Htedvs/r-h4d stand-alone dvr Htedvs/r-h4d embedded stand-alone dvr has the features of strong network function of htdvs network video server for remote configuration and transmission but mini exterior for flexible installation and of the advantages of htedvs/r embedded stand-alone dvr with rtos realtime operation system and local recording, with mpeg4/h.264 video compression, g.729a audio compression; single-channel audio and 4 channels video input, viewing 4channels non real time video at the same single-channel video and audio output; built-in 2.5 inches hard disk for recording; usb2.0 interface and nas storage mode; 6 alarm interfaces can be set to be inputs or outputs optionally, transparency i/o interfaces as well (aux i/o).