Source code for stable_baselines3.common.vec_env.vec_video_recorder

import os
from typing import Callable

from gym.wrappers.monitoring import video_recorder

from stable_baselines3.common.vec_env.base_vec_env import VecEnv, VecEnvObs, VecEnvStepReturn, VecEnvWrapper
from stable_baselines3.common.vec_env.dummy_vec_env import DummyVecEnv
from stable_baselines3.common.vec_env.subproc_vec_env import SubprocVecEnv

[docs]class VecVideoRecorder(VecEnvWrapper): """ Wraps a VecEnv or VecEnvWrapper object to record rendered image as mp4 video. It requires ffmpeg or avconv to be installed on the machine. :param venv: :param video_folder: Where to save videos :param record_video_trigger: Function that defines when to start recording. The function takes the current number of step, and returns whether we should start recording or not. :param video_length: Length of recorded videos :param name_prefix: Prefix to the video name """ def __init__( self, venv: VecEnv, video_folder: str, record_video_trigger: Callable[[int], bool], video_length: int = 200, name_prefix: str = "rl-video", ): VecEnvWrapper.__init__(self, venv) self.env = venv # Temp variable to retrieve metadata temp_env = venv # Unwrap to retrieve metadata dict # that will be used by gym recorder while isinstance(temp_env, VecEnvWrapper): temp_env = temp_env.venv if isinstance(temp_env, DummyVecEnv) or isinstance(temp_env, SubprocVecEnv): metadata = temp_env.get_attr("metadata")[0] else: metadata = temp_env.metadata self.env.metadata = metadata self.record_video_trigger = record_video_trigger self.video_recorder = None self.video_folder = os.path.abspath(video_folder) # Create output folder if needed os.makedirs(self.video_folder, exist_ok=True) self.name_prefix = name_prefix self.step_id = 0 self.video_length = video_length self.recording = False self.recorded_frames = 0
[docs] def reset(self) -> VecEnvObs: obs = self.venv.reset() self.start_video_recorder() return obs
def start_video_recorder(self) -> None: self.close_video_recorder() video_name = f"{self.name_prefix}-step-{self.step_id}-to-step-{self.step_id + self.video_length}" base_path = os.path.join(self.video_folder, video_name) self.video_recorder = video_recorder.VideoRecorder( env=self.env, base_path=base_path, metadata={"step_id": self.step_id} ) self.video_recorder.capture_frame() self.recorded_frames = 1 self.recording = True def _video_enabled(self) -> bool: return self.record_video_trigger(self.step_id)
[docs] def step_wait(self) -> VecEnvStepReturn: obs, rews, dones, infos = self.venv.step_wait() self.step_id += 1 if self.recording: self.video_recorder.capture_frame() self.recorded_frames += 1 if self.recorded_frames > self.video_length: print(f"Saving video to {self.video_recorder.path}") self.close_video_recorder() elif self._video_enabled(): self.start_video_recorder() return obs, rews, dones, infos
def close_video_recorder(self) -> None: if self.recording: self.video_recorder.close() self.recording = False self.recorded_frames = 1
[docs] def close(self) -> None: VecEnvWrapper.close(self) self.close_video_recorder()
def __del__(self): self.close()