Technical Glossary
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Displaying 84 glossary terms found.


Signal-To-Noise Ratio. The ratio, measured in decibels, between the audio or video signal level and that of the noise accompanying the signal. The higher the S/N ratio, the better the quality of the sound or picture.

Sony/Philips Digital Interface. The standard for digital data transmission between consumer audio components. Coaxial or optical (commonly Toslink) connections are used.

The process of dealing with something continuous in discrete sections.

Sampling Rate
The rate at which a signal is sampled, given in Hz. A sampling rate of 44.1 kHz, the standard for PCM audio, means that 44,100 samples are taken of the sound per second.

Second Audio Program. A separate mono audio signal that is broadcast along with the two stereo channels in the MTS system for stereo TV.

Satellite Speaker
A small stereo loudspeaker used in conjunction with a separate woofer.

The intensity and purity of the color signal, or the extent to which a given color in any image is free from white. The less white in a color, the truer the color, or the greater its saturation. On a display device, it can be adjusted with the color control. Not to be confused with the brightness, saturation is the amount of pigment in a color, and not the intensity. Low saturation is like adding white to the color. For example, a low-saturated red looks pink.

See Line Scaling Device.

1) In video, to move an electron beam across the raster in a camera or monitor. In NTSC video, each frame of the image is scanned from top to bottom as 525 stripes or lines. 2) To feed visual information into a computer by means of an optical device called a scanner. 3) Feature that scans programmed TV channels.

Scan Converter
Also called "video converter" or "TV converter", a scan converter is a device that changes the scan rate of a source video signal to fit the needs of a display device. Examples: computer-video to NTSC (TV), or NTSC to computer-video.

Scan Doubler
A device used to change composite interlaced video to non-interlaced component video, thereby increasing brightness and picture quality. Also called "line doubler."

Scan Rate
The frequency at which successive scans of a raster occur. In NTSC video the scan rate is 15,750 Hz.

Scan Velocity Modulation
SVM adjusts the rate of horizontal movement of the beam as it "draws" the scan lines on the screen. It distorts real picture detail in the process, causing dark areas of the picture on light backgrounds to be reproduced much larger than normal and light areas on dark backgrounds to be reproduced much smaller than normal. SVM is one of the many tricks manufacturers use to get more light out of a picture tube, again at the cost of the real picture detail. If SVM is found on a set, look for an ability to completely shut it OFF if high quality pictures are desired.

The process of making the scan lines less visible by doubling the number of lines and filling in the blank spaces. Also called "line-doubling."

The horizontal and vertical movement of the electron beam in a TV tube imaging device whereby each video frame is created.

Scanning Line
In imaging devices, electron beams scan the picture horizontally, line by line. The more scanning lines, the sharper, more finely detailed the picture.

Syundicat de Constructeurs d’ Appareils Radio Récepteur et Téléviseurs. Multi-pin A/V connector which carries composite video, data switching, RGB, Y/C and stereo audio signals. Named after Gallic committee that foisted the standard on Europe.

Scheimpflug Adjustment
A projector focus adjustment that changes the vertical angle of the lens, allowing perfect top-to-bottom focus when the projector is above or below the axis of the screen.

Serial Copy Management System. A copying limitation system for digital audio tape recorders that prevents succeeding generations of copies at the same quality level. Copies of copies can be made, but with each generational copy the signal-to-noise ratio drops further.

An original musical composition that accompanies the events seen on film. It is usually recorded with the movie playing to serve as the conductor’s guide.

Method of encoding cable TV signals to prevent theft of service. See Converter/Descrambler.

Screen Black
The light output at which a viewing screen is at its maximum darkness. This depends on ambient lighting as well as picture tube output.

Screen Gain
"Gain" is obtained by focusing energy in a particular direction. It is a measure of how much energy is available at a particular point compared to how much would be there if the source energy were dispersed equally in every direction. Screen gain is a measure of how much light is at the prime viewing position from the screen being tested versus how much light would be there if a flat matte reference screen material was being used as a screen. A screen would have a gain of 2 if twice as much light is available at the focus point of the screen as would be reflected by the reference. The reference for unity gain used by screen manufacturers is a matte white.

Screen Size
The diagonal measurement (or width, if specified), in inches, of the television screen.

Screen Surfaces
See Retro Reflective and Angular Reflective Screen Surfaces.

The displayed image (or interfering "noise" on the image) rolling constantly moving on the screen.

Small Computer System Interface - An industry-standard input/output bus for peripheral computer devices, such as hard disk and CD ROM drives. A standard peripheral bus on Mac computers.

Sony Dynamic Digital Sound. Sony’s theatrical multichannel digital sound format. SDDS is available in two configurations, SDDS-6, the 5.1 channel configuration, and SDDS-8 which adds two additional channels behind the screen. The proprietary ATRAC data compression/reduction system allows up to eight channels to be encoded in a single data bitstream and printed between the outer edge and the sprocket holes of the film. Two identical bitstreams line along both outer edges for backup purposes. The first film with SDDS was Last Action Hero in 1993.

Standard TeleVision. The Consumer Electronics Manufacturers Association (CEMA) standardized definition is a complete product/system with the following performance attributes:

A feature that permits faster-than-normal speed while playing a videocassette, LaserDisc, or DVD, usually in either direction and without sound. Used to locate a desired moment.

SEquential Couleur Avec Mémoire. Translated as "Sequential Color With Memory." A composite color transmission system that potentially eliminates a need for both a color and hue control on the monitor. One of the color difference signals is transmitted on one line and the second is transmitted on the second line. Memory is required to obtain both color difference signals for color decoding. This system is used in France, Africa, Asia, Russia, Saudi Arabia and many Eastern European countries Similar to PAL, but produces color signals in a different manner. 625 horizontal scan lines, 50 fields per second (625/50).

Second Audio Program

Special Effects Generator. A video mixing device that allows switching among several cameras and a variety of special e ffects such as dissolves, fades, wipes and inserts.

1) The amount of input signal that a transducer requires in order to produce a specified amount of output. 2) The amount of output signal delivered by a transducer when fed a specified amount of input signal.

A theatrical sound system from Cerwin-Vega in the 1970s to enhance the visceral realism of low frequency effects. The soundtrack would contain specific cues whereby low frequency pink noise would be played through several woofers located throughout the auditorium. Sensurround was used for four films—Earthquake, Rollercoaster, Battlestar Galactica and Midway.

The degree to which a stereo system can separate the left and right channels to produce a proper stereo image.

Sequential Scan
A video imaging technique in which the entire frame is drawn in a single top-to-bottom scan. Line doublers produce a sequential or progressive scan image. See Non-Interlaced.

Serial Copy Management System

Serial Data
A way to transfer information by breaking the characters of a word into bits which are then transmitted sequentially along a single line. Compare to parallel, which uses more than one line.

Serial Port
An input/output connection on the computer that allows it to communicate with other devices in a serial fashion – data bits flowing on a single pair of wires. The serial port is used with RS-232 protocol.

Series Resistance
Any cable system requires energy to move electrons through a material, and all materials have an inherent force that tries to prevent the electrons from passing through that material. This is called series resistance. The amount of series resistance in a wire is affected by the diameter and length of the center conductor. Resistance increases as length increases or as size decreases. Likewise, resistance decreases as size increases or length decreases. In other words, a short, fat cable has less resistance than a long, skinny one. Excessive resistance in a cable will attenuate the signal. If the video signal goes through a lot of devices before reaching the display, it can be destroyed by a lot of little cables. A good cable should have as little resistance as possible.

Shadow Mask
A metal plate behind the face plate of a picture tube with perforated holes or vertical lines that is used to determine exactly where the electron beam strikes the CRT screen, directing each of the electron guns exclusively to its own phosphor dots. See Invar.

The definition of the edges or apparent focus of a video image. See Peaking.

Sharpness Control
Adjusts the amount of detail enhancement or high frequency peaking to be added to the black and white portion of the video signal. A Sharpness control can cause trouble with better quality video sources. Adding frequency peaking in the middle of the luminance bandwidth, as is done with the Sharpness control, is asking for trouble. In sets with comb filter decoders, increasing the Sharpness control will add extra edges to at least some of the transitions in the medium gray to black picture transitions, making them stand out. The extra white areas will appear on either side of the black lines. The problem with this is that by turning up the Sharpness control to the point of these extra lines being visible, information is added to the picture that is not part of the original signal. In addition, noise is added when increasing the Sharpness control. While this added noise may give the impression of more detail, it has little or nothing to do with the original signal or any real picture detail. In both cases, turning up the Sharpness control adds false information to the picture. The correct position of the Sharpness control is just below the point where extra lines are being added to the picture. In most consumer sets, the correct position is at the lowest possible setting. Same as Peaking Control.

In audio/video and home theatre systems, loudspeakers may be magnetically treated, or shielded, to prevent their magnets from discoloring the picture on an adjacent display device. More generally, shielding refers to any effort to prevent magnetic radiation in one component from affecting another.

Shifting Center
An apparent shift of the position of an instrument or voice in the stereo image due to a discrepancy in the phase relationships of the signals from either side.

Showcase Print
The highest quality theatrical print that is dubbed in real time on premium film stock, rather than regular high speed printing on mediocre film stock. Showcase prints are limited in number and reserved for high profile movies and directors.

Characterized by, or producing a hissing sound like that of "S," "SH" or "CH."

The series of continually changing electrical voltages or impulses that correspond to variations in the brightness or loudness of the original scene or sound.

Signal-To-Noise Ratio
S/N. The ratio of signal (electrical impulses carrying information) to noise (impurities in signal). The difference between the nominal or maximum peak-to-peak voltage operating level and the voltage of the noise floor expressed in dB. The higher the video S/N, the clearer the picture; the higher the audio S/N the quieter the absence of sound. See S/N.

Sine Wave
A waveform whose instantaneous value follows the trigonometric sine function. A sine wave depicts the variation of amplitude with time of a pure tone (such as that produced by a tuning fork). A sine wave is the purest waveform possible, having no harmonic content.

Single System
The playback of sound and picture from the same medium. The obvious example is optical soundtracks; they are printed on the film alongside the image.

See Tilt.

Slap Back
A discrete reflection from a nearby surface.

Slap Back
A discrete reflection from a nearby surface.

Slit Mask
Type of shadow mask using vertical slits instead of round perforations.

Society of Motion Picture and Television Engineers. A global organization, based in the United States, that sets standards for baseband visual communications. This includes film as well as video standards.

SMPTE Color Bars
SMPTE Color Bars are used for adjusting the Color and Tint controls. See SMPTE Pattern.

SMPTE Pattern
The video test pattern consisting of color, black and white bands used as a standard for setting up video equipment. The color bars pattern allows accurate calibration of a monitor’s saturation and hue settings by means of a blue filter.

SMPTE Resolution Chart
A test pattern to measure horizontal and vertical resolution and picture area to determine overscan. See Overscan.

Visual "noise" or interference in a video picture giving the appearance of white specks or flakes of snow.

Society Of Motion Picture And Television Engineers
SMPTE. An international organization dedicated to advancements and standards in the field of motion-imaging technology, such as film and video. See SMPTE.

1) In video, deficient in sharpness and detail; out of focus. 2) In audio, deficient in treble response; slightly dull.

The programs used to instruct a processor and its peripheral equipment to perform prescribed operations.

Solid State
Commonly used to indicate use of semiconductor devices in place of tubes.

Sonic Feedback
Sound distortion resulting from the return of a portion of the output of a circuit or device to its input.

Having or producing a full, deep, or rich sound.

The phenomenon caused by the vibration of the eardrum. The drum itself is set into motion by pressure waves traveling through the air, originating at the sound source.

Sound Designer
A person who artistically crafts various sound effects to provide an aural accompaniment to the events on screen, i.e., special effects and Foley and soundscapes.

Sound Effect Library
A collection of recorded sound effects.

Sound Level Meter
A pressure-sensitive device which measures loudness. Sound level meters have several scales corresponding to the sensitivities of the human ear at different frequencies.

Sound Pressure Level
SPL. The standard measurement of the loudness of a sound, expressed in decibels (dB) relative to the threshold of human hearing. See SPL.

Sound Transmission
1) Airborne. The conduction of a sound wave through air. The speed of airborne sound transmission varies with temperature and humidity, and is 1130 feet/second in air at 70 F. 2) Structure Borne. The conducting of a sound wave through a physical structure (such as a wall, floor, ceiling or door). Because of the increased speeds of sound through common building materials (wood @ 11,700 feet/second, steel @ 18,000 feet/second) as well as the physical connection of such materials in the structural framework of a building, structure borne sound transmission is much more difficult to stop than airborne sound transmission, and thus requires special measures to be dealt with effectively.

The recording of film sound onto a phonograph record, as used in the late 1920’s. The technology became difficult to rely on because of problems synchronizing the sound with the moving image.

The recording of movie sound onto a film print, either alongside the image (single system) or on a medium separate from the picture (double system).

The impression of a three-dimensional holosonic spatial experience. See Holosonic.

A device, mounted on the projector which reads the sound information from the film. The area correlating with the projected image frame is illuminated using an exciter lamp (or LED for digital sound) and detected by either an photoelectric cell or CCD camera, depending on whether analog (optical) or digital (Dolby Digital, SDDS) information is being read. For a magnetic soundtrack an electromagnetic head picks up the audio signal.

A room or studio that is usually soundproof, used for the production of movies. Or, the psycho acoustic phenomena where a two-dimensional image (left-to-right and front-to-back) is created in the mind suggesting the physical relationship of the listener to the individual performers. A well designed listening space will create the impression of a much larger sound stage spread and depth than the physical placement of the speakers or the size of the room could allow.

Soundstage Depth
The impression of instruments, voices or sounds existing behind one another in three dimensions.

A term of relevance to movie sound but with several meanings: 1) the musical content of a film, 2) all of a movie’s sonic attributes —sound effects, Foley, music, dialogue, and 3) the actual location of the sound information on film.

Spatial Resolution
Spatial resolution is a measurement of the total number of pixels displayed in an entire image, usually noted in terms of horizontal by vertical (640 x 480).

Spatially Integrated
A descriptive term that describes the characteristic of dialogue, usually looped or ADR-produced, that is either spatially integrated or not with the scene or scenes in a movie. The term also is used when describing Foley and sound effects spatial integration.

Loudspeaker. May refer to a single driver or the entire speaker system.

Standard Remote
Is an enhanced basic model with a keypad for direct access plus allowing you to use on-screen menus and displays.