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Audio Similarity
Computer audition (CA) or machine listening is the general field of study of algorithms and systems for audio interpretation by machines. Since the notion of what it means for a machine to "hear" is very broad and somewhat vague, computer audition attempts to bring together several disciplines that originally dealt with specific problems or had a concrete application in mind. The engineer Paris Smaragdis, interviewed in ''Technology Review'', talks about these systems "software that uses sound to locate people moving through rooms, monitor machinery for impending breakdowns, or activate traffic cameras to record accidents." Inspired by models of human audition, CA deals with questions of representation, transduction, grouping, use of musical knowledge and general sound semantics for the purpose of performing intelligent operations on audio and music signals by the computer. Technically this requires a combination of methods from the fields of signal processing, auditory modelli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algorithm
In mathematics and computer science, an algorithm () is a finite sequence of Rigour#Mathematics, mathematically rigorous instructions, typically used to solve a class of specific Computational problem, problems or to perform a computation. Algorithms are used as specifications for performing calculations and data processing. More advanced algorithms can use Conditional (computer programming), conditionals to divert the code execution through various routes (referred to as automated decision-making) and deduce valid inferences (referred to as automated reasoning). In contrast, a Heuristic (computer science), heuristic is an approach to solving problems without well-defined correct or optimal results.David A. Grossman, Ophir Frieder, ''Information Retrieval: Algorithms and Heuristics'', 2nd edition, 2004, For example, although social media recommender systems are commonly called "algorithms", they actually rely on heuristics as there is no truly "correct" recommendation. As an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Audio Texture
In music, texture is how the tempo and the melodic and harmonic materials are combined in a musical composition, determining the overall quality of the sound in a piece. The texture is often described in regard to the density, or thickness, and range, or width, between lowest and highest pitches, in relative terms as well as more specifically distinguished according to the number of voices, or parts, and the relationship between these voices (see Common types below). For example, a thick texture contains many 'layers' of instruments. One of these layers could be a string section or another brass. The thickness also is changed by the amount and the richness of the instruments playing the piece. The thickness varies from light to thick. A piece's texture may be changed by the number and character of parts playing at once, the timbre of the instruments or voices playing these parts and the harmony, tempo, and rhythms used. The types categorized by number and relationship of parts a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harmony
In music, harmony is the concept of combining different sounds in order to create new, distinct musical ideas. Theories of harmony seek to describe or explain the effects created by distinct pitches or tones coinciding with one another; harmonic objects such as chords, textures and tonalities are identified, defined, and categorized in the development of these theories. Harmony is broadly understood to involve both a "vertical" dimension (frequency-space) and a "horizontal" dimension (time-space), and often overlaps with related musical concepts such as melody, timbre, and form. A particular emphasis on harmony is one of the core concepts underlying the theory and practice of Western music. The study of harmony involves the juxtaposition of individual pitches to create chords, and in turn the juxtaposition of chords to create larger chord progressions. The principles of connection that govern these structures have been the subject of centuries worth of theoretical work ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhythm
Rhythm (from Greek , ''rhythmos'', "any regular recurring motion, symmetry") generally means a " movement marked by the regulated succession of strong and weak elements, or of opposite or different conditions". This general meaning of regular recurrence or pattern in time can apply to a wide variety of cyclical natural phenomena having a periodicity or frequency of anything from microseconds to several seconds (as with the riff in a rock music song); to several minutes or hours, or, at the most extreme, even over many years. The Oxford English Dictionary defines rhythm as ''"The measured flow of words or phrases in verse, forming various patterns of sound as determined by the relation of long and short or stressed and unstressed syllables in a metrical foot or line; an instance of this"''. Rhythm is related to and distinguished from pulse, meter, and beats: In the performance arts, rhythm is the timing of events on a human scale; of musical sounds and silences that occur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tonality
Tonality is the arrangement of pitch (music), pitches and / or chord (music), chords of a musical work in a hierarchy of perceived ''relations'', ''stabilities'', ''attractions'', and ''directionality''. In this hierarchy, the single pitch or the root (music), root of a triad (music), triad with the greatest ''stability'' in a melody or in its harmony is called the tonic (music), ''tonic''. In this context "stability" approximately means that a pitch occurs frequently in a melody – and usually is the final note – or that the pitch often appears in the harmony, even when it is not the pitch used in the melody. The ''root'' of the tonic triad forms the name given to the key (music), key, so in the key of C major, C major the note C can be both the tonic of the scale (music), scale and the root of the tonic triad. However, the tonic can be a different Musical tone, tone in the same scale, and then the work is said to be in one of the mode (music), ''modes'' of that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pitch Class
In music, a pitch class (p.c. or pc) is a set of all pitches that are a whole number of octaves apart; for example, the pitch class C consists of the Cs in all octaves. "The pitch class C stands for all possible Cs, in whatever octave position." Important to musical set theory, a pitch class is "all pitches related to each other by octave, enharmonic equivalence, or both." Thus, using scientific pitch notation, the pitch class "C" is the set : = . Although there is no formal upper or lower limit to this sequence, only a few of these pitches are audible to humans. Pitch class is important because human pitch-perception is periodic: pitches belonging to the same pitch class are perceived as having a similar quality or color, a property called " octave equivalence". Psychologists refer to the quality of a pitch as its "chroma". A ''chroma'' is an attribute of pitches (as opposed to ''tone height''), just like hue is an attribute of color. A ''pitch class'' is a set of all p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Envelope Detector
An envelope detector (sometimes called a peak detector) is an electronic circuit that takes a (relatively) high-frequency signal as input and outputs the '' envelope'' of the original signal. Diode detector A simple form of envelope detector used in detectors for early radios is the diode detector. Its output approximates a voltage-shifted version of the input's upper envelope. Between the circuit's input and output is a diode that performs half-wave rectification, allowing substantial current flow only when the input voltage is around a diode drop higher than the output terminal. The output is connected to a capacitor of value C and resistor of value R in parallel to ground. The capacitor is charged as the input voltage approaches its positive peaks. At other times, the capacitor is gradually discharged through the resistor. The resistor and capacitor form a 1st-order low pass filter, which attenuates higher frequencies at a rate of -6 dB per octave above its cu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pitch Detection Algorithm
A pitch detection algorithm (PDA) is an algorithm designed to estimate the pitch or fundamental frequency of a quasiperiodic or oscillating signal, usually a digital recording of speech or a musical note or tone. This can be done in the time domain, the frequency domain, or both. PDAs are used in various contexts (e.g. phonetics, music information retrieval, speech coding, musical performance systems) and so there may be different demands placed upon the algorithm. There is as yet no single ideal PDA, so a variety of algorithms exist, most falling broadly into the classes given below. A PDA typically estimates the period of a quasiperiodic signal, then inverts that value to give the frequency. General approaches One simple approach would be to measure the distance between zero crossing points of the signal (i.e. the zero-crossing rate). However, this does not work well with complicated waveforms which are composed of multiple sine waves with differing periods or noisy data. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feature Extraction
Feature may refer to: Computing * Feature recognition, could be a hole, pocket, or notch * Feature (computer vision), could be an edge, corner or blob * Feature (machine learning), in statistics: individual measurable properties of the phenomena being observed * Software feature, a distinguishing characteristic of a software program Science and analysis * Feature data, in geographic information systems, comprise information about an entity with a geographic location * Features, in audio signal processing, an aim to capture specific aspects of audio signals in a numeric way * Feature (archaeology), any dug, built, or dumped evidence of human activity Media * Feature film, a film with a running time long enough to be considered the principal or sole film to fill a program ** Feature length, the standardized length of such films * Feature story, a piece of non-fiction writing about news * Radio documentary (feature), a radio program devoted to covering a particular topic in so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Music
Computer music is the application of computing technology in music composition, to help human composers create new music or to have computers independently create music, such as with algorithmic composition programs. It includes the theory and application of new and existing computer software technologies and basic aspects of music, such as sound synthesis, digital signal processing, sound design, sonic diffusion, acoustics, electrical engineering, and psychoacoustics. The field of computer music can trace its roots back to the origins of electronic music, and the first experiments and innovations with electronic instruments at the turn of the 20th century. History Much of the work on computer music has drawn on the relationship between music and mathematics, a relationship that has been noted since the Ancient Greeks described the " harmony of the spheres". Musical melodies were first generated by the computer originally named the CSIR Mark 1 (later renamed CSIRAC) in Austra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Musicology
Musicology is the academic, research-based study of music, as opposed to musical composition or performance. Musicology research combines and intersects with many fields, including psychology, sociology, acoustics, neurology, natural sciences, formal sciences and computer science. Musicology is traditionally divided into three branches: music history, systematic musicology, and ethnomusicology. Historical musicologists study the history of musical traditions, the origins of works, and the biographies of composers. Ethnomusicologists draw from anthropology (particularly field research) to understand how and why people make music. Systematic musicology includes music theory, aesthetics, pedagogy, musical acoustics, the science and technology of musical instruments, and the musical implications of physiology, psychology, sociology, philosophy and computing. Cognitive musicology is the set of phenomena surrounding the cognitive modeling of music. When musicologists carry out ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auditory Scene Analysis
In perception and psychophysics, auditory scene analysis (ASA) is a proposed model for the basis of auditory perception. This is understood as the process by which the human auditory system organizes sound into perceptually meaningful elements. The term was coined by psychologist Albert Bregman. The related concept in machine perception is computational auditory scene analysis (CASA), which is closely related to source separation and blind signal separation. The three key aspects of Bregman's ASA model are: segmentation, integration, and segregation. Background Sound reaches the ear and the eardrum vibrates as a whole. This signal has to be analyzed (in some way). Bregman's ASA model proposes that sounds will either be heard as "integrated" (heard as a whole – much like harmony in music), or "segregated" into individual components (which leads to counterpoint). For example, a bell can be heard as a 'single' sound (integrated), or some people are able to hear the individual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
