4 channel h.264 dvr Video Compression:H.264 support VGA, HDMI and USB2.0. Support ... Ω)Output1 channel, BNC(200-3000mV, 5KΩ)DisplayDisplay Split1/4Resolution1920×1080, 1280×1024, 1280×720, 1024×768, 800×600Tour DisplaySupportRecordingVideo/Audio CompressionH.264 ... for mouse control, 1 for backupRS232Dahua keyboard, PC communicationRS485PTZ control 4 channel h.264 dvr