Toshiba tailors MPEG-4 interface for specific baseband chips

Toshiba tailors MPEG-4 interface for specific baseband chips
By Junko Yoshida, EE Times
October 31, 2001 (1:02 p.m. EST)
URL: http://www.eetimes.com/story/OEG20011030S0044

SAN MATEO, Calif. — Sounding a note of caution for system integrators looking to add wireless video features to mobile handsets, Toshiba America Electronic Components Inc. (San Jose, Calif.) said its MPEG-4 decoder and encoder/decoder ICs, both sampling now, are tailored to specifically interface with Qualcomm Inc.'s MSM3300, a leading baseband processor for cdmaOne handsets.

Toshiba is also sampling the MPEG-4 encoder with minor firmware changes that allow it to interface with Infineon Technologies' baseband processor for the GSM market in Europe.

Designers who have selected a different baseband processor for their handset may face the unpleasant surprise of adding another chip of glue logic or of finding their handset's performance compromised, said Andrew Burt, wireless market development director at Toshiba.

Toshiba's single-chip MPEG-4 decoder, priced at $35 in sample quantities, integrates three 16-bit MIPS cores, 4 megabits of em bedded DRAM, an on-chip system bus, host interface and analog components for connecting to microphones, loudspeakers and such. The MPEG-4 chip consumes 50 milliwatts and can guarantee the delivery of QCIF-standard 176 by 144-pixel video at 15 frames per second, Burt said.

Toshiba's separate MPEG-4 encoder/decoder chip, based on the same architecture, consumes 80 milliwatts and is priced at $55 in sample quantities.

"Our chips maintain the direct interface with Qualcomm's chip, both on the physical/electrical and firmware levels," Burt said.

Although its relationships with Qualcomm and Infineon are not exclusive, Burt said Toshiba is the only partner of Infineon and Qualcomm supplying hardware-based MPEG-4 solutions optimized for the partners' respective communication processors. "We are pursuing joint customers through joint marketing," he said.

Hampered performance

Without a tightly designed interface between a handset's baseband processor and multimedia co-processor, "an MP EG-4 core that claims to offer 30 frames per second in CIF resolution could result in a handset capable of producing only eight frames per second in QCIF," said John Daniels, program manager of the Imaging Internet Application Group at Texas Instruments Inc.

TI, a leading provider of baseband communication processors, is sampling the TMS320DSC24 digital-signal processor as a multimedia co-processor. The chip interfaces directly with TI's baseband communication processor. The DSP performs real-time media processing and an ARM7TDMI processor performs system control functions. The DSC24 DSP architecture will provide a future road map to TI's OMAP architecture, Daniels said. Not yet in volume production, the OMAP chip is designed to combine baseband processing and multimedia processing in one chip to support QCIF video at 15 frames/s.

Toshiba engineers worked closely with Qualcomm to make sure the companies' chips talked well together, Burt said.

On the firmware level, Toshiba engineers added firmwar e to the well-established protocol stack of the Qualcomm baseband processor. "Most handset vendors do not want to switch code or processors," said Burt. "We made sure that our MPEG-4 decoder optimizes the system OEM's handset design rather than compromises it."

Noting that the OMAP platform will help TI remain a formidable competitor, Burt said Toshiba believes its technology has "advantages that enable an efficient low-power design. Besides, OMAP will not replace Qualcomm's baseband chips," he said.