Recording devices make use of digital technology to record video and audio which can be replayed and analyzed in various ways on television, PC monitors, or inside web browsers. Examples include audio recording devices, voice recording devices, and phone recording devices. Digital video recorders, security DVR, have fast become popular, with multiple features and functions.
DVR: Digital Video Recorders
A digital video recorder can record video and audio signals in the "mpeg" format. This does away with older magnetic tapes and recordings with poor quality. The recorded files can be watched on monitors, or transferred to CDs with in-built CD writers. Some DVRs even allow viewing the files directly using a web browser and an Internet connection.
Using a DVR:
A DVR can be an independent unit with all of the features above, or it could be inserted as a card inside the PC. This gives greater flexibility. The card can be used to record television programs, or camera feeds. Multiple cameras can be used with a multi-channel DVR such as a 4-channel DVR.
A DVR card can also be used to record television programs, and directv DVR allows one to do just that as a stand alone DVR unit. There are also products with embedded DVR placed inside, and DVR players. HDTV DVR is also a separate option.
The great convenience of using DVR surveillance is the manipulation of the recorded feed that it allows. One need not fast forward the whole tape as the case used to be. Timings, events, alerts can be used to reach the appropriate points on the recorded feed. The images can be seen as individual pictures, and either captured on the screen or printed out.
Spy Recording Devices
There are laws against spy recording, especially phone conversations. The devices therefore need to be used with legitimate aims. A spy recording device could come in the shape of a pen, watch, wall clock, lighter, a book, and so on. The power is derived from button cells, and images and files can be transferred to desktops and other devices. There are limitations on picture quality and the amount of file storage. Many devices have auto recording and auto power off features.