Sound Synthesis for Physics-based Computer Animation PDF Download

Author: Jeffrey Neil Chadwick
Publisher:
ISBN:
Category :
Languages : en
Pages : 147

View

Book Description
In this thesis, we explore the problem of synthesizing realistic soundtracks for physicsbased computer animations. While the problem of producing realistic animations of physical phenomena has received much attention over the last few decades, comparatively little attention has been devoted to the problem of generating synchronized soundtracks for these simulations. Recent work on sound synthesis in the computer graphics community has largely focused on producing sound for simple, rigid-body animations. While these methods have been successful for certain scenes, the range of examples for which they produce convincing results is quite limited. In this thesis, we introduce a variety of new sound synthesis algorithms suitable for generating physics-based animation soundtracks. We demonstrate synthesis results on a variety of animated scenes for which prior methods are incapable of producing plausible sounds. First, we introduce a new algorithm for synthesizing sound due to nonlinear vibrations in thin shell structures. Our contributions include a new thin shell-based dimensional model reduction approach for efficiently simulating thin shell vibrations. We also provide a novel data-driven model for acoustic transfer due to vibrating objects, allowing for very fast sound synthesis once object vibrations are known. We find that this sound synthesis method produces significantly more realistic results than prior rigidbody sound synthesis algorithms for a variety of familiar objects. Next, we further address the limitations of prior sound synthesis techniques by introducing a new method for synthesizing rigid-body acceleration noise - sound produced when an object experiences rapid rigid-body acceleration. We develop an effi- cient impulse-based model for synthesizing sound due to arbitrary rigid-body accelerations and build a system for modeling plausible rigid-body accelerations due to contact events in a standard rigid-body dynamics solver. This allows us to efficiently recover acceleration sound using data readily available from rigid-body simulations. Our results demonstrate that our method significantly improves upon the results available when using traditional rigid-body sound synthesis with no acceleration noise modeling. We also introduce a scalable proxy model which provides us with a practical method for synthesizing acceleration sound from scenes with hundreds to thousands of unique objects. This allows us to produce substantially improved sound results for phenomena such as rigid-body fracture. Finally, we also consider sound from other, non-rigid phenomena; specifically, sound from physics-based animations of fire. We propose a hybrid sound synthesis algorithm combining physics-based and data-driven approaches. Our method produces plausible results for a variety of fire animations. Moreover, our use of data-driven synthesis grants users of our method a degree of artistic control.

Author: Changxi Zheng
Publisher:
ISBN:
Category :
Languages : en
Pages : 214

View

Book Description
The real world is full of sounds: a babbling brook winding through a tranquil forest, an agitated shopping cart plugging down a flight of stairs, or a falling piggybank breaking on the ground. Unfortunately virtual worlds simulated by current simulation algorithms are still inherently silent. Sounds are added as afterthoughts, often using "canned sounds" which have little to do with the animated geometry and physics. While recent decades have seen dramatic success of 3D computer animation, our brain still expects a full spectrum of sensations. The lack of realistic sound rendering methods will continue to cripple our ability to enable highly interactive and realistic virtual experiences as computers become faster. This dissertation presents a family of algorithms for procedural sound synthesis for computer animation. These algorithms are built on physics-based simulation methods for computer graphics, simulating both the object vibrations for sound sources and sound propagation in virtual environments. These approaches make it feasible to automatically generate realistic sounds synchronized with animated dynamics. Our first contribution is a physically based algorithm for synthesizing sounds synchronized with brittle fracture animations. Extending time-varying rigid-body sound models, this method first resolves near-audio-rate fracture events using a fast quasistatic elastic stress solver, and then estimates fracture patterns and resulting fracture impulses using an energy-based model. To make it practical for a large number of fracture debris, we exploit human perceptual ambiguity when synthesizing sounds from many objects, and propose to use pre-computed sound proxies for reduced cost of sound-model generation. We then introduce a contact sound model for improved sound quality. This method captures very detailed non-rigid sound phenomena by resolving modal vibrations in both collision and frictional contact processing stages, thereby producing contact sounds with much richer audible details such as micro-collisions and chattering. This algorithm is practical, enabled by a novel asynchronous integrator with model-level adaptivity built into a frictional contact solver. Our third contribution focuses on another major type of sound phenomena, fluid sounds. We propose a practical method for automatic synthesis of bubblebased fluid sounds from fluid animations. This method first acoustically augments existing incompressible fluid solvers with particle-based models for bubble creation, vibration, and advection. To model sound propagation in both fluid and air domain, we weight each single-bubble sound by its bubble-to-ear acoustic transfer function value, which is modeled as a discrete Green's function of the Helmholtz equation. A fast dual-domain multipole boundary-integral solver is introduced for hundreds of thousands of Helmholtz solves in a typical babbling fluid simulation. Finally, we switch gear and present a fast self-collision detection method for deforming triangle meshes. This method can accelerate deformable simulations and lead to faster sound synthesis of deformable phenomena. Inspired by a simple idea that a mesh cannot self collide unless it deforms enough, this method supports arbitrary mesh deformations while still being fast. Given a bounding volume hierarchy (BVH) for a triangle mesh, we operate on bounding-volume-related submeshes, and precompute Energy-based Self- Collision Culling (ESCC) certificates, which indicate the amount of deformation energy required for the submesh to self collide. After updating energy values at runtime, many bounding-volume self-collision queries can be culled using the ESCC certificates. We propose an affine-frame Laplacian-based energy definition which sports a highly optimized certificate preprocess and fast runtime energy evaluation.

Author: Jui-Hsien Wang
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description
Physics-based sound synthesis is an increasingly popular technique in computer graphics to automatically generate realistic sounds associated to (otherwise silent) visual events, such as a spolling green plastic bowl or a dripping faucet. Previous work has shown very promising results; however, these algorithms still suffer from several shortcomings, such as long precomputation time or difficult integration for complex sound sources. In this thesis, we explore new simulation frameworks that leverage time-domain methods and insights to improve both the quality and speed of physics-based sound synthesis algorithms. First, we introduce KleinPAT, a new time-domain algorithm that rapidly estimates acoustic transfer fields of a vibrating rigid object (modeled by the linear modal model). Instead of estimating the transfer fields by (sequentially) solving the frequency-domain Helmholtz equations, our method partitions all vibration modes into chords using optimal mode conflation, performs a single time-domain wave simulation for each chord, and then separates the per-mode transfer fields using a deconflation solver. We show that our method achieves thousand-fold speedup compared to the more traditional fast boundary element methods, and maintains accuracy suitable for sound synthesis. Second, we present an integrated time-domain acoustic wavesolver to support sound rendering of a wide variety of physics-based simulation models and computer animated phenomena. We target high-quality offline rendering, and introduce methods including a sharp-interface boundary handling method, the acoustic shaders abstraction to integrate various sound sources, and a parallel-in-time synthesis algorithm for this task. We demonstrate the generality and quality of the solver by rendering sound sources of dynamic, multi-physics nature, such as vibrating solids, thin shells, water, and character. Finally, we will switch gears and introduce a new method to enrich standard rigid-body impact models with spatially varying coefficient of restitution maps, or Bounce Maps. We demonstrate that the commonly accepted hypothesis of constant restitution value per object is wildly incorrect, and propose a fast precomputation algorithm to sample and compute it. The resulting Bounce Maps can be queried in negligible time and can be used easily to enhance existing solvers. Although it is not directly related to sound synthesis, we will show that a dominant factor for varying restitution responses is the post-impact vibrations, which can cause sound.

Author: Shiguang Liu
Publisher: Morgan & Claypool Publishers
ISBN: 1636393217
Category : Computers
Languages : en
Pages : 110

View

Book Description
This book gives a broad overview of research on sound simulation driven by a variety of applications. Vibrating objects produce sound, which then propagates through a medium such as air or water before finally being heard by a listener. As a crucial sensory channel, sound plays a vital role in many applications. There is a well-established research community in acoustics that has studied the problems related to sound simulation for six decades. Some of the earliest work was motivated by the design of concert halls, theaters, or lecture rooms with good acoustic characteristics. These problems also have been investigated in other applications, including noise control and sound design for urban planning, building construction, and automotive applications. Moreover, plausible or realistic sound effects can improve the sense of presence in a virtual environment or a game. In these applications, sound can provide important clues such as source directionality and spatial size. The book first surveys various sound synthesis methods, including harmonic synthesis, texture synthesis, spectral analysis, and physics-based synthesis. Next, it provides an overview of sound propagation techniques, including wave-based methods, geometric-based methods, and hybrid methods. The book also summarizes various techniques for sound rendering. Finally, it surveys some recent trends, including the use of machine learning methods to accelerate sound simulation and the use of sound simulation techniques for other applications such as speech recognition, source localization, and computer-aided design.

Author: Liu Shiguang
Publisher: Springer Nature
ISBN: 3031792149
Category : Mathematics
Languages : en
Pages : 96

View

Book Description
This book gives a broad overview of research on sound simulation driven by a variety of applications. Vibrating objects produce sound, which then propagates through a medium such as air or water before finally being heard by a listener. As a crucial sensory channel, sound plays a vital role in many applications. There is a well-established research community in acoustics that has studied the problems related to sound simulation for six decades. Some of the earliest work was motivated by the design of concert halls, theaters, or lecture rooms with good acoustic characteristics. These problems also have been investigated in other applications, including noise control and sound design for urban planning, building construction, and automotive applications. Moreover, plausible or realistic sound effects can improve the sense of presence in a virtual environment or a game. In these applications, sound can provide important clues such as source directionality and spatial size. The book first surveys various sound synthesis methods, including harmonic synthesis, texture synthesis, spectral analysis, and physics-based synthesis. Next, it provides an overview of sound propagation techniques, including wave-based methods, geometric-based methods, and hybrid methods. The book also summarizes various techniques for sound rendering. Finally, it surveys some recent trends, including the use of machine learning methods to accelerate sound simulation and the use of sound simulation techniques for other applications such as speech recognition, source localization, and computer-aided design.

Author: Adam Bognat
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description
"Physics-based audio synthesis is finding increasingly diverse applications within computer graphics and animation. Conventional approaches based in modal synthesis are appropriate for simulations of rigid body contact sounds and large deformable objects, but are ill-suited for other primitives such as elastic rods and thin shells due to the non-linear effects that come with large displacements and the computational cost associated with highly refined meshes. In this thesis, we describe a software framework for the simulation of elastic rods and generation of sound from their motion that overcomes these limitations. A discrete elastic rod model based in Kirchhoff theory is used in simulating the rod dynamics, and a dipole source model is used to compute acoustic pressure values in the far-field. We consider a number of test systems to illustrate the fundamentals of the rod model and the variety of sounds that may be produced with a few free parameters. " --

Author: Cécile Picard Limpens
Publisher:
ISBN:
Category :
Languages : en
Pages : 162

View

Book Description
The main objective of this thesis is to provide tools for an expressive and real-time synthesis of sounds resulting from physical interactions of various objects in a 3D virtual environment. Indeed, these sounds, such as collisions sounds or sounds from continuous interaction between surfaces, are difficult to create in a pre-production process since they are highly dynamic and vary drastically depending on the interaction and objects. To achieve this goal, two approaches are proposed; the first one is based on simulation of physical phenomena responsible for sound production, the second one based on the processing of a recordings database. According to a physically based point of view, the sound source is modelled as the combination of an excitation and a resonator. We first present an original technique to model the interaction force for continuous contacts, such as rolling. Visual textures of objects in the environment are reused as a discontinuity map to create audible position-dependent variations during continuous contacts. We then propose a method for a robust and flexible modal analysis to formulate the resonator. Besides allowing to handle a large variety of geometries and proposing a multi-resolution of modal parameters, the technique enables us to solve the problems of coherence between physics simulation and sound synthesis that are frequently encountered in animation. Following a more empirical approach, we propose an innovative method that consists in bridging the gap between direct playback of audio recordings and physically based synthesis by retargetting audio grains extracted from recordings according to the output of a physics engine. In an off-line analysis task, we automatically segment audio recordings into atomic grains and we represent each original recording as a compact series of audio grains. During interactive animations, the grains are triggered individually or in sequence according to parameters reported from the physics engine and/or userdefined procedures. Finally, we address fracture events which commonly appear in virtual environments, especially in video games. Because of their complexity that makes a purely physical-based model prohibitively expensive and an empirical approach impracticable for the large variety of micro-events, this thesis opens the discussion on a hybrid model and the possible strategies to combine a physically based approach and an empirical approach. The model aims at appropriately rendering the sound corresponding to the fracture and to each specific sounding sample when material breaks into pieces.

Author: Perry R. Cook
Publisher: CRC Press
ISBN: 1498765467
Category : Computers
Languages : en
Pages : 263

View

Book Description
Virtual environments such as games and animated and "real" movies require realistic sound effects that can be integrated by computer synthesis. The book emphasizes physical modeling of sound and focuses on real-world interactive sound effects. It is intended for game developers, graphics programmers, developers of virtual reality systems and traini

Author: Nadia Magnenat-Thalmann
Publisher: Springer Nature
ISBN: 3030618641
Category : Computers
Languages : en
Pages : 556

View

Book Description
This book constitutes the refereed proceedings of the 37th Computer Graphics International Conference, CGI 2020, held in Geneva, Switzerland, in October 2020. The conference was held virtually. The 43 full papers presented together with 3 short papers were carefully reviewed and selected from 189 submissions. The papers address topics such as: virtual reality; rendering and textures; augmented and mixed reality; video processing; image processing; fluid simulation and control; meshes and topology; visual simulation and aesthetics; human computer interaction; computer animation; geometric computing; robotics and vision; scientific visualization; and machine learning for graphics.

Author: Ken Greenebaum
Publisher: CRC Press
ISBN: 1439864020
Category : Computers
Languages : en
Pages : 512

View

Book Description
Audio Anecdotes is a book about digital sound. It discusses analyzing, processing, creating, and recording many forms of sound and music, emphasizing the opportunities presented by digital media made possible by the arrival of inexpensive and nearly ubiquitous digital computing equipment. Applications of digital audio techniques are indispensable i