... algorithm ideal for standalone DVR2)4 channels Realtime full D1 recording, and real time multi channels playback3).Support VGA output and TV ... ,snapshot & FTPAudioAudio CompressionG711ABidrectional TalkSupportRecord &PlaybackRecording ModeManual>Alarm>Video Detection>ContinuousPlaybackMulti channels playback simultaneously,pause,stop,rewind,fast play, slow play,next ...