SDI :
Serial Digital Interface (SDI) refers to a family of video interfaces standardized by SMPTE.
SDTV :
Standard-definition TV: traditional television.
SECAM :
Comes from the French "Sequentiel a memoire" which actually describes how the colour is transmitted, by a sequence of chrominance colour signals and the need for a memory device in the TV receiver when decoding the colour information. This is used in France, Russia and some other Eastern European countries. It has 625 horizontal scan lines and 25 frames per second.
Sequential Switcher :
Video Switcher. A device that allows the video signals from multiple cameras to be displayed on a monitor, or recorded on a VCR one at a time in sequence.
Server :
A computer program that provides services to other computer programs in the same or other computers. Or, the computer that a server program runs.
Signal-to-Noise(S/N) Ratio :
The ratio between the television signal and the noise; expressed in decibel(dB). The higher the number the better.
SMPTE :
The Society of Motion Picture and Television Engineers (SMPTE) is an international professional association, based in the United States of America, of engineers working in the motion imaging industries.
SMTP :
Simple Mail Transfer Protocol. TCP/IP used in sending and receiving e-mail.
Switcher :
Sequential Switcher or Video Switcher. A device that allows the video signals from multiple cameras to be displayed on a monitor, or recorded on a VCR one at a time in sequence.
SVHS (Super Video Home System) :
Super VHS; a higher quality extension of the VHS home videotape format.
S-Video :
Transmits luminance and color portions separately, using multiple wires, thus avoiding the color encoding process and its inevitable loss of picture quality.
Sensitivity :
The sensitivity of a camera is often configured on your digital surveillance system.Motion Detection based recording uses relies on the sensitivity of the cameras to trigger recording
Secure Area :
A designated area in which access into and out of is controlled and can be monitored.
Secure Door :
A door in which access through is controlled and can be monitored.
Shielding :
Providing electrical isolation for a circuit, component, or wire by enclosing or isolating the circuit, component, or wire with a metal enclosure, plate, or foil that blocks any interfering electrical field.
Short Circuit :
An unintentional connection that provides a low resistance path between two points in a circuit or between a point in a circuit and ground. A Short Circuit can drastically affect the operation of a circuit. If excessive current flow results from the Short Circuit, a device may be damaged or ruined.
Signature Verification :
A biometric identification method using a person's signature characteristics (writing speed, pen pressure, shape of loops, etc.) to identify that person.
Spike :
A voltage peak of high amplitude and short duration. See Transients.
Smart Card :
An identification card or access control card with a built-in integrated circuit chip. This gives the card microprocessor memory and intelligence to use for storing data. Also Known As - Chip-In-Card.
Suppression :
The addition of a device to an electrical circuit that minimizes or prevents transients from affecting the proper operation of that circuit.
Switch :
A device used to either connect or interrupt an electronic circuit.
