Speech recognitionSpeech recognition is an interdisciplinary subfield of computer science and computational linguistics that develops methodologies and technologies that enable the recognition and translation of spoken language into text by computers. It is also known as automatic speech recognition (ASR), computer speech recognition or speech to text (STT). It incorporates knowledge and research in the computer science, linguistics and computer engineering fields. The reverse process is speech synthesis.
SyllableA syllable is a unit of organization for a sequence of speech sounds typically made up of a syllable nucleus (most often a vowel) with optional initial and final margins (typically, consonants). Syllables are often considered the phonological "building blocks" of words. They can influence the rhythm of a language, its prosody, its poetic metre and its stress patterns. Speech can usually be divided up into a whole number of syllables: for example, the word ignite is made of two syllables: ig and nite.
Syllable weightIn linguistics, syllable weight is the concept that syllables pattern together according to the number and/or duration of segments in the rime. In classical Indo-European verse, as developed in Greek, Sanskrit, and Latin, distinctions of syllable weight were fundamental to the meter of the line. Mora (linguistics) A heavy syllable is a syllable with a branching nucleus or a branching rime, although not all such syllables are heavy in every language.
International Phonetic AlphabetThe International Phonetic Alphabet (IPA) is an alphabetic system of phonetic notation based primarily on the Latin script. It was devised by the International Phonetic Association in the late 19th century as a standardized representation of speech sounds in written form. The IPA is used by lexicographers, foreign language students and teachers, linguists, speech–language pathologists, singers, actors, constructed language creators, and translators.
Length (phonetics)In phonetics, length or quantity is a feature of sounds that have distinctively extended duration compared with other sounds. There are long vowels as well as long consonants (the latter are often called geminates). Many languages do not have distinctive length. Among the languages that have distinctive length, there are only a few that have both distinctive vowel length and distinctive consonant length. It is more common that there is only one or that they depend on each other.
Mora (linguistics)A mora (plural morae or moras; often symbolized μ) is a basic timing unit in the phonology of some spoken languages, equal to or shorter than a syllable. For example, a short syllable such as ba consists of one mora (monomoraic), while a long syllable such as baa consists of two (bimoraic); extra-long syllables with three moras (trimoraic) are relatively rare. Such metrics are also referred to as syllable weight. The term comes from the Latin word for 'linger, delay', which was also used to translate the Greek word χρόνος : chrónos ('time') in its metrical sense.
PhonotacticsPhonotactics (from Ancient Greek phōnḗ "voice, sound" and taktikós "having to do with arranging") is a branch of phonology that deals with restrictions in a language on the permissible combinations of phonemes. Phonotactics defines permissible syllable structure, consonant clusters and vowel sequences by means of phonotactic constraints. Phonotactic constraints are highly language-specific. For example, in Japanese, consonant clusters like /st/ do not occur.
TelephoneA telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals that are transmitted via cables and other communication channels to another telephone which reproduces the sound to the receiving user. The term is derived from τῆλε (tēle, far) and φωνή (phōnē, voice), together meaning distant voice.
PhoneticsPhonetics is a branch of linguistics that studies how humans produce and perceive sounds, or in the case of sign languages, the equivalent aspects of sign. Linguists who specialize in studying the physical properties of speech are phoneticians. The field of phonetics is traditionally divided into three sub-disciplines based on the research questions involved such as how humans plan and execute movements to produce speech (articulatory phonetics), how various movements affect the properties of the resulting sound (acoustic phonetics), or how humans convert sound waves to linguistic information (auditory phonetics).
Acoustic modelAn acoustic model is used in automatic speech recognition to represent the relationship between an audio signal and the phonemes or other linguistic units that make up speech. The model is learned from a set of audio recordings and their corresponding transcripts. It is created by taking audio recordings of speech, and their text transcriptions, and using software to create statistical representations of the sounds that make up each word. Modern speech recognition systems use both an acoustic model and a language model to represent the statistical properties of speech.
Phonemic orthographyA phonemic orthography is an orthography (system for writing a language) in which the graphemes (written symbols) correspond to the phonemes (significant spoken sounds) of the language. Natural languages rarely have perfectly phonemic orthographies; a high degree of grapheme–phoneme correspondence can be expected in orthographies based on alphabetic writing systems, but they differ in how complete this correspondence is.
Single-sideband modulationIn radio communications, single-sideband modulation (SSB) or single-sideband suppressed-carrier modulation (SSB-SC) is a type of modulation used to transmit information, such as an audio signal, by radio waves. A refinement of amplitude modulation, it uses transmitter power and bandwidth more efficiently. Amplitude modulation produces an output signal the bandwidth of which is twice the maximum frequency of the original baseband signal.
ConsonantIn articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract. Examples are [p] and [b], pronounced with the lips; [t] and [d], pronounced with the front of the tongue; [k] and [g], pronounced with the back of the tongue; [h], pronounced in the throat; [f], [v], and [s], pronounced by forcing air through a narrow channel (fricatives); and [m] and [n], which have air flowing through the nose (nasals). Contrasting with consonants are vowels.
Speech processingSpeech processing is the study of speech signals and the processing methods of signals. The signals are usually processed in a digital representation, so speech processing can be regarded as a special case of digital signal processing, applied to speech signals. Aspects of speech processing includes the acquisition, manipulation, storage, transfer and output of speech signals. Different speech processing tasks include speech recognition, speech synthesis, speaker diarization, speech enhancement, speaker recognition, etc.
Telephone keypadA telephone keypad is a keypad installed on a push-button telephone or similar telecommunication device for dialing a telephone number. It was standardized when the dual-tone multi-frequency signaling (DTMF) system was developed in the Bell System in the United States in the 1960s that replaced rotary dialing originally developed in electromechanical switching systems. Because of the installed abundance of rotary dial equipment well into the 1990s, many telephone keypads were also designed to produce loop-disconnect pulses electronically, and some could be optionally switched to produce either DTMF or pulses.
History of the telephoneThis history of the telephone chronicles the development of the electrical telephone, and includes a brief overview of its predecessors. The first telephone patent was granted to Alexander Graham Bell in 1876. Before the invention of electromagnetic telephones, mechanical acoustic devices existed for transmitting speech and music over a greater distance. This distance was greater than that of normal direct speech. The earliest mechanical telephones were based on sound transmission through pipes or other physical media.
Speech perceptionSpeech perception is the process by which the sounds of language are heard, interpreted, and understood. The study of speech perception is closely linked to the fields of phonology and phonetics in linguistics and cognitive psychology and perception in psychology. Research in speech perception seeks to understand how human listeners recognize speech sounds and use this information to understand spoken language.
Feature selectionFeature selection is the process of selecting a subset of relevant features (variables, predictors) for use in model construction. Stylometry and DNA microarray analysis are two cases where feature selection is used. It should be distinguished from feature extraction. Feature selection techniques are used for several reasons: simplification of models to make them easier to interpret by researchers/users, shorter training times, to avoid the curse of dimensionality, improve data's compatibility with a learning model class, encode inherent symmetries present in the input space.
Neural machine translationNeural machine translation (NMT) is an approach to machine translation that uses an artificial neural network to predict the likelihood of a sequence of words, typically modeling entire sentences in a single integrated model. They require only a fraction of the memory needed by traditional statistical machine translation (SMT) models. Furthermore, unlike conventional translation systems, all parts of the neural translation model are trained jointly (end-to-end) to maximize the translation performance.
Orthogonal frequency-division multiplexingIn telecommunications, orthogonal frequency-division multiplexing (OFDM) is a type of digital transmission used in digital modulation for encoding digital (binary) data on multiple carrier frequencies. OFDM has developed into a popular scheme for wideband digital communication, used in applications such as digital television and audio broadcasting, DSL internet access, wireless networks, power line networks, and 4G/5G mobile communications. OFDM is a frequency-division multiplexing (FDM) scheme that was introduced by Robert W.
