Archives for November 1996

Cupertino, CA. With uncompressed audio over the net weighing in at upwards of 500 kbits/second, and the most heavily compressed speech files moving at around 8 kbits/second, Apple Computer figures there’s room for a new bandwidth-saving approach to moving speech across the web.

Apple engineers think the answer may be SPIDI (Streamed Phoneme Intonation Description Interchange), which couples a MIDI-like data description protocol with Apple’s speech synthesis software technology. Their goal is to provide natural, human-like speech at a very low bandwidth for interactive multimedia distribution.

Rather than encoding audio data in terms of digital samples, SPIDI represents speech as a sequence of basic sound units, or phonemes, combined with information about the rhythm and inflection of these sounds. The result is a form of synthetic speech which captures the emotion and emphasis used by human speakers, but which takes up only about 0.8 K bits per second of transmission bandwidth.

Creation of data in the SPIDI format requires a special authoring tool which uses speech recognition to extract vocal inflections from recorded human speech. SPIDI’s inflected data is played back using Apple’s existing synthetic voices (PlainTalk system software).

The SPIDI team is developing cross-platform player components that will be integrated into the QuickTime Media Layer (QTML) architecture. If they get the job done, it will mean that spoken-word audio can be delivered over the Internet without disruption even in low-bandwidth settings. The technology is also said to address the media authoring problem of maintaining lip synch.

Consumer audio trend setter Altec Lansing Technologies is making a hard pitch to capture “mind share” at the Fall’96 COMDEX computing technology exhibition this week. Altec’s focus is on the audio side of the new media convergence that is one of the big movements afoot at the show, which continues throughout the week in Las Vegas.

Convergence in this context means the combination of computing, multimedia, communications, networking, and home appliance technologies, to create new possibilities and impact in home entertainment and leisure activities.

Altec is offering its spin on new media technology with a multimedia theater presentation called “Sound Matters,” at its booth at The Sands Convention Center. Visitors are invited to explore a number of futuristic interactive computer systems demonstrating DVD-Audio, Dolby Digital Surround™, Internet Audio, and audio connectivity through Universal Serial Bus (USB), Firewire (IEEE-1394 protocol), and RF digital wireless technologies.

“We are announcing nine specific technology initiatives designed to provide advanced audio for emerging technologies,” says Edward Anchel, Altec’s President and CEO. “As a result of these initiatives, computer users will enjoy better quality audio than they have ever heard before because of the array of new technologies and products we will deliver to the computer market.”

A key introduction is a PC speaker system that Altec says will be the market’s first USB audio peripheral. Universal System Bus changes the computer audio environment by integrating speaker system functions with the host PC’s internal audio circuitry, allowing direct digital audio streaming to the speakers.

Altec’s first USB speaker system will include proprietary firmware and software, along with an Intel 80930AE chip. The software will function as a user-friendly control interface for the PC audio environment. The system will support multichannel sound streaming that will have applications for communications and video conferencing, as well as for music and gaming audio.

Altec Lansing has also announced that it will develop multichannel direct streaming audio to its speaker systems via the even speedier and higher-bandwidth “Firewire” protocol, also known as IEEE-1394.

Another of Altec’s new initiatives showcased at COMDEX demonstrates discrete multichannel audio delivered by DVD (Digital Versatile Disc). The demonstration focuses on Dolby® Digital Surround (AC3), encoded as six discrete channels, and streamed as compressed digital data to Altec’s USB speaker system. Altec will implement a system of this kind for home theatre applications.

The third key area of Altec Lansing’s COMDEX roll-out introduces high-quality wireless audio transmission for use with computers and home theater systems. The technology involves proprietary compression algorithms and modulation techniques to enable the delivery of audio via spread-spectrum digital RF transmission.