126 relations: A-law algorithm, Adaptive differential pulse-code modulation, AES3, Alec Reeves, Aliasing, Allies of World War II, Amplitude, Analog signal, Analog-to-digital converter, Anti-aliasing filter, Association for Recorded Sound Collections, Au file format, Audio bit depth, Audio Interchange File Format, AVCHD, Bartlane cable picture transmission system, Bell Labs, Bernard M. Oliver, Beta encoder, Bipolar encoding, Blu-ray, Cathode ray tube, Claude Shannon, Codec, Commutator (electric), Compact disc, Compact Disc Digital Audio, Companding, Data compression, Data stream, DATAR, Dbx (noise reduction), Delta modulation, Denon, Differential pulse-code modulation, Digital audio, Digital data, Digital filter, Digital signal (signal processing), Digital Signal 0, Digital signal processor, Digital-to-analog converter, Direct current, Douglas Whalen, DV, DVD, Dynamic range compression, Electric current, Emphasis (telecommunications), Equivalent pulse code modulation noise, ..., Fax, Ferranti-Packard, Floating-point arithmetic, Frame synchronization, Franklin S. Cooper, Frequency-division multiplexing, G.711, G.726, Gray code, Haskins Laboratories, HDMI, Hertz, Human voice, IEEE Communications Magazine, Institute of Electrical and Electronics Engineers, Integrated circuit, ITT Inc., Μ-law algorithm, James L. Flanagan, John R. Pierce, Library of Congress, Moses G. Farmer, Multiplexing, National Inventors Hall of Fame, NHK, Nibble, Nikil Jayant, No. 4 Electronic Switching System, Non-return-to-zero, Nyquist frequency, Nyquist–Shannon sampling theorem, Oscilloscope, Philip Rubin, Plate electrode, Polynomial, Pseudorandomness, Pulse-code modulation, Pulse-density modulation, Pulse-position modulation, Pulse-width modulation, Quantization (image processing), Quantization (signal processing), Raw audio format, Raw data, Return-to-zero, RF64, Run-length limited, S/PDIF, Sampling (signal processing), Scrambler, Signal compression, Signal-to-noise ratio, Signal-to-quantization-noise ratio, SIGSALY, Sine wave, Speech, Stereophonic sound, Stomu Yamashta, Stream (computing), Super Audio CD, T-carrier, Telecommunications Research Establishment, Telegraphy, Telephony, Time-division multiplexing, Tokyo, Uniform distribution (continuous), Video tape recorder, VOB, Voice over IP, Voltage, WAV, Western Electric, World War II, .m2ts, 44,100 Hz. Expand index (76 more) » « Shrink index
An A-law algorithm is a standard companding algorithm, used in European 8-bit PCM digital communications systems to optimize, i.e. modify, the dynamic range of an analog signal for digitizing.
Adaptive differential pulse-code modulation (ADPCM) is a variant of differential pulse-code modulation (DPCM) that varies the size of the quantization step, to allow further reduction of the required data bandwidth for a given signal-to-noise ratio.
AES3 (also known as AES/EBU) is a standard for the exchange of digital audio signals between professional audio devices.
Alec Harley Reeves (10 March 1902 – 13 October 1971) was a British scientist best known for his invention of pulse-code modulation (PCM).
In signal processing and related disciplines, aliasing is an effect that causes different signals to become indistinguishable (or aliases of one another) when sampled.
The Allies of World War II, called the United Nations from the 1 January 1942 declaration, were the countries that together opposed the Axis powers during the Second World War (1939–1945).
The amplitude of a periodic variable is a measure of its change over a single period (such as time or spatial period).
An analog signal is any continuous signal for which the time varying feature (variable) of the signal is a representation of some other time varying quantity, i.e., analogous to another time varying signal.
In electronics, an analog-to-digital converter (ADC, A/D, or A-to-D) is a system that converts an analog signal, such as a sound picked up by a microphone or light entering a digital camera, into a digital signal.
An anti-aliasing filter (AAF) is a filter used before a signal sampler to restrict the bandwidth of a signal to approximately or completely satisfy the sampling theorem over the band of interest.
The Association for Recorded Sound Collections (ARSC) is a nonprofit organization dedicated to the preservation and study of sound recordings.
The Au file format is a simple audio file format introduced by Sun Microsystems.
In digital audio using pulse-code modulation (PCM), bit depth is the number of bits of information in each sample, and it directly corresponds to the resolution of each sample.
Audio Interchange File Format (AIFF) is an audio file format standard used for storing sound data for personal computers and other electronic audio devices.
AVCHD (Advanced Video Coding High Definition) is a file-based format for the digital recording and playback of high-definition video.
Bartlane cable picture transmission system was a technique invented in 1920 to transmit digitized newspaper images over submarine cable lines between London and New York.
Nokia Bell Labs (formerly named AT&T Bell Laboratories, Bell Telephone Laboratories and Bell Labs) is an American research and scientific development company, owned by Finnish company Nokia.
Bernard M. Oliver (May 27, 1916 – November 23, 1995), also known as Barney Oliver, was a scientist who made contributions in many fields, including radar, television, and computers.
A beta encoder is an analog-to-digital conversion (A/D) system in which a real number in the unit interval is represented by a finite representation of a sequence in base beta, with beta being a real number between 1 and 2.
In telecommunication, bipolar encoding is a type of return-to-zero (RZ) line code, where two nonzero values are used, so that the three values are +, −, and zero.
Blu-ray or Blu-ray Disc (BD) is a digital optical disc data storage format.
The cathode ray tube (CRT) is a vacuum tube that contains one or more electron guns and a phosphorescent screen, and is used to display images.
Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American mathematician, electrical engineer, and cryptographer known as "the father of information theory".
A codec is a device or computer program for encoding or decoding a digital data stream or signal.
A commutator is a rotary electrical switch in certain types of electric motors and electrical generators that periodically reverses the current direction between the rotor and the external circuit.
Compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony and released in 1982.
Compact Disc Digital Audio (CDDA or CD-DA) is the standard format for audio compact discs.
In telecommunication and signal processing companding (occasionally called compansion) is a method of mitigating the detrimental effects of a channel with limited dynamic range.
In signal processing, data compression, source coding, or bit-rate reduction involves encoding information using fewer bits than the original representation.
In connection-oriented communication, a data stream is a sequence of digitally encoded coherent signals (packets of data or data packets) used to transmit or receive information that is in the process of being transmitted.
DATAR, short for Digital Automated Tracking and Resolving, was a pioneering computerized battlefield information system.
dbx is a family of noise reduction systems developed by the company of the same name.
A delta modulation (DM or Δ-modulation) is an analog-to-digital and digital-to-analog signal conversion technique used for transmission of voice information where quality is not of primary importance.
is a Japanese electronics company that was involved in the early stages of development of digital audio technology, while specializing in the manufacture of high-fidelity professional and consumer audio equipment.
Differential pulse-code modulation (DPCM) is a signal encoder that uses the baseline of pulse-code modulation (PCM) but adds some functionalities based on the prediction of the samples of the signal.
Digital audio is audio, or simply sound, signal that has been recorded as or converted into digital form, where the sound wave of the audio signal is encoded as numerical samples in continuous sequence, typically at CD audio quality which is 16 bit sample depth over 44.1 thousand samples per second.
Digital data, in information theory and information systems, is the discrete, discontinuous representation of information or works.
In signal processing, a digital filter is a system that performs mathematical operations on a sampled, discrete-time signal to reduce or enhance certain aspects of that signal.
In the context of digital signal processing (DSP), a digital signal is a discrete-time signal for which not only the time but also the amplitude has discrete values; in other words, its samples take on only values from a discrete set (a countable set that can be mapped one-to-one to a subset of integers).
Digital Signal 0 (DS0) is a basic digital signaling rate of 64 kilobits per second (kbit/s), corresponding to the capacity of one analog voice-frequency-equivalent communication channel.
A digital signal processor (DSP) is a specialized microprocessor (or a SIP block), with its architecture optimized for the operational needs of digital signal processing.
In electronics, a digital-to-analog converter (DAC, D/A, D2A, or D-to-A) is a system that converts a digital signal into an analog signal.
Direct current (DC) is the unidirectional flow of electric charge.
Douglas H. Whalen is an American linguist.
DV is a format for storing digital video.
DVD (an abbreviation of "digital video disc" or "digital versatile disc") is a digital optical disc storage format invented and developed by Philips and Sony in 1995.
Dynamic range compression (DRC) or simply compression is an audio signal processing operation that reduces the volume of loud sounds or amplifies quiet sounds thus reducing or compressing an audio signal's dynamic range.
An electric current is a flow of electric charge.
Typically, prior to some process, such as transmission over cable, or recording to phonograph record or tape, the input frequency range most susceptible to noise is boosted.
In telecommunication, equivalent pulse code modulation noise (PCM) is the amount of noise power on a frequency-division multiplexing (FDM) or wire communication channel necessary to approximate the same judgment of speech quality created by quantizing noise in a PCM channel.
Fax (short for facsimile), sometimes called telecopying or telefax (the latter short for telefacsimile), is the telephonic transmission of scanned printed material (both text and images), normally to a telephone number connected to a printer or other output device.
Ferranti-Packard Ltd. was the Canadian division of Ferranti's global manufacturing empire, formed by the 1958 merger of Ferranti Electric and Packard Electric.
In computing, floating-point arithmetic is arithmetic using formulaic representation of real numbers as an approximation so as to support a trade-off between range and precision.
In telecommunication, frame synchronization or framing is the process by which, while receiving a stream of framed data, incoming frame alignment signals (i.e., a distinctive bit sequences or syncwords) are identified (that is, distinguished from data bits), permitting the data bits within the frame to be extracted for decoding or retransmission.
Franklin Seaney Cooper (April 29, 1908 – February 20, 1999) was an American physicist and inventor who was a pioneer in speech research.
In telecommunications, frequency-division multiplexing (FDM) is a technique by which the total bandwidth available in a communication medium is divided into a series of non-overlapping frequency bands, each of which is used to carry a separate signal.
G.711 is an ITU-T standard for audio companding.
G.726 is an ITU-T ADPCM speech codec standard covering the transmission of voice at rates of 16, 24, 32, and 40 kbit/s.
The reflected binary code (RBC), also known just as reflected binary (RB) or Gray code after Frank Gray, is an ordering of the binary numeral system such that two successive values differ in only one bit (binary digit).
Haskins Laboratories is an independent 501(c) non-profit corporation, founded in 1935 and located in New Haven, Connecticut, since 1970.
HDMI (High-Definition Multimedia Interface) is a proprietary audio/video interface for transmitting uncompressed video data and compressed or uncompressed digital audio data from an HDMI-compliant source device, such as a display controller, to a compatible computer monitor, video projector, digital television, or digital audio device.
The hertz (symbol: Hz) is the derived unit of frequency in the International System of Units (SI) and is defined as one cycle per second.
The human voice consists of sound made by a human being using the vocal tract, such as talking, singing, laughing, crying, screaming, etc.
The IEEE Communications Magazine is a monthly magazine published by the IEEE Communications Society dealing with all areas of communications including light-wave telecommunications, high-speed data communications, personal communications systems (PCS), ISDN, and more.
The Institute of Electrical and Electronics Engineers (IEEE) is a professional association with its corporate office in New York City and its operations center in Piscataway, New Jersey.
An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small flat piece (or "chip") of semiconductor material, normally silicon.
ITT Inc., formerly ITT Corporation, is an American worldwide manufacturing company based in White Plains, New York.
The µ-law algorithm (sometimes written "mu-law", often approximated as "u-law") is a companding algorithm, primarily used in 8-bit PCM digital telecommunication systems in North America and Japan.
James Loton Flanagan (August 26, 1925 – August 25, 2015) was an electrical engineer, and was Rutgers University's vice president for research until 2004.
John Robinson Pierce (March 27, 1910 – April 2, 2002), was an American engineer and author.
The Library of Congress (LOC) is the research library that officially serves the United States Congress and is the de facto national library of the United States.
Moses Gerrish Farmer (February 9, 1820 – May 25, 1893) was an electrical engineer and inventor.
In telecommunications and computer networks, multiplexing (sometimes contracted to muxing) is a method by which multiple analog or digital signals are combined into one signal over a shared medium.
The National Inventors Hall of Fame (NIHF) is an American not-for-profit organization which recognizes individual engineers and inventors who hold a U.S. patent of highly significant technology.
is Japan's national public broadcasting organization.
In computing, a nibble (occasionally nybble or nyble to match the spelling of byte) is a four-bit aggregation, or half an octet.
Nikil Jayant (1945 --) is a prominent communications engineer who was a long-term researcher at Bell Laboratories and subsequently a professor at Georgia Institute of Technology.
In telecommunication, a non-return-to-zero (NRZ) line code is a binary code in which ones are represented by one significant condition, usually a positive voltage, while zeros are represented by some other significant condition, usually a negative voltage, with no other neutral or rest condition.
The Nyquist frequency, named after electronic engineer Harry Nyquist, is half of the sampling rate of a discrete signal processing system.
In the field of digital signal processing, the sampling theorem is a fundamental bridge between continuous-time signals (often called "analog signals") and discrete-time signals (often called "digital signals").
An oscilloscope, previously called an oscillograph, and informally known as a scope or o-scope, CRO (for cathode-ray oscilloscope), or DSO (for the more modern digital storage oscilloscope), is a type of electronic test instrument that allows observation of varying signal voltages, usually as a two-dimensional plot of one or more signals as a function of time.
Philip E. Rubin (born May 22, 1949, in Newark, New Jersey) is an American cognitive scientist, technologist, and science administrator.
A plate, usually called anode in Britain, is a type of electrode that forms part of a vacuum tube.
In mathematics, a polynomial is an expression consisting of variables (also called indeterminates) and coefficients, that involves only the operations of addition, subtraction, multiplication, and non-negative integer exponents of variables.
A pseudorandom process is a process that appears to be random but is not.
Pulse-code modulation (PCM) is a method used to digitally represent sampled analog signals.
Pulse-density modulation, or PDM, is a form of modulation used to represent an analog signal with a binary signal.
Pulse-position modulation (PPM) is a form of signal modulation in which M message bits are encoded by transmitting a single pulse in one of 2^M possible required time shifts.
Pulse-width modulation (PWM), or pulse-duration modulation (PDM), is a modulation technique used to encode a message into a pulsing signal.
Quantization, involved in image processing, is a lossy compression technique achieved by compressing a range of values to a single quantum value.
Quantization, in mathematics and digital signal processing, is the process of mapping input values from a large set (often a continuous set) to output values in a (countable) smaller set.
RAW Audio format or just RAW Audio is an audio file format for storing uncompressed audio in raw form.
Raw data, also known as primary data, is data (e.g., numbers, instrument readings, figures, etc.) collected from a source.
Return-to-zero (RZ or RTZ) describes a line code used in telecommunications signals in which the signal drops (returns) to zero between each pulse.
RF64 is a BWF-compatible multichannel file format enabling file sizes to exceed 4 GB.
Run-length limited or RLL coding is a line coding technique that is used to send arbitrary data over a communications channel with bandwidth limits.
S/PDIF (Sony/Philips Digital Interface) is a type of digital audio interconnect used in consumer audio equipment to output audio over reasonably short distances.
In signal processing, sampling is the reduction of a continuous-time signal to a discrete-time signal.
In telecommunications, a scrambler is a device that transposes or inverts signals or otherwise encodes a message at the sender's side to make the message unintelligible at a receiver not equipped with an appropriately set descrambling device.
Signal compression is the use of various techniques to increase the quality or quantity of signal parameters transmitted through a given telecommunications channel.
Signal-to-noise ratio (abbreviated SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise.
Signal-to-Quantization-Noise Ratio (SQNR or SNqR) is widely used quality measure in analysing digitizing schemes such as PCM (pulse code modulation) and multimedia codecs.
In cryptography, SIGSALY (also known as the X System, Project X, Ciphony I, and the Green Hornet) was a secure speech system used in World War II for the highest-level Allied communications.
A sine wave or sinusoid is a mathematical curve that describes a smooth periodic oscillation.
Speech is the vocalized form of communication used by humans and some animals, which is based upon the syntactic combination of items drawn from the lexicon.
Stereophonic sound or, more commonly, stereo, is a method of sound reproduction that creates an illusion of multi-directional audible perspective.
Stomu Yamashta (or Yamash'ta), born is a Japanese percussionist, keyboardist and composer.
In computer science, a stream is a sequence of data elements made available over time.
Super Audio CD (SACD) is a read-only optical disc for audio storage, introduced in 1999.
The T-carrier is a member of the series of carrier systems developed by AT&T Bell Laboratories for digital transmission of multiplexed telephone calls.
The Telecommunications Research Establishment (TRE) was the main United Kingdom research and development organization for radio navigation, radar, infra-red detection for heat seeking missiles, and related work for the Royal Air Force (RAF) during World War II and the years that followed.
Telegraphy (from Greek: τῆλε têle, "at a distance" and γράφειν gráphein, "to write") is the long-distance transmission of textual or symbolic (as opposed to verbal or audio) messages without the physical exchange of an object bearing the message.
Telephony is the field of technology involving the development, application, and deployment of telecommunication services for the purpose of electronic transmission of voice, fax, or data, between distant parties.
Time-division multiplexing (TDM) is a method of transmitting and receiving independent signals over a common signal path by means of synchronized switches at each end of the transmission line so that each signal appears on the line only a fraction of time in an alternating pattern.
, officially, is one of the 47 prefectures of Japan and has been the capital since 1869.
In probability theory and statistics, the continuous uniform distribution or rectangular distribution is a family of symmetric probability distributions such that for each member of the family, all intervals of the same length on the distribution's support are equally probable.
A video tape recorder (VTR) is a tape recorder designed to record and playback video and audio material on magnetic tape.
VOB (Video Object) is the container format in DVD-Video media.
Voice over Internet Protocol (also voice over IP, VoIP or IP telephony) is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet.
Voltage, electric potential difference, electric pressure or electric tension (formally denoted or, but more often simply as V or U, for instance in the context of Ohm's or Kirchhoff's circuit laws) is the difference in electric potential between two points.
Waveform Audio File Format (WAVE, or more commonly known as WAV due to its filename extension - both pronounced "wave") (rarely, Audio for Windows) is a Microsoft and IBM audio file format standard for storing an audio bitstream on PCs.
Western Electric Company (WE, WECo) was an American electrical engineering and manufacturing company that served as the primary supplier to AT&T from 1881 to 1996.
World War II (often abbreviated to WWII or WW2), also known as the Second World War, was a global war that lasted from 1939 to 1945, although conflicts reflecting the ideological clash between what would become the Allied and Axis blocs began earlier.
M2TS is a filename extension used for the Blu-ray Disc Audio-Video (BDAV) MPEG-2 Transport Stream (M2TS) container file format.
In digital audio, 44,100 Hz (alternately represented as 44.1 kHz) is a common sampling frequency.
Adapted Differential Pulse Code Modulation, Adaptive Differential PCM, LPCM, Linear PCM, Linear Pulse Code Modulation, Linear pcm, Linear pulse code modulation, Linear pulse-code modulation, Lpcm, PCM, PCM audio, PCM synthesis, Pcm, Pulse Code Modulation, Pulse code modulation, Pulse-code modulated.