Add Prod transform, Add test_factory

lerobot/common/envs/factory.py

@@ -2,6 +2,7 @@ from torchrl.envs.transforms import StepCounter, TransformedEnv
 
 from lerobot.common.envs.pusht import PushtEnv
 from lerobot.common.envs.simxarm import SimxarmEnv
+from lerobot.common.envs.transforms import Prod
 
 
 def make_env(cfg):
@@ -25,6 +26,10 @@ def make_env(cfg):
     # limit rollout to max_steps
     env = TransformedEnv(env, StepCounter(max_steps=cfg.episode_length))
 
+    if cfg.env == "pusht":
+        # to ensure pusht is in [0,255] like simxarm
+        env.append_transform(Prod(in_keys=[("observation", "image")], prod=255.0))
+
     return env