Addressing a major weakness its plan to build its WebM video technology into the Web, Google yesterday released a version of its VP8 video encoder and decoder designed to be baked into hardware.
The hardware implementation of VP8 is called H1 and now Anthill, said Aki Kuusela, engineering manager of the WebM Project, in a blog post. It comes in the form of RTL, or Register Transfer Language, a very low-level description close to how processors actually perform their instructions, and it's available royalty free.
"The H1 hardware encoder can produce good quality with very low power consumption using almost no clock cycles from the CPU," Kuusela said. "The H1 encoder offloads the entire VP8 video encoding process from the host CPU to a separate accelerator block on the [processor]. It significantly reduces power consumption and enables encoding of 1080p resolution video at full 30 frames per second, or 720p at 60 FPS. Without a hardware accelerator like the H1, modern multi-core mobile devices can only encode video at around VGA 25 FPS, and are not able to do much else while doing that."
VP8 competes chiefly with a codec called H.264, also known as AVC and or MPEG-4 Part 10. It's widely supported in everything from videocameras to personal computer operating systems, but it's encumbered by patent licensing requirements. With VP8 and WebM, Google hopes to lower the barriers for digital video, especially on the Web.
Royalty-free VP8 is be cheaper to use than H.264, but VP8 may not offer a royalty-free ride forever, though. That's because MPEG LA, the group that licenses the pool of H.264 patents, is seeking patents that patent owners believe VP8 requires. That's a necessary step in preparing for a VP8 patent pool, an idea Google doesn't like one bit.
One big advantage H.264 has is hardware support that makes encoding and decoding faster and less of a drain on mobile devices' precious battery power. Thus, Google is trying to encourage hardware support, and it's made some successes with Texas Instruments and Rockchip.
As is common for hardware codecs, Anthill doesn't match the quality of Bali, the latest software version of the open-source VP8 codec, Kuusela said.
"In the next release, we are planning to narrow the quality gap between the libvpx 'Best' mode and the hardware implementation, while cutting down the required power even further. The next release is planned to be out in early Q2," he said, perhaps a sign that Google hopes to keep the hardware codecs on the same rapid quarterly release track as the software codec.
Google faces many challenges in spreading VP8 far and wide, but it's won over the makers of the Firefox and Opera browsers. And today, Opera announced it's begun supporting a related technology for still image compression called WebP.