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David Javelosa

Copyright © 2003 - 2014 David Javelosa unless otherwise stated.

week 14 - sound & music for interactive environments

sound & music for interactive environments

SoftEffects: Audio Plug-ins used for real-time playback

XG is known as Yamaha's extension to the General Midi standard as a computer music solution and a tool for music development in technology based entertainment. Besides the expanded instrument definitions and expanded performance control of synthesizer based music data, this defines a number of effects as part of its audio palette.

These effects typically include: Reverb, Delay, Wah-wah, Auto Pan, Distortion, Phaser, EQ, etc. and have been taken from technology developed for higher-end, pro-audio studio products. Featuring this collection of effects as part of this specification has ensured a high-quality, expressive playback format in a low-bandwidth solution. Expanding beyond the effects included in XG is a stand-alone version of this effect suite for two current game platforms and as a production plug-in.

The value of using the same technology in both the development phase and on the playback system is obvious: consistent sound quality from creation to target. The added value is in the interactivity. Being able to audition the various effect parameters is important for interactive playback on the target side. The game industry plans to have a developer friendly interface/tool for the effects on the platform side, helping the game audio developer to easily implement the effects. Currently there is a stand-alone demo of the effects for Windows that will play a multi-track demonstration using a number of different effects on different channels. The parameter control screen allows real-time editing of the effects during playback. The performance is only limited by the power of the host machine, and how many channels are being used at once.

The format for these effects plug-ins is Microsoft's DirectX. This allows developers to use SoftEffects with most of the leading audio development applications and hybrid Midi-Digital Audio programs. The effects are currently being converted from the original DirectX format (DirectShow) to DMO (DirectMediaObjects) to allow for processing audio material from different sources (i.e. software synthesizer, wave files, streaming ). This also enables compatibility with the DirectX 8 version of DirectMusic. This environment will control the SoftEffects through the iMedia params of DirectMusic Producer. It may also be possible to control effect parameters through Midi and other formats in the future.

Because of these DirectX origins, the obvious platform support for SoftEffects will be for PC games based on DirectMusic and DirectSound. Having the development environment the same as the delivery platform has always been an advantage for PC game development.

SoftEffects is also being developed for Sony's Playstation 2. The same effect technology from the XG specification is being modified to run on the PS2 hardware as a realtime audio middleware. Also being developed is a user-interface audio tool that will run on the PS2 development system. Because of the consistency in quality and parameter controls, this will contribute significantly to the porting of games between platforms, or the simultaneous development of a title for both PC and PS2. Coupled with the DirectX plug-in version, SoftEffects stand to be a major leap in game audio development, continuing quality to the world of interactive entertainment.

Quality of Downloadable Samples In Interactive Media

In the fields of interactive entertainment and interactive music production for games, these advances are a major leap in performance, quality and data resource management. Optimizing the size and use of musical and audio data is a major concern in producing today's interactive world. From an audio perspective, technology limitations and manufacturing costs restrict the use of large, high-bandwidth media, and the dynamic nature of the gaming experience insists on a context specific, dynamic, and adaptive musical experience.

With the development of the DLS (downloadable sounds) standard, the quality of interactive music playback is becoming standardized at a level comparable to that of traditional high-fidelity media. This standardized quality is assured independent of hardware support. By including only specific downloadable sample, a file can maintain the playback consistency of high-band audio while optimizing its size with Midi information.

Microsoft's DirectMusic technology (including DLS) takes the task of optimizing Midi and digital audio data yet another step further. By breaking down musical components of a composition into segments of Midi data, DirectMusic can generate performances of the music in seemingly infinite variations, affecting elements of key change, "personality", instrumentation, rhythmic density, and melodic sequence. A well crafted DirectMusic file can provide extremely long performances of non-repeating, high-quality music from a finite number of Midi and audio elements. Adding controls generated from user input allows real-time musical variation in a coordinated game experience.

The concepts of making music interactive stem from the conceptual beginnings of video and computer games, and other variations of interactive entertainment. In the most common applications of interactive music, the musical activity is drawn from a bank of common musical elements ranging from samples of phrases, instrument samples, segments of Midi data, or individual note information.

Viewing a piece of music from its compositional segments, the advantages of this form of music are two-fold: saving data space AND providing a non-linear musical experience. A file size of 200 kb could provide much more than a minute of linear music. In effect, these are the basic principles behind the DirectMusic architecture. The added bonus of DLS is that a "soft" synthesizer playing custom samples insures a quality playback experience.

The development of Microsoft's DirectMusic architecture has created a standard format for high-quality, low-bandwidth, interactive music. Having this system as a part of the Windows OS delivers the ability for any game to have the best musical experience available from limited media assets. The wide-spread support of DLS insures this quality level across a wide range of hardware and software combinations, essentially creating a level playing field for computer music playback.


- Import video as Quicktime Movie
- Import audio track from video as "other movie"
- Create parallel tracks for sound effects, voice over and musical score replacement
- Edit
- Bounce to movie as mixed sound track


next - Week 15 - Exam Review - Pro Tools feature review
Week 16
- Final Exam - FINAL pro tools project due:

Develop a sound design for the provided video clip that should contain the following elements :

  • sound effects
  • music, looping phrase or bed track
  • voice over
  • transitions
  • fades
  • 2 or more elements spotted to picture

Grades at the "A" level will require more than these minimums. The more original the design, the better the grade.

Additional possibilities include:

  • musical arrangement with track looping
  • voice over cut to the measure
  • voice over or dialogue matched to character events (dubbed)

Copyright © 2003-2014 David Javelosa