Realtime encoding in software? You get what you pay for.....................................
emediaweekly.com
Codec does real-time MPEG
By Kelly Ryer
The heavy compression of MPEG-2 video encoding usually requires specialized hardware, keeping it out of the reach of mainstream users. Ligos Technology, however, is working on inexpensive, software-only codecs that could make it possible for users to generate high-resolution MPEG-2 video in real time on ordinary Windows PCs.
Due to ship later this quarter to OEM licensees, the GoMotion MPEG-2 codec will be able to perform real-time MPEG-2 encoding and can be used with a third-party video-capture card. Resolution depends on processor speed: Ligos said it has demonstrated real-time encoding of 352-by-240-pixel video on a 266-MHz Pentium II, and said forthcoming Intel chips will allow real-time processing of D1-resolution video.
GoMotion's video quality is "equal to or better than many hardware boards," said analyst Richard Doherty, director of research at the Envisioneering Group of Seaford, N.Y. "Soon, notebook computers will be able to do it in real time. We'll have laptop solutions for doing Webcasts or DVD authoring," he said.
Other analysts disagreed. "At the MPEG-2 level, quality is still better on the hardware side: You tend to get what you pay for," said Norbin Leong, research analyst at Frost & Sullivan Inc. of Mountain View, Calif. "Real-time encoding can be fairly problematic. Software is easier to upgrade in terms of speed and quality, but you still need a really fast CPU."
Because the codec does not require hardware, it will be cheaper to produce than competing chip-based codecs, Ligos said. OEM pricing has not been announced, but according to Court Shannon, Ligos senior vice president of marketing, it should be at least 10 times cheaper than a hardware codec with similar performance. Shannon compared GoMotion to hardware offerings from C-Cube (see 09.21.98, page 19).
Ligos said a proprietary Lightspeed motion estimation algorithm is at the heart of its codecs. MPEG compression represents the differences between blocks of pixels over time as motion vectors, and motion estimation lets the encoder predict which blocks will change.
Ligos also shipped Version 2.5 of its $179.95 LSX-MPEG software encoder last week. Available for download from Ligos' Web site, it encodes MPEG-1 and MPEG-2 video on Windows 95 or NT PCs and can also work as a transcoder, converting AVI files to MPEG. Version 2.5 of LSX-MPEG can write to VideoCD, allowing users to save video on a CD and play it back with standard utilities. Source-frame deinterlacing, median and low-pass filters, and batch-processing have also been added.
Ligos said it plans to ship a Motion-JPEG-to-MPEG encoder within 30 days.
Ligos Technology of San Francisco can be reached at (415) 437-6137 or (888) 464-8765; ligos.com.
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