CCTV Digital Video Recorder Systems
A digital video recorder (DVR), sometimes referred to by the merchandising term personal video recorder (PVR), is a consumer electronics device or application software that records video in a digital format to a disk drive, USB flash drive, SD memory card or other local or networked mass storage device.
The term includes set-top boxes (STB) with direct to disk recording facility, portable media players (PMP) with recording, recorders (PMR) as camcorders that record onto Secure Digital memory cards and software for personal computers which enables video capture and playback to and from a hard disk drive.
Network Video Recorder Systems
A network video recorder (NVR) is a software program that records video in a digital format to a disk drive, USB flash drive, SD memory card or other mass storage device. An NVR contains no dedicated video capture hardware. However, the software is typically run on a dedicated device, usually with an embedded operating system.
Network video recorders are distinct from digital video recorders as their input is from a network rather than a direct connection to a video capture card or tuner. Video on a DVR is encoded and processed at the DVR, while video on an NVR is encoded and processed at the camera, then streamed to the NVR for storage or remote viewing.NVR is used in IP video surveillance systems.