Hardware MPEG2 Encoding in a Notebook?
The MPEG-2 R-Engine forms the most interesting aspect of the Sony VAIO PCG-C1MT. The Sony VAIO PCG-C1MT is the first notebook to feature a hardware MPEG2 encoding chip. The chip enables the VAIO to capture and encode movies in real-time via an analog source. Of course, with a built-in FireWire port, capturing videos through a digital video (DV) source is possible too.
When asked why they opted to use hardware MPEG2 encoding, Sohei Taki, the engineer in charge of image-related hardware said that since MPEG2 is the standard format for DVD video and BS Hi-Vision, it would seem logical to adopt this format. Previous VAIO C1s have incorporated Motion JPEG hardware encoders since the C1XE but the format lacks standard. Compatibility was an issue with Motion JPEG as other PCs would not play the format without the proper codec. According to Sohei Taki, real-time encoding (compression) on a PC is still a problem today. Even when you use a 1GHz CPU, capturing video in real-time without losing frames still poses a challenge. "This is why we opted for LSI based encoding. Since a chip handles the processing, we could achieve 30 fps at a high picture quality of 640x480 pixels, all powered from the battery," said Sohei Taki.
Indeed it took Sony a while to integrate a real-time LSI into a mobile PC. Previous generation LSI encoders were too large for the notebook. However, they recently managed to develop an LSI that fits the requirements of the VAIO C1. The new MPEG2 R-Engine is only a mere 14mm as compared to the conventional Motion JPEG encoder which is four times the size of this new chip.
Incorporating the MPEG2 encoder was not an easy task. According to Taki, the effects of noise against the analog circuit due to the A/V input terminal had to be carefully considered and worked around. The incorporation of DDR-SDRAM made it harder as they had to adopt drastic design changes. "Honestly, I was gladly surprised when the base featuring all functions was completed," said Taki.
Small, slim and stylish - that's the VAIO PCG-C1MT.