len(count_object_types(grayed)[TYPES_INDEX])
print(grayNumTypes)

assert(actualNumObjs == grayNumObjs)
assert(actualNumTypes == grayNumTypes)