Home Theater Systems Research Articles

Optimization of loudspeaker positions for virtual auditory displays in a free-field environment

Virtual acoustic environments are created by mimicking the pressures of real acoustic sources at a listener’s ears. In this way, a listener can perceive virtual acoustic sources as coming from any desired direction. There are multiple methods to accomplish this using headphones or loudspeaker arrays, but not all are practical for everyday use. Some use cases limit the use of headphones or the number and position of loudspeakers, such as automobiles and home theater systems. These limitations also put bounds on the performance of each possible system, such as allowable head movement and the accuracy of localization. An exhaustive-search optimizer was used to find the performance of various sparse loudspeaker arrays, given a limited number of possible loudspeaker positions in a free-field environment for a single stationary listener. The optimizer sought to maximize allowable head rotation and translation and to minimize localization errors. Arrays consisting of two or four loudspeakers were considered using a spherical head model to find the necessary head-related transfer functions and cross-talk cancellation was used to create the virtual acoustic environment. From the results, pareto fronts were created that can be used to find the best loudspeaker array configuration for given design constraints.

Audio Fundamentals: Audio Magic in Movies and Our Daily Lives

Sound is an amazing attribute of nature, has a tremendous effect on humans, and is something we use to make our way through life. Sounds conjure up emotions and memories in us, which is why it is one of the most important aspects in the creative arts. Evoking a desired response is the goal in sound design and music composition. Understanding psychoacoustics (the study of how humans perceive and respond to sound) is a major key to achieving this goal. Audio is a waveform analog of the sound it represents—thus the term “Analog Audio.” The advent of Digital Audio changed the game and Digital Signal Processing (DSP) has revolutionized music and film/TV production. Digital audio was added to film distribution starting in the early 1990s. The Digital Cinema Package (DCP) finally superseded it around 2016. The Interoperable Master Format (IMF) takes this technology further for use in home mastering-an interoperable “mezzanine” format with multiple languages and versions. At the end of the day, what matters most is how it sounds. The quality of the sound system is crucial. Great sound brings people to the theater and is a big part of a true cinematic experience. For the home consumer, headphone and soundbar technology are making great strides and well-designed home theater systems can be amazing. Mobile device sound quality is getting better each year. Immersive sound is now available in all these formats as well. We now have more ways to experience movie, episodic, and music content than ever before.

A real-time 3D video analyzer for enhanced 3D audio–visual systems

With the recent advent of three-dimensional (3D) sound home theater systems (HTS), more and more TV viewers are experiencing rich, immersive auditory presence at home. In this paper, visual processing approaches are provided to make 3D audio–visual (AV) systems more realistic to the viewers. In the proposed system, a visual engine processes stereo video streams to extract a disparity map for each pair of left and right video frames. Then, the engine determines the video depth level representing each frame of the disparity map. An audio engine then gives 3D sound depth effects according to the estimated video depth, thereby making viewers’ audio–visual experiences more synchronized. Two video processing algorithms are devised to extract the video depth from each frame: one is based on object segmentation, which turns out to be too complex to be implemented in the field-programmable gate array (FPGA) employed for real-time processing; the other algorithm uses a much simpler histogram-based approach to determine the depth of each video frame, and hence, it is more suitable for FPGA implementations. Subjective listening test results support the effectiveness of the proposed approaches.

Large neighborhood search with constraint programming for a vehicle routing problem with synchronization constraints

This paper considers an extension of the vehicle routing problem with time windows, where the arrival of two vehicles at different customer locations must be synchronized. That is, one vehicle has to deliver some product to a customer, like a home theater system, while the crew on another vehicle must install it. This type of problem is often encountered in practice and is very challenging due to the interdependency among the vehicle routes, but has received little attention in the literature. A constraint programming-based adaptive large neighborhood search is proposed to solve this problem. The search abilities of the large neighborhood search and the constraint propagation abilities of constraint programming are combined to determine the feasibility of any proposed modification to the current solution. Numerical results are reported on instances derived from benchmark instances for the vehicle routing problem with time windows with up to 200 customers.

Towards eco-friendly home networking

Home networking is becoming increasingly sophisticated as users connect ever more networked devices. In the past, home networks typically consisted of a simple router and maybe a few computers. Now, high speed wireless networks are commonplace in homes with a large number of devices: TVs, game consoles, home theater systems, and even home automation systems. This is in addition to standard computing devices such as desktops, laptops, tablets, smart phones and network-attached storage. Smart homes with many wireless sensors to improve quality of life are also emerging. However, home network devices such as routers and broadband modems have been designed for maximum performance with limited consideration of energy optimization when the devices are idle or serving low bandwidth traffic. The goal of this paper is to analyze network activity of wireless home routers, investigate opportunities for energy saving, and present mechanisms for improving the energy efficiency of wireless home routers. We analyzed five week-long traces of home network traffic and identified a number of energy saving opportunities. Through detailed trace-based simulation and implementation measurements we are able to reduce the wireless energy consumption of the home router by 12–59% while incurring only minor delay of the initial packet delivery after leaving the low energy state. Modification of an actual router's behavior shows that the proposed energy optimizations are feasible with existing clients.

Implementation of 3D Sound Effects for Museums Using Raspberry Pi and Home Theatre System

In recent years, museums are exploring digital and computer technologies to enhance visitor experience and for that purpose a variety of systems for creating 3D sound effects for museums have been implemented. The growth of the performance of low-cost minicomputers leads to the issue of their integration with home theatre systems for simple implementation of 3D sound effects. This paper presents one solution for implementing 3D sound effects for auditory illusions immersive experiences in museums using the Raspberry Pi minicomputer and a home theatre system with 5.1 surround sound. With this solution it is possible to create a museum visitor detector via Raspberry Pi that uses motion detection to trigger 3D sound playing on a home theatre system. The solution was experimentally tested developing an audio system called “Auditory Illusions for Concentration Camp Museums”. The system was developed to enrich the exhibition in the Red Cross Second World War Concentration Camp Museum in the city of Niš, Serbia.

An Augmented Level of Security for Bluetooth Devices Controlled by Smart Phones and Ubiquitous Handheld Gadgets

The enormous growth of smartphones was impelled by the idea to make a mobile phone offer more than just cellular telephony. One of the prime factors that initiated the age of smartphones (e.g. iOS, Android, RIM, etc.) was inarguably the capability of wireless sharing of images, music etc. among the users; which was possible due to Bluetooth Technology (IEEE 802.15). Today customers of the cheapest phone in world demand to have an inbuilt Bluetooth stack. Apart from sharing files, especially media, Bluetooth provides us with a lot more functionality, like streaming audio to a home entertainment system, allowing to share an Internet connection over DUN profile, a remote car locking and security system, a few to mention. Though the IEEE 802.15 stack has its own security mechanism, sometimes a system might require an additional security architecture running collaboratively with the in-built security to authorize an inbound pairing request. A simple example of the authorization paradox is that the standard security mechanism cannot help a Bluetooth system that was paired to multiple devices, to decide which of the paired devices to authorize to execute a certain task. For example, a device may be required to allow a smartphone Bluetooth stack to stream audio but restrict it from transferring files. Here need of a profile specific authorization is felt but it is beyond the scope of IEEE 802.15. To understand it better, let us assume that a home theater system has a Bluetooth link which allows smart phones to stream audio to it over A2D Audio sharing profile. Such a home theater system (e.g. HT-DZ350 by Sony) can be connected to any smartphone and play the streamed music. Each time a device disconnects, the Bluetooth stack resets itself and identity of the Bluetooth stack on the smartphone is lost. Since Bluetooth radio waves can penetrate walls and windows, it may be possible that a neighbor of mine connected her smartphone to the Home theater system and played an unwanted music. Sometimes this can be fatal in some remote controlled instruments unless proper security mechanisms are installed. Proposed in this thesis is a novel, generic and extensible framework to prevent unauthorized access over Bluetooth serial port profile; which is independent of any Cryptographic algorithm or approach. The thesis also suggests different architectures for differently equipped hardware systems, because the performance of the system under an augmented security stack will be different for different devices with varying hardware resources.

End-to-end framework for 4-D broadcasting based on MPEG-V standard

Advances in media technologies brought so-called 4-D movies to your neighbour. The 4-D movies represent movies (preferably in 3-D) with additional sensory effects such as motion chairs and wind effects. We present an end-to-end framework to provide sensory effects for home theaters based on MPEG-V standard. The key technologies of the 4-D broadcasting framework, required to provide sensory effect through home theaters consist of creating sensory effects synchronized with audiovisual contents, delivering the sensory effects with content to home theater devices, recognizing home devices for rendering sensory effects, and rendering contents through home theater system with connected sensory devices in a synchronized way. This paper proposes end-to-end technology required, in addition to the conventional broadcasting framework, based on international standard of MPEG-V, specifically Part 2 to describe capabilities of the home sensory devices, Part 3 to provide contents with sensory effects, and Part 5 to command the sensory devices among other parts of MPEG-V standard.

Bayesian and behavior networks for context-adaptive user interface in a ubiquitous home environment

Modern home theater systems require users to control various devices simultaneously including a TV, audio equipment, DVD and video players, and a receiver. To perform the requested user functions in this situation, the user is required to know the functions and positions of the buttons on several remote controls. Users will become more confused if a ubiquitous home environment, which contains many mobile and stationary control devices, is realized. Therefore, the user interface should be adaptable for requested user functions and to fit a specific control device. This paper presents a context-adaptive user interface for the control of devices in ubiquitous home environment. First, we modeled the ubiquitous home environment in order to implement the context-adaptive user interface. We used a Bayesian network to predict the necessary devices in each situation and used a behavior network to select the functions that constitute an adaptive user interface in several conditions. The selected functions were used to generate an adaptive interface for each controller using a presentation template. In this paper, we implemented a ubiquitous home environment and generated a controller usage log for this environment. We confirmed that the Bayesian network effectively predicted the user requirements by evaluating the inferred results of the necessary devices based on several scenarios. Finally, we compared the adaptive user interface with the fixed user interface by surveying fourteen subjects. We confirmed that the generated adaptive user interface was more comfortable for use with typical tasks than was the fixed user interface.

Measurement of standby power for selected electrical appliances in Australia

High growth in the uptake of electrical appliances is accounting for a significant increase in electricity consumption globally. In some developed countries, standby energy alone may account for about 10% of residential electricity use. The standby power for many appliances used in Australia is still well above the national goal of 1 W or less. In this paper, field measurements taken of standby power and operating power for a range of electrical appliances are presented. It was found that the difference between minimum value and maximum value of standby power could be quite large, up to 22.13 W for home theatre systems, for example. With the exception of home audio systems, however, the annual operating energy used by most electrical appliances was generally greater than the annual standby energy. Consumer behaviour and product choice can have a significant impact on standby power and operating power, which influences both energy demand and greenhouse gas emissions.

<i>Sound Design and Science Fiction</i> (review)

William Whittington, Sound Design and Science Fiction. Austin: U of Texas P, 2007. 280pp. US$22.95.Nabeel ZuberiSf media have created a Babel of intensely affecting and strange sounds that embody beings and machines, materialise architectural textures and characterise spaces. Explorative and futurist impulses in the virtual soundscapes of radio dramas, films, television programmes and music have expanded sf 's palette of sensations and enlivened audio culture more broadly. The urge to use sounds to speculate on subjectivity and the nature of environments has co-existed with the standardisation of sonic practices within industrialised regimes of media production. This is one of the tensions running through William Whittington's examination of sound design in Hollywood sf from the late 1960s to the end of the twentieth century. Whittington defines 'sound design' as an evolving concept and broad discourse constituted in several domains: the work processes of sound production; the qualities, juxtapositions and codifications of sound effects, music, voices and other ambient sounds that make spaces on screen audible; and the spatial and experiential dimensions of sound for film viewers in exhibition sites, whether they be multiplex theatres, home-theatre systems or computers. These aspects of sound design are intertwined in chapters devoted to canonical and financially successful sf films: 2001: A Space Odyssey (Kubrick UK/US 1968), THX 1138 (Lucas US 1971), Star Wars (Lucas US 1977), Alien (UK/ US 1979), Blade Runner (Scott US/Hong Kong 1982), Terminator 2: Judgment Day (Cameron US/France 1991) and The Matrix (Wachowski brothers US/Australia 1999).Whittington's book builds on several significant strands in film studies. First, it uses published interviews by well-known sound designers and their reflections on their profession to emphasise a history of Hollywood workers. Sound design is partly rooted in the shifting divisions of labour and contested job categories in sound production as the studio system was reorganised after World War II. Recordists, Foley artists, dialogue editors, music supervisors, composers and mixers jostled with each other over the boundaries of craft and art in sound production. The element of industrial history in the book is stronger when dealing with the formative period of the late 1960s and 1970s, but falls away a little when discussing the later films. The anecdotal accounts quoted by Whittington suggest further study of the ways in which Hollywood sound personnel have legitimised themselves and their changing work practices. Dreams of sonic authorship matched the DIY auteurist sensibilities of a generation of film directors fresh out of US film schools. Walter Murch, who worked with George Lucas and Francis Ford Coppola, coined the term 'sound design' because it marked out a distinct practice and occupation from other sound technicians and held out the promise of more influence over key creative decisions. Ben Burtt, who produced the sonic icons ('sicons') of lightsabres, robot buddies and battleships in Star Wars also figures prominently here, as the prestige of the sound designer grows at the same time as the record producer is hailed as studio auteur. Whittington notes that an increasingly 'cinematic' rock-music culture contributed to the growing audio consciousness of filmgoers and filmmakers through its concept albums, psychedelic imaginaries and spectacles.As well as offering a genealogy of sound design as industrial practice, Whittington contributes to the historical literature on sound technologies in Hollywood. Most of that scholarship has covered the studio system from the late 1920s to the end of the 1950s, listening to the gangster film, the women's film, the musical and film noir. In the New Hollywood, Whittington argues, the idea and development of sound design were intimately associated with the sf genre. In Europe and the US, sf was key to the emergence of a meta-cinema that reflected on film as technology, medium and cultural form. …

Large, sleek, slim, stylish flat screens: Privatized space and the televisual experience

This paper is an analysis of recent print media/magazine advertisements featuring home theatre systems and Plasma as well as LCD televisions in Australia. In their promotion of large new flat television screens, the paper reveals how advertisers highlight the social atomization of space by creating private, isolated cinematic spaces where television viewing is privatized. As a consequence, broadcasting as a collective shared experience is diminished. The focus on the isolated viewer who can personalize and atomize his or her viewing experience privileges a form of privatization (Williams, 1974, 26–27) that stresses the “self-sufficient” home, enabled through a kind of technological mobility. My main argument is that the advertisements signify a privatized individual viewer. Rarely do they suggest that television watching is also a social and collective experience.

Moving sounds enhance the visually-induced self-motion illusion (circular vection) in virtual reality

While rotating visual and auditory stimuli have long been known to elicit self-motion illusions (“circular vection”), audiovisual interactions have hardly been investigated. Here, two experiments investigated whether visually induced circular vection can be enhanced by concurrently rotating auditory cues that match visual landmarks (e.g., a fountain sound). Participants sat behind a curved projection screen displaying rotating panoramic renderings of a market place. Apart from a no-sound condition, headphone-based auditory stimuli consisted of mono sound, ambient sound, or low-/high-spatial resolution auralizations using generic head-related transfer functions (HRTFs). While merely adding nonrotating (mono or ambient) sound showed no effects, moving sound stimuli facilitated both vection and presence in the virtual environment. This spatialization benefit was maximal for a medium (20° × 15°) FOV, reduced for a larger (54° × 45°) FOV and unexpectedly absent for the smallest (10° × 7.5°) FOV. Increasing auralization spatial fidelity (from low, comparable to five-channel home theatre systems, to high, 5° resolution) provided no further benefit, suggesting a ceiling effect. In conclusion, both self-motion perception and presence can benefit from adding moving auditory stimuli. This has important implications both for multimodal cue integration theories and the applied challenge of building affordable yet effective motion simulators.

Audio output adjusting device of home theater system and method thereof

A home theater system, an audio output adjusting device of a home theater system and methods thereof allow a prescribed or three-dimension audio configuration state for at least one prescribed position even when the prescribed location and/or a configuration of the speakers in a home theater system are modified. The device can include a checker (10) for analyzing at least one of volume and delay time of a test audio signal outputted from speakers and providing the analyzed information to a controller (20). The controller can control output level and timing of audio signals subsequently output from the speakers (31-36) based on the analyzed information.

Optimizing the sound pressure levels at low frequency limits of electrodynamic loudspeakers

This paper focuses on reproducible low frequency ranges of electrodynamic loudspeaker drivers. The research findings lead to a guide that allows the optimal driver to be selected at the early stages of the design when the consumer electronic products such as home theater systems, digital TVs or PC speakers are being considered. The suggested frequency ranges are based on the acoustics and estimated from statistical data from 1,473 loudspeaker drivers of various sizes. In particular, the lower frequency limit is discussed together with the peak volume displacement which is closely related to the maximum reproducible sound pressure in a loudspeaker.

Upmixing and Downmixing Two-channel Stereo Audio for Consumer Electronics

In this comprehensive study, algorithms for upmixing, downmixing, and joint up/downmixing are examined and compared. Five upmixing algorithms based on signal decorrelation and reverberation are employed to convert two-channel stereo signals to jive-channel signals. For downmixing, methods ranging from mixing with simple gain adjustment to more sophisticated head related transfer function (HRTF) filtering and crosstalk cancellation system (CCS) are utilized to downmix the center channel and the surround channels into the available two frontal loudspeakers. For situations where only two-channel content and loudspeakers are available, a number of up/down mixing schemes are used to simulate a virtual surround environment. Emphasis of comparison is placed on two consumer electronic products: a 5.1 home theater system and a dual-loudspeaker MP3 handset. The effect of loudspeaker spacing on rendering performance is examined. Listening tests are conducted to compare the processing methods in terms of three levels of subjective indices. The results are processed by using the Multi-Analysis Of VAriance (MANOVA) to justify the statistical significance, followed by a multiple regression analysis to correlate the auditory preference with various timbral and spatial attributes.

BEYOND THE MULTIPLEX: CINEMA, NEW TECHNOLOGIES, AND THE HOME

Book Review| July 01 2007 BEYOND THE MULTIPLEX: CINEMA, NEW TECHNOLOGIES, AND THE HOME BEYOND THE MULTIPLEX: CINEMA, NEW TECHNOLOGIES, AND THE HOME, Barbara Klinger. STEPHEN GROENING STEPHEN GROENING Search for other works by this author on: This Site Google Journal of Film and Video (2007) 59 (2): 56–58. https://doi.org/10.2307/20688560 Cite Icon Cite Share Icon Share Facebook Twitter LinkedIn MailTo Permissions Search Site Citation STEPHEN GROENING; BEYOND THE MULTIPLEX: CINEMA, NEW TECHNOLOGIES, AND THE HOME. Journal of Film and Video 1 January 2007; 59 (2): 56–58. doi: https://doi.org/10.2307/20688560 Download citation file: Zotero Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All Scholarly Publishing CollectiveUniversity of Illinois PressJournal of Film and Video Search Advanced Search The text of this article is only available as a PDF. Copyright © 2007 Board of Trustees of the University of Illinois2007 Article PDF first page preview Close Modal You do not currently have access to this content.

지상파 DMB를 통한 멀티채널 오디오 서비스 검증에 관한 연구

According to the advancement of multimedia compression technologies, high quality multi-media services are easily found in common life. Along with this situation, 5.1-channel audio service also has expanded the application area to home theater system and car theater system and consumer can easily take a chance to experience the feeling of 5.1-channel audio. On the other hand, terrestrial DMB service has been launched in Korea from Dec. 2005 as a handhold multi-media broadcasting service. However, multi-channel audio was not considered due to the insufficiency of bandwidth and the handhold usage. Lately, MPEG is standardizing high efficiency multi-channel audio compression technology for handheld broadcasting service, and several trial for application is introduced in Europe. In this paper, we would like to explain multi-channel audio compression technology, describe the implementation of the verification system for the multi-channel audio service over T-DMB and investigate the possibility of further realization of the service.

All Digital Spread Spectrum Clock Generator for EMI Reduction

An effective solution to control electromagnetic interference in computing appliances such as DVD players or home theater systems is to apply modulation on the system clock. The presence of modulation on the clock reduces the radiated power per unit bandwidth. We present the implementation of a spread spectrum clock generator (SSCG) using strictly digital components. A digital delay line (DDLi) controlled by a small digital circuit is used to increase or decrease the delay on a clock and hence create a modulated output. The DDLi total electrical length is no longer than one period of the 27-MHz reference clock as the digital circuit can adjust to the limited length of the line. The circuit can produce up or down spread by modulating the frequency of the reference with a triangular waveform. The measured peak power reduction is greater than 13 dB for a deviation of about 3% and a frequency modulation of 100 kHz. A real-time digital calibration circuit enables a process and temperature independent operation. The circuit occupies 0.06 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> in a 0.15-mum CMOS process and consumes 7.1 mW

A hybrid approach to rendering multichannel audio, using wave-field synthesis and stereophonic techniques, with virtual microphone control

In the evolution of multichannel audio presentation, a number of formats have emerged including 5.1 surround and wave-field synthesis (WFS). Due to the complexity and number of components required to realize an immersive WFS system, the use in a home theater environment is currently impractical. This study aims to investigate the perceptual advantages of integrating both systems into a hybrid array capable of providing immersive sound for a number of listeners, at a scale that is attainable for the consumer in terms of budget and complexity. In this approach the three front speakers (left, center, and right) are replaced with a linear line array allowing for a better lateral and depth imaging, while increasing the sweet spot. The rendering will be created using Virtual Microphone Control (ViMiC) for both WFS, simulating a line of omnidirectional microphones with ViMiC, and surround sound, which will allows dynamic source movement, speaker positioning, and scalability. The advantage of using this hybrid approach is the application of WFS to home theater systems without facing the complexity of a complete two-dimensional WFS array, while still allowing for an immersive sound presentation. A psychoacoustic evaluation will be presented, as well as measurements of the composed sound field.