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Safe Title Area.
Generally, the center 80% of the entire overscan video image area or that area which will display legible titles regardless of how a TV monitor is adjusted.

Sampler.
An electronic device that can record, alter and playback digital audio data under the control of a MIDI data stream.

Sampling.
Digitizing a waveform by measuring its amplitude fluctuations at some precisely timed intervals. The accuracy of the measurements is a function of the bit resolution.

Sampling frequency.
The number of measurements made per period of time (i.e., per second).

Sampling Rate.

Number of samples or snapshots taken of a particular signal in a given amount of time (usually one second).

The rate at which samples of a waveform are made. Must be twice the highest frequency one wishes to capture. Commercial compact discs use a rate of 44,100 samples per second.

Satellite Speaker.
A small- to medium-size speaker usually 12 to 24 inches in height designed to be placed on stands or other objects and operated with a subwoofer.

Saturation.
Refers to the depth or intensity of a colour on a video display based on how much white is present in proportion to the pure colour creating, for example, a deep red having a high level of saturation (mostly pure red with little white) or pinkish red being lightly saturated (less pure red and a higher level of white); the amount of pure colour present in an image or portion of an image.

Scan Line.
A single horizontal line on a video display which, when combined with other lines on the screen, creates a complete image.

Scan Rate.
Speed at which a video display device paints lines onto a screen.

Scan Velocity Modulation.
Technique employed on some cathode ray tube television sets for slowing down or speeding up the electron gun as it scans or paints each horizontal line of information.

SCART.
An audio/video connector used in consumer equipment, especially in Europe. The SCART connector's 21 pins carry two audio in and out channels, in and out video channels, RGB signals, ground and some additional control signals. Only one SCART-to-SCART cable is needed to connect two VCRs or VCR to a monitor thereby avoiding the need for multiple cables.

Screen Trigger.
Low-voltage signal sent from a video projector to a motorized screen causing the screen to lower or roll up.

SCSI (Small Computer Systems Interface).
A hard disk drive controller. Variations include SCSI-2, SCSI-wide, and SCSI-Ultrawide for faster speeds.

SDDS (Sony Dynamic Digital Sound).
Digital surround sound audio format developed by Sony for exclusive use in commercial theater installations.

SDTV (Standard Definition Television).
Twelve standard quality forms of the digital television standard adopted for the United States featuring AC-3 digital surround sound, wide (16:9) and "square" (4:3) aspect ratios and high-quality (though not high definition) digital video capable of interlaced and progressive scan images with 480 horizontal lines (vertical resolution) by 704 vertical lines (horizontal resolution) at 24, 30 and 60 Hz refresh rates and video capable of interlaced and progressive scan images with 480 horizontal lines by 640 vertical lines at 24, 30 and 60 Hz refresh rates.

SDRAM (Synchronous DRAM).
A DRAM varient with improved access time.

SECAM.
SEquential Colour And Memory Television broadcast format developed in France and used in France, Russia and a variety of other countries featuring 625 horizontal lines of resolution. incompatible with our NTSC system.

Seek Time.
Time it takes a disk drive to find data and begin sending it out.

Segue (pronounced "SEG-way").
A smooth change from one sound, place, or subject to another.

Selectivity.
Ability of a tuner to receive stations spaced close together on the radio frequency spectrum without the channels interfering with one another.

Serial.
A way of sending computer data over a single wire, one command after another. Long wires are possible. Modems and mice are serial devices, as are RS-422 and RS 232 ports on a computer.

Serial Port.
A computer l/O (input/output) port through which the computer communicates with the external world. The standard serial port uses RS-232 or RS-422* protocols.

Servo.
Specially designed electronic circuit loop which measures speaker distortion and works with the speaker's amplifier to correct the signal in an effort to decrease distortion.

Servo Lock.
Editing VCR feature that assures vertical interval edits only at the end of even (or odd) fields.

Session.
An event on a CD. A single session might be a series of songs on a CD or a file on a CD-ROM. CD players are capable of playing single sessions only and CDs have a single session on them.

Sequencer.
MIDI software or less commonly, a hardware device that can record, edit and playback a sequence of MIDI data.

Signal.
The form of variation with time of a wave whereby information is conveyed in some form whether it is acoustic or electronic.

Signal to noise ratio (S/N).
The ratio in decibels (dB), of an audio or video signal, between the signal's maximum peak-to-peak signal voltage and the measured voltage of what remains when the signal is removed, (i.e., the ratio of the signal to that of the noise). In video, the higher the ratio, the less snow is visible. In audio, the higher the ratio, the cleaner the sound. Audio s/n ratios vary tremendously from compact discs/camcorder AFM Hi-Fi tracks (typically 90 dB) to VCR linear tracks (typically 40 dB).

Sine Wave.

Type of pure waveform having an equal distance from its peak to the zero or center line and from its trough to the center line and in which the positive hump and negative hump of the wave are exactly equal in length, shape and height but flipped in a mirror image about the center line.

The most basic waveform, consisting of a single partial. Forms the basis of all complex, periodic sounds.

Skew.
Distortion of an image on a video display resulting in lines that are supposed to be horizontal or vertical appearing to tilt or lean from their proper horizontal or vertical orientations.

Slew Rate.
Fastest rate at which an amplifier can change the amplitude of its output signal measured in volts per microsecond with a higher figure being better (meaning that the amplifier can change more voltage in a given period of time, one microsecond).

Slope.
How quickly a crossover or filter attenuates signals (decreases their power) outside its passband (those frequencies intended to pass through without attenuation); expressed in decibels per octave.

Smear.
A temporary white vertical streak passing through bright objects in a CCD camera's picture.

Smoothshade.
Rounded surface applied to what the computer calculates to be round surfaces to give wireframes substance and realism. Smoothshades render quickly but not as quickly as flatshades.

SMPTE Time Code.
1.) A time code used to address every frame on a tape with a unique number to aid in logging and editing. The time code format is standardized in the United States by the Society of Motion Picture and Television Engineers.
2.) A timing standard adopted by the Society of Motion Picture and Television Engineers for controlling different audio and video devices. Allows a sequencer and an external device such as a tape recorded to stay synchronized.

Snow.
A general term used to describe interference in a video image. It manifests as random coloured or black and white dots.

Solarization.
Special effect in which the lightest and darkest values of a picture are made dark while the middle tones become light.

Solid State.
Electronic component composed of transistors and integrated circuits using no vacuum tubes.

Sound Card.
Circuit installed in a computer to change audio signals into data the computer can handle and vice versa.

Sound Colouration.
The characteristic tone a microphone gives to the sounds it picks up.

Sound Mix.
The process of editing and mixing numerous sounds into the final form heard by the audience.

Sound Pressure Level.
Measurement in decibels of the pressure or force exerted by a sound wave on the environment with increasing pressure generating increased loudness or higher volume (creating more pressure in the ear increases perceived loudness).

Soundstage.
The perceived width, depth and height of recorded sound played back over an audio system; the setting similar to a theater stage from which sounds seem to emanate when reproduced through an audio system Sound Wave Continuous audio frequency signal taking the form of a wavy line similar to waves on the water with frequency determining the length of the waves and amplitude or volume determining the height of the waves.

Source Encoding.
Refers to techniques in which the characteristics of the original signal source are exploited to allow more compression.
Source encoding falls into three broad categories

Transform Encoding,

Differential Encoding

Vector Quantisation

Speech Analysis

In acoustic analysis, the principle is applied to sound patterns - phones, allophones, syllables and words

In syntactical analysis, the grammatical arrangement of the speech units is analysed. This allows errors in the acoustic analysis to be recognised and possibly corrected. The result is recognised speech.

In semantic analysis, the meaning of the recognised speech is analysed. Again, errors can be recognised and possibly corrected with other analysis methods. The result of this step is understood speech.

Speech Recognition.

The purposes of speech recognition can be divided into three areas.

Who? - Verification and/or identification of the speaker

What? - Recognition and/or understanding of the spoken words

Why? - Determination of the reasons why particular words are spoken

Special Effects Generator (SEG).
Electronic video device that creates effects such as wipes, fades, keys, etc.

Speaker.
Mechanical device used to reproduce sound waves when a power signal is applied representing those sound waves by vibrating some material that in turn creates vibrations in the air thus generating sound.

Special Effects.
Artistic effects added to a video production in order to enhance the production by creating drama, enhancing the mood or furthering the story. Special effects may vary from the limited addition of patterns or the mixing of several video images together, to sophisticated digital effects such as picture compression, page flipping and three-dimensional effects. Special effects are usually created using SEGs.

Spectrum.
A band or range of frequencies; the audible spectrum runs from 20 Hz to 20,000 Hz (20 kHz).

Specular Colour.
The highlight you get on shiny surfaces.

SPID (Service Profile Identifier).
A number telling the phone company what kind of device (phone, fax, computer) you have connected to an ISDN line.

SPL Meter.
Device that measures the sound pressure level in a given location; commonly used in audio to properly set surround sound systems to the Dolby reference level and adjust other parameters of a sound system.

Split screen.
An electronic process which allows the viewing of two video images, side by side or above and below, on-screen simultaneously.

SQL
Structured Query Language. (Database).

Standards Converter.
A device that changes one standard of video signal (say, NTSC) into another (say, PAL) or vice versa, bridging the gap of incompatibility between standards.

Standard Midi File.
A standardized form of data used for exchanging MIDI files between programs.

Standing Wave.
Low frequency anomaly or distortion created when a certain frequency is reproduced whose size has some special relation to the room or object it is produced in (wavelength the same size as the room dimensions) resulting in the room or object resonating with the sound and increasing the strength of the sound (the sound wave does not diminish and may instead increase as it interacts with its surroundings).

Star Pattern.
Lens effect creating shafts of light gleaming from any bright points of light in a picture.

Status Byte.
The first byte of a MIDI message that specifies what type of message it is.

Step Time.
Entering notes one by one, as opposed to real time recording in a sequencer.

Stereo.
Two channels of audio information recorded and played back in such a way as to recreate a sound stage giving depth and breadth to audio reproduction.

Stereo Imaging.
Ability to discern the original positions or placement of sounds when listening to earphones or speakers.

Stereo Separation.
The amount of difference there is between the left and right stereo channels. Poor separation mixes the two together. No separation is monaural sound.

Stereo Mixing.
Simultaneous processing of both left and right audio channels.

Streaking.
This is where colours continue into another, it occurs where intensity changes abruptly.

Stop Edit.
Technique of editing a video tape by stopping the VCR (pressing stop) at the end of one scene and then starting it recording again (pressing record/play) at the beginning of the next.

Storyboard.
A script done in pictures, showing the sequence of shots that will make the show. NLEs allow you to make a storyboard from the picons captured from tape.

Strobe.
Special effect in which a frame is periodically held for a finite time until another frame is held.

Subtractive Primary.
The three primary colours (magenta, cyan and yellow) used to absorb or subtract parts of the complete spectrum of white light to form the complete colour spectrum; colours that absorb all other wavelengths of light but their own reflecting back only their own colour wavelength of light.

Super.
SVHS, Hi8, ED Beta 3/4U-SP or any improvement to a VCR format that increases the picture sharpness above 400 lines of resolution. Sometimes called High Band.

Superimpose.
To place in front of video, e.g., placing text over a video signal.

Surround (Speaker Driver Surround).
Flexible rubber, plastic, foam or other material that attaches a speaker driver's diaphragm (the moving cone or dome - the drive unit) to the basket (the structure holding all the parts of the speaker driver in place) and allows the diaphragm to vibrate in and out.

Suspension.
The flexible element of a speaker driver that attaches the moving diaphragm to the basket and holds the diaphragm in proper relation to the rest of the speaker driver components and helping to enable the diaphragm to move and produce sound.

Sustain Pedal.
A pedal on a MIDI controller (or acoustic piano) that keeps all notes sounding even a key is released.

Surface Tessellation.
The process by which geometrical objects are converted to facets.

S-VHS-C (Super VHS-C).
An improved version of the VHS-C tape format capable of recording better picture resolution.

S-Video (Separated Video).
Describes a system of plugs and jacks used to interconnect camcorders, VCRs and TV monitors, which keeps the chrominance (colour) and luminance (brightness) information separate. Also called Y/C connectors (luminance/chrominance), this system greatly improves picture quality by keeping any signal interaction (degradation) to a minimum.

SYNC (Synchronization).
A term used in electronics to describe the precise alignment of two signals or functions. In video, sync is an essential element for maintaining the proper clocking of video signals. The sync signal is used by a monitor to know where and when to draw the on-screen video image. The horizontal sync signal is a short pulse generated at the beginning of each video line which tells the video monitor when to draw each new line. The vertical sync signal is a short pulse generated at the beginning of each video frame which tells the video monitor when to start a new field.

Synthesizer.
Musical device that makes sounds electronically.

System Common Messages.
MIDI messages used for various functions including tuning an instrument and song selection.

System Exclusive Message.
MIDI message used to communicate with a device made by a specific manufacturer.

System Real Time Messages.
Commands used to synchronize one MIDI device with another.

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