DOCSLIB.ORG

Granular Synthesis Is a Synthesis Method That Operates on the Microsonic Time Scale

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Granular Synthesis Is a Synthesis Method That Operates on the Microsonic Time Scale Jean-Luc Sinclair • Granular synthesis is a synthesis method that operates on the microsonic time scale. • It was first articulated in a paper written in 1946 by Dennis Gabor, in which he describes a synthesis method modeled on quantum physics ideas. The concept of Gabor Atoms was born. • Sound Quanta: indivisible unit of sound • Time is reversible at the quantum level. A granular sound will sound the same whether the grains are played forward or backward. This property allows for time stretching and pitch shifting applications of granular synthesis. “The grain is an apt representation of sound because it combines time domain information (starting time, envelope shape, duration) with frequency domain information (period of the waveform inside grain, spectrum of the waveform). This stands in opposition to representation at the sample level that do not capture frequency-domain information and abstract Fourier methods that presume that sounds are summation of infintely long sine waves” Curtis Roads. • It wasn’t until 1971 and Iannis Xenakis that this technique was used for audio synthesis. • A high density of small audio events, called grains and usually less than 50ms in duration are generated creating granular clouds and streams. • The typical duration of a grain is 10 to 30ms • Typical densities range from a few dozens to several thousand grain per seconds • The grains may come from a wavetable, another synthesis technique or sampled sounds Curtis Roads organizes granular synthesis techniques into five categories: • Quasi-synchronous granular synthesis • Asynchronous granular synthesis • Pitch-synchronous granular synthesis • Granulation of concrete (sampled) sounds • Fourier and wavelet grids • Quasi-synchronous granular synthesis: one or more streams are generated each keeping the interval between grains equally spaced. The overall envelope of the stream forms a periodic function. This can be looked upon as a form of amplitude modulation, generating sidebands. When several streams are added it is possible to model complex sounds such as the human voice. (Carrier = waveform within grain, modulator = grain envelope) “The sidebands are separated from the carrier by a distance equal to the inverse of the period of the envelope function. For a stream of 20ms grains following each other the sidebands in the output spectrum are spaced at 50Hz intervals.” (Roads) We can think of QSGS as amplitude modulation since AM occurs when the shape of a signal, the modulator affects that of another, the carrier The effect of amplitude modulation can be thought of as formant synthesis, similar to methods used in speech synthesis such as FOF (formes d’ondes formantiques). FOF synthesis was developed at IRCAM as the basis for the CHANT program for speech synthesis. The basic idea behind FOFs is the addition of formants in order to recreate a complex tone such as the human voice. Each grain is fed into a resonator with control over center frequency and bandwidth. http://www.sfu.ca/~truax/GranQs.gif • Asynchronous granular synthesis: Grains are distributed stochastically with no quasi regularity (Truax ‘98). The overall characteristics of each cloud is determined by the following parameters. 1. Start time and duration of the cloud 2. Grain duration (Variable for the duration of the cloud) 3. Density of grains per second (Also variable) 4. Frequency band of the cloud (Usually high and low limits) 5. Amplitude envelope of the cloud 6. Waveforms within the grains 7. Spatial dispersion of the cloud asynchronous granular synthesis http://www.sonicspace.org/ver4/GS.htm • Pitch-Synchronous Granular Synthesis: This technique was designed for the generation of sounds with one or more formants in their spectra. PSGS is an analysis synthesis technique which first requires an analysis stage involving pitch detection, where each pitch period is assigned its own grain.A spectral analysis is performed on each grain from which an impulse response is derived for the re-synthesis process. Based on the set of impulse response obtained a pulse train is generated at each pitch period and at each time frame the system emits a grain overlapped with the previous one to create a smooth time varying signal. Granulation of sampled sounds: Sampled sounds are fed into a granulator which reads a small portion of the sample and applies an envelope to it. Grains are then processed in a ‘traditional’ granular fashion, giving the composer control over the order of the grains, density of the streams etc… Csound has several opcodes allowing for the granulation of sampled sounds: granule, grain, fog among others. Fourier and wavelet grids: “These techniques take in a time-domain sound signal and measure its frequency content versus time. Each point in the analysis is associated with a unit of time-frequency energy.” (Roads) These are primarily analysis-resynthesis techniques which are well suited to the transformation of sampled sounds, the most obvious application being time stretching or compression and transposition. The grain envelope is central to all granular synthesis techniques and has profound implications on the overall spectrum generated. The envelope applied to each grain prevents pops and clicks from showing up in the final output. Changing the shape/slope of the envelope also has a direct consequence on the sound being generated, sharper attacks producing broader bandwidth. (Truax) The envelope for each grain varies widely from simple AD envelopes, to Gaussian, bell like shapes. Gaussian envelopes Hanning window a. Gaussian b. Quasi Gausian c. Tree Stage Line segment d. Triangular e. Sin function f. Expodec g. Rexpodec When granulated sounds (concrete) are played thru a rexpodec envelopes they tend to sound reversed. Humans have difficulties in perceiving pitch in sounds below 50 ms Below 2ms, grains tend to sound like clicks Even with durations this short varying the waveform and shape of the Envelope will affect the tone color of the click (Roads ‘96) Pitch perception in relation to grain duration: 2ms 5ms 25ms 50ms ---------|--------------------|--------------------------|---------------------------------------> clicks vague clearer clear When using synchronous techniques metric rhythms are produced when grains Are fired at a rate of 0.1 to 20 per seconds. (density) Above 20 grains per second the grains fuse into a continuous tone. Depending on the grain envelope and duration the streams may also exhibit Sidebands or formants. The perceived pitch of a synchronous stream depends on: a. The period corresponding to the frequency of the waveform in the grain b. The period corresponding to the grain envelope c. The period corresponding to the grain density (Roads ‘96) Roads: “The grain envelope contributes an Amplitude Modulation effect. Sidebands around the carrier frequency are generated at intervals of the envelope’s period. Therefore: For a given grain duration D, the center frequency of AM in an asynchronous Cloud will be 1/D The laws of micro-acoustics tell us that the shorter the duration of a signal, the greater its bandwidth, Thus the width of the frequency bands B caused by the sidebands is inversely proportional to the duration of the grain D.” In Short: The longer the grain length, the lower the sidebands frequency “Although the internal structure of sounds is the cause of what we hear , we do not resolve this structure in our perception. The experience of a grain is indivisible” (Wishart ‘94) The time reversibility properties of a grain only hold true if: 1. the grain envelope is symetrical 2. the grain waveform is static 3. the waveform of all grains is identical 4. the cloud/stream’s density is kept constant “Granular synthesis using Csound can be achieved by using conditional statements or a combination of existing units generator, but this is complicated and would require a large orchestra and score file to generate a short output.” Allan S. C. Lee Csound provides an extensive set of tools for granular synthesis, the following are only listed as a reference and not meant to be an extensive list of granular opcodes. syncgrain: synchronous granular synthesis Syncgrain implements synchronous granular synthesis. The source sound for the grains is obtained by reading a function table containing the samples of the source waveform. For sampled-sound sources, GEN01 is used. Syncgrain will accept deferred allocation tables (with aif files). grain: Generates simple granular textures. grain3:Generates granular textures with more user control than grain. granule: A more complex granular synthesizer. granule is a Csound unit generator which employs a wavetable as input to produce granularly synthesized audio output. Wavetable data may be generated by any of the GEN subroutines such as GEN01 which reads an audio data file into a wavetable. This enable a sampled sound to be used as the source for the grains. Up to 128 voices are implemented internally. sndwarp: sndwarp reads sound samples from a table and applies time-stretching and/or pitch modification. Time and frequency modification are independent from one another. For example, a sound can be stretched in time while raising the pitch fof: Produces sinusoid bursts useful for formant and granular synthesis. fof2: Produces sinusoid bursts including k-rate incremental indexing with each successive burst, making it more suitable for time warping applications fof: Produces sinusoid bursts useful for formant and granular synthesis. syncloop: a variation on syncgrain, which implements synchronous granular synthesis. Syncloop adds loop start and end points and an optional start position A simple implementation of granular synthesis: res grain xamp, xpitch, xdens, kampoff, kpitchoff, kgdur, igfn, iwfn, imgdur [, igrnd] An exhaustive implementation of granular synthesis: ares granule xamp, ivoice, iratio, imode, ithd, ifn, ipshift, igskip, igskip_os, ilength, kgap, igap_os, kgsize, igsize_os, iatt, idec [, iseed] [, ipitch1] [, ipitch2] [, ipitch3] [, ipitch4] [, ifnenv] With 22 parameters the granule opcode gives the sound designer a lot of control over The synthesis proccess, although the opcode is not as daunting as it first appears as most of Its parameters are I-rate.
Load more

Recommended publications
  • Granular Synthesis and Physical Modeling with This Manual Is Released Under the Creative Commons Attribution 3.0 Unported License
    Granular synthesis and physical modeling with This manual is released under the Creative Commons Attribution 3.0 Unported License. You may copy, distribute, transmit and adapt it, for any purpose, provided you include the following attribution: Kaivo and the Kaivo manual by Madrona Labs. http://madronalabs.com. Version 1.3, December 2016. Written by George Cochrane and Randy Jones. Illustrated by David Chandler. Typeset in Adobe Minion using the TEX document processing system. Any trademarks mentioned are the sole property of their respective owners. Such mention does not imply any endorsement of or associa- tion with Madrona Labs. Introduction “The future evolution of virtual devices is less constrained than that of real devices.” –Julius O. Smith Kaivo is a software instrument combining two powerful synthesis techniques (physical modeling and granular synthesis) in an easy-to- use semi-modular package. It’s laid out a bit like an acoustic instru- For more information on the theory be- ment; the GRANULATOR module acts like the player’s touch, exciting hind Kaivo, see Chapter 1, “Physi-who? Granu-what?” one or more tuned objects (here, the RESONATOR module, based on physical models of resonant objects) that come together in a central resonating body (the BODY module, also physics-based). This allows for a natural (or uncanny) sense of space, pleasing in- teractions between voices, and a ton of expressive potential—all traits in short supply in digital synthesis. The acoustic comparison begins to pale when you realize that your “touch” is really a granular sam- ple player with scads of options, and that the physical properties of the resonating modules are widely variable, and in real time.
    [Show full text]
  • The Sonification Handbook Chapter 9 Sound Synthesis for Auditory Display
    The Sonification Handbook Edited by Thomas Hermann, Andy Hunt, John G. Neuhoff Logos Publishing House, Berlin, Germany ISBN 978-3-8325-2819-5 2011, 586 pages Online: http://sonification.de/handbook Order: http://www.logos-verlag.com Reference: Hermann, T., Hunt, A., Neuhoff, J. G., editors (2011). The Sonification Handbook. Logos Publishing House, Berlin, Germany. Chapter 9 Sound Synthesis for Auditory Display Perry R. Cook This chapter covers most means for synthesizing sounds, with an emphasis on describing the parameters available for each technique, especially as they might be useful for data sonification. The techniques are covered in progression, from the least parametric (the fewest means of modifying the resulting sound from data or controllers), to the most parametric (most flexible for manipulation). Some examples are provided of using various synthesis techniques to sonify body position, desktop GUI interactions, stock data, etc. Reference: Cook, P. R. (2011). Sound synthesis for auditory display. In Hermann, T., Hunt, A., Neuhoff, J. G., editors, The Sonification Handbook, chapter 9, pages 197–235. Logos Publishing House, Berlin, Germany. Media examples: http://sonification.de/handbook/chapters/chapter9 18 Chapter 9 Sound Synthesis for Auditory Display Perry R. Cook 9.1 Introduction and Chapter Overview Applications and research in auditory display require sound synthesis and manipulation algorithms that afford careful control over the sonic results. The long legacy of research in speech, computer music, acoustics, and human audio perception has yielded a wide variety of sound analysis/processing/synthesis algorithms that the auditory display designer may use. This chapter surveys algorithms and techniques for digital sound synthesis as related to auditory display.
    [Show full text]
  • Combining Granular Synthesis with Frequency Modulation
    Combining granular synthesis with frequency modulation. Kim ERVIK Øyvind BRANDSEGG Department of music Department of music University of Science and Technology University of Science and Technology Norway Norway [email protected] [email protected] Abstract acoustical events. Sound as particles has been Both granular synthesis and frequency used in applications like independent time and modulation are well-established synthesis pitch scaling, formant modification, analog synth techniques that are very flexible. This paper modeling, clouds of sound, granular delays and will investigate different ways of combining reverbs, etc [3]. Examples of granular synthesis the two techniques. It will describe the rules parameters are density, grain pitch, grain duration, of spectra that emerge when combining, compare it to similar synthesis techniques and grain envelope, the global arrangement of the suggest some aesthetic perspectives on the grains, and of course the content of the grains matter. (which can be a synthetic waveform or sampled sound). Granular synthesis gives the musician vast Keywords expressive possibilities [10]. Granular synthesis, frequency modulation, 1.3 FM synthesis partikkel, csound, sound synthesis Frequency modulation has been a known method of coding audio into radio signal since the beginning of commercial radio. In 1964 that John Chowning discovered the implication of frequency modulation of audio working on synthesis of brass instrument at Stanford [2]. He discovered that modulating the frequency resulted in sideband emerging from the carrier frequency. Fig 1:Grain Pitch modulation Yamaha later implemented the technique in the hugely successful DX7. 1 Introduction If we consider FM synthesis using sinusoidal carrier and modulation oscillator, the spectral 1.1 Method components present in a FM sound can be mathematically stated as in figure 2.
    [Show full text]
  • Neural Granular Sound Synthesis
    Neural Granular Sound Synthesis Adrien Bitton Philippe Esling Tatsuya Harada IRCAM, CNRS UMR9912 IRCAM, CNRS UMR9912 The University of Tokyo, RIKEN Paris, France Paris, France Tokyo, Japan [email protected] [email protected] [email protected] ABSTRACT Granular sound synthesis is a popular audio generation technique based on rearranging sequences of small wave- resynthesis generated sequence match decode form windows. In order to control the synthesis, all grains grains in a given corpus are analyzed through a set of acoustic continuous + f(↵) descriptors. This provides a representation reflecting some discrete + condition + form of local similarities across the grains. However, the grain space + quality of this grain space is bound by that of the descrip- + + + grain tors. Its traversal is not continuously invertible to signal grain + + latent space sample and does not render any structured temporality. library dz acoustic R We demonstrate that generative neural networks can im- analysis encode plement granular synthesis while alleviating most of its target signal shortcomings. We efficiently replace its audio descriptor input basis by a probabilistic latent space learned with a Vari- signal ational Auto-Encoder. In this setting the learned grain space is invertible, meaning that we can continuously syn- thesize sound when traversing its dimensions. It also im- Figure 1. Left: A grain library is analysed and scattered (+) into the acoustic dimensions. A target is defined, by analysing an other signal (o) plies that original grains are not stored for synthesis. An- or as a free trajectory, and matched to the library through the acoustic other major advantage of our approach is to learn struc- descriptors.
    [Show full text]
  • Concatenative Sound Synthesis: the Early Years
    CONCATENATIVE SOUND SYNTHESIS: THE EARLY YEARS Diemo Schwarz Ircam – Centre Pompidou 1, place Igor-Stravinsky, 75003 Paris, France http://www.ircam.fr/anasyn/schwarz http://concatenative.net [email protected] ABSTRACT Concatenative sound synthesis (CSS) methods use a large database of source sounds, segmented into units, Concatenative sound synthesis is a promising method and a unit selection algorithm that finds the sequence of of musical sound synthesis with a steady stream of work units that match best the sound or phrase to be synthe- and publications for over five years now. This article of- sised, called the target. The selection is performed ac- fers a comparative survey and taxonomy of the many dif- cording to the descriptors of the units, which are charac- ferent approaches to concatenative synthesis throughout teristics extracted from the source sounds, or higher level the history of electronic music, starting in the 1950s, even descriptors attributed to them. The selected units can then if they weren't known as such at their time, up to the recent be transformed to fully match the target specification, and surge of contemporary methods. Concatenative sound are concatenated. However, if the database is sufficiently synthesis methods use a large database of source sounds, large, the probability is high that a matching unit will be segmented into units, and a unit selection algorithm that found, so the need to apply transformations, which always finds the units that match best the sound or musical phrase degrade sound quality, is reduced. The units can be non- to be synthesised, called the target. The selection is per- uniform (heterogeneous), i.e.
    [Show full text]
  • Chroma Palette: Chromatic Maps of Sound As Granular Synthesis
    Proceedings of the 2007 Conference on New Interfaces for Musical Expression (NIME07), New York, NY, USA Chroma Palette: Chromatic Maps of Sound As Granular Synthesis Interface Justin Donaldson Ian Knopke Chris Raphael Indiana University School of Indiana University School of Indiana University School of Informatics Informatics Informatics 1900 E. 10th Street, Room 931 1900 E. 10th Street, Room 932 1900 E. 10th Street, Room 933 Bloomington, IN 47406 Bloomington, IN 47406 Bloomington, IN 47406 [email protected] [email protected] [email protected] ABSTRACT There are many different categories of granular synthesis, Chroma based representations of acoustic phenomenon are such as synchronous, quasi-synchronous, and asynchronous representations of sound as pitched acoustic energy. A frame- forms, referring to the regularity with which grains are wise chroma distribution over an entire musical piece is a useful reassembled. Grains are usually windowed, both to aid resynthesis and straightforward representation of its musical pitch over time. and to avoid audible clicks. However, the choice of window This paper examines a method of condensing the block-wise function can also have a pronounced effect on the resulting timbre chroma information of a musical piece into a two dimensional and is an important component of the synthesis process. Granular embedding. Such an embedding is a representation or map of the synthesis has similarities to other common analysis/resynthesis different pitched energies in a song, and how these energies relate methodologies such as the short-term Fourier transform and to each other in the context of the song. The paper presents an wavelet-based techniques. Figure 1 shows an example of an interactive version of this representation as an exploratory envelope windowing and overlap arrangement for four different analytical tool or instrument for granular synthesis.
    [Show full text]
  • NUMERICAL SOUND SYNTHESIS Ii Numerical Sound Synthesis
    NUMERICAL SOUND SYNTHESIS ii Numerical Sound Synthesis Stefan Bilbao November 27, 2007 iii iv Contents Preface xiii 1 Sound Synthesis and Physical Modeling 1 1.1 AbstractDigitalSoundSynthesis . .......... 2 1.1.1 AdditiveSynthesis . .. .. .. .. .. .. .. .. .. .. .. .. .... 3 1.1.2 SubtractiveSynthesis . ..... 5 1.1.3 WavetableSynthesis . .... 5 1.1.4 AMandFMSynthesis.............................. 7 1.1.5 OtherMethods .................................. 8 1.2 PhysicalModeling ................................ ..... 9 1.2.1 LumpedMass-SpringNetworks . ..... 10 1.2.2 ModalSynthesis ................................ .. 11 1.2.3 DigitalWaveguides. .... 13 1.2.4 HybridMethods ................................. 16 1.2.5 DirectNumericalSimulation . ...... 17 1.3 PhysicalModeling: ALargerView . ........ 20 1.3.1 Physical Models as Descended from Abstract Synthesis ............ 20 1.3.2 Connections: Direct Simulation and Other Methods . ........... 21 1.3.3 ComplexityofMusicalSystems . ...... 22 1.3.4 Why? ........................................ 25 2 Time Series and Difference Operators 27 2.1 TimeSeries ...................................... ... 28 2.2 Shift, Difference and AveragingOperators . ............ 29 2.2.1 TemporalWidth ofDifference Operators. ........ 30 2.2.2 CombiningDifferenceOperators . ...... 31 2.2.3 TaylorSeriesandAccuracy . ..... 32 2.2.4 Identities .................................... .. 33 2.3 FrequencyDomainAnalysis . ....... 34 2.3.1 Laplace and z transforms ............................. 34 2.3.2 Frequency Domain Interpretation
    [Show full text]
  • Physically-Based Parametric Sound Synthesis and Control
    Physically-Based Parametric Sound Synthesis and Control Perry R. Cook Princeton Computer Science (also Music) Course Introduction Parametric Synthesis and Control of Real-World Sounds for virtual reality games production auditory display interactive art interaction design Course #2 Sound - 1 Schedule 0:00 Welcome, Overview 0:05 Views of Sound 0:15 Spectra, Spectral Models 0:30 Subtractive and Modal Models 1:00 Physical Models: Waveguides and variants 1:20 Particle Models 1:40 Friction and Turbulence 1:45 Control Demos, Animation Examples 1:55 Wrap Up Views of Sound • Sound is a recorded waveform PCM playback is all we need for interactions, movies, games, etc. (Not true!!) • Time Domain x( t ) (from physics) • Frequency Domain X( f ) (from math) • Production what caused it • Perception our image of it Course #2 Sound - 2 Views of Sound Time Domain is most closely related to Production Frequency Domain is most closely related to Perception we will see that many hybrids abound Views of Sound: Time Domain Sound is produced/modeled by physics, described by quantities of • Force force = mass * acceleration • Position x(t) actually < x(t), y(t), z(t) > • Velocity Rate of change of position dx/dt • Acceleration Rate of change of velocity dv/dt Examples: Mass+Spring+Damper Wave Equation Course #2 Sound - 3 Mass/Spring/Damper F = ma = - ky - rv - mg F = ma = - ky - rv (if gravity negligible) d 2 y r dy k + + y = 0 dt2 m dt m ( ) D2 + Dr / m + k / m = 0 2nd Order Linear Diff Eq. Solution 1) Underdamped: -t/τ ω y(t) = Y0 e cos( t ) exp.
    [Show full text]
  • Soft Sound: a Guide to the Tools and Techniques of Software Synthesis
    California State University, Monterey Bay Digital Commons @ CSUMB Capstone Projects and Master's Theses Spring 5-20-2016 Soft Sound: A Guide to the Tools and Techniques of Software Synthesis Quinn Powell California State University, Monterey Bay Follow this and additional works at: https://digitalcommons.csumb.edu/caps_thes Part of the Other Music Commons Recommended Citation Powell, Quinn, "Soft Sound: A Guide to the Tools and Techniques of Software Synthesis" (2016). Capstone Projects and Master's Theses. 549. https://digitalcommons.csumb.edu/caps_thes/549 This Capstone Project is brought to you for free and open access by Digital Commons @ CSUMB. It has been accepted for inclusion in Capstone Projects and Master's Theses by an authorized administrator of Digital Commons @ CSUMB. Unless otherwise indicated, this project was conducted as practicum not subject to IRB review but conducted in keeping with applicable regulatory guidance for training purposes. For more information, please contact [email protected]. California State University, Monterey Bay Soft Sound: A Guide to the Tools and Techniques of Software Synthesis Quinn Powell Professor Sammons Senior Capstone Project 23 May 2016 Powell 2 Introduction Edgard Varèse once said: “To stubbornly conditioned ears, anything new in music has always been called noise. But after all, what is music but organized noises?” (18) In today’s musical climate there is one realm that overwhelmingly leads the revolution in new forms of organized noise: the realm of software synthesis. Although Varèse did not live long enough to see the digital revolution, it is likely he would have embraced computers as so many millions have and contributed to these new forms of noise.
    [Show full text]
  • The Evolution of Granular Synthesis: an Overview of Current Research
    International Symposium on The Creative and Scientific Legacies of Iannis Xenakis, 8-10 June 2006, University of Guelph, Toronto, Canada ________________________________________________________ The evolution of granular synthesis: an overview of current research Curtis Roads Media Arts and Technology University of California Santa Barbara CA 93106-6065 USA 9 June 2006 This lecture presents an overview of several projects pursued over the past five years in our laboratories at Santa Barbara. All this research is based on a scientific model of sound initially proposed by Dennis Gabor (1946), and soon afterward extended to music by Iannis Xenakis (1960). Granular analysis (also called atomic decomposition) and granular synthesis have evolved over more than five decades from a paper theory and primitive experiments into a broad range of applied techniques. Specific to the granular model is its focus on the microacoustic time scale (typically 1 to 100 ms). Granular methods treat sound as a stream of acoustic particles in both the time domain and the time-frequency (TF) domain. For more details, see Roads (2002; Kling, et al. 2005). In this lecture, I first very briefly trace the history of the idea of sound particles. Next I will demonstrate PulsarGenerator, an application developed by Alberto de Campo and me in 2001 for a specific type of particle synthesis with links to past analog techniques. I will also demonstrate the SweepingQGranulator, a tool that I wrote in the SuperCollider language for the microfiltration of granulated sound. The latest threads in this line of research go in two directions. The first is a time-frequency analysis method known as matching pursuit decomposition.
    [Show full text]
  • Morphing of Granular Sounds
    Proc. of the 18th Int. Conference on Digital Audio Effects (DAFx-15), Trondheim, Norway, Nov 30 - Dec 3, 2015 MORPHING OF GRANULAR SOUNDS Sadjad Siddiq Advanced Technology Division, Square Enix Co., Ltd. Tokyo, Japan [email protected] ABSTRACT Granular sounds are commonly used in video games but the con- ventional approach of using recorded samples does not allow sound designers to modify these sounds. In this paper we present a tech- nique to synthesize granular sound whose tone color lies at an arbi- trary point between two given granular sound samples. We first ex- tract grains and noise profiles from the recordings, morph between them and finally synthesize sound using the morphed data. Dur- ing sound synthesis a number of parameters, such as the number of grains per second or the loudness distribution of the grains, can be altered to vary the sound. The proposed method does not only al- low to create new sounds in real-time, it also drastically reduces the Figure 1: Summary of granular synthesis. Grains are at- memory footprint of granular sounds by reducing a long recording tenuated and randomly added to the final mix. to a few hundred grains of a few milliseconds length each. simplest case their amplitude is attenuated randomly. Depending 1. INTRODUCTION on the probability distribution of the attenuation factors, this can 1.1. Granular synthesis in video games have a very drastic effect on the granularity and tone color of the produced sound. For a more detailed introduction to granular syn- In previous work we described the morphing between simple im- thesis refer to [4] or [5].
    [Show full text]
  • CM3106 Chapter 5: Digital Audio Synthesis
    CM3106 Chapter 5: Digital Audio Synthesis Prof David Marshall [email protected] and Dr Kirill Sidorov [email protected] www.facebook.com/kirill.sidorov School of Computer Science & Informatics Cardiff University, UK Digital Audio Synthesis Some Practical Multimedia Digital Audio Applications: Having considered the background theory to digital audio processing, let's consider some practical multimedia related examples: Digital Audio Synthesis | making some sounds Digital Audio Effects | changing sounds via some standard effects. MIDI | synthesis and effect control and compression Roadmap for Next Few Weeks of Lectures CM3106 Chapter 5: Audio Synthesis Digital Audio Synthesis 2 Digital Audio Synthesis We have talked a lot about synthesising sounds. Several Approaches: Subtractive synthesis Additive synthesis FM (Frequency Modulation) Synthesis Sample-based synthesis Wavetable synthesis Granular Synthesis Physical Modelling CM3106 Chapter 5: Audio Synthesis Digital Audio Synthesis 3 Subtractive Synthesis Basic Idea: Subtractive synthesis is a method of subtracting overtones from a sound via sound synthesis, characterised by the application of an audio filter to an audio signal. First Example: Vocoder | talking robot (1939). Popularised with Moog Synthesisers 1960-1970s CM3106 Chapter 5: Audio Synthesis Subtractive Synthesis 4 Subtractive synthesis: Simple Example Simulating a bowed string Take the output of a sawtooth generator Use a low-pass filter to dampen its higher partials generates a more natural approximation of a bowed string instrument than using a sawtooth generator alone. 0.5 0.3 0.4 0.2 0.3 0.1 0.2 0.1 0 0 −0.1 −0.1 −0.2 −0.2 −0.3 −0.3 −0.4 −0.5 −0.4 0 2 4 6 8 10 12 14 16 18 20 0 2 4 6 8 10 12 14 16 18 20 subtract synth.m MATLAB Code Example Here.
    [Show full text]