SANTA CLARA, CALIF. –
Zaxel has developed 4K RGB H.264 and 4K RAW
H.264 codecs that it will demo at the NAB Show, according to its principal, Dr.
Nori Suzuki. Dr. Suzuki reasoned that much more 4K content is available in RGB
and RAW formats than HD or SD because most high-end 4K video cameras capture
video as RAW or RGB 444 formats. All the 4K CG content for animation and
engineering use are also in RGB 444 formats, he said.
Dr. Suzuki went on to say that intraframe compression used in post production
and digital cinema such as ProRes and JPEG 2000 can directly compress RGB 444. Therefore,
huge video quality degradation associated with color space conversion and
chroma subsampling to YUV 422 or YUV 420 can be avoided.
However, for distribution purposes, a higher compression ratio of interframe
compression is required, since the standard interframe compression such as MPEG
and H.264 can handle only YUV 422 or YUV 420, he said. This introduces
subsampling artifacts such as jaggy edges in addition to other compression
Dr. Suzuki said Zaxel’s 4K RGB H.264 directly compresses uncompressed RGB 444
video into H.264 formats, thus avoiding the subsampling artifacts such as jaggy
edges. RAW H.264 also directly compressed uncompressed RAW video into H.264
formats without color-space conversion. He said RGB H.264 and RAW H.264 are
ideal formats for eCinema servers and home theater players, since projectors
and displays are natively RGB 444 output devices and can eliminate another
Zaxel’s 4K RGB H.264 and 4K RAW H.264 decompression runs in real time on PC
without hardware accelerator, Dr. Suzuki said
Zaxel also has released Zaxtar 5, which can play back 4K 10-bit 60p content and
can directly play back sequences of DPX files and TIFF files. Zaxel will
demonstrate Zaxtar 5 by driving Sony VPL-GT100 projector through two DisplayPorts.
Sony VPL-GT100 is capable of projecting 4K 10-bit 60p. Zaxtar 5 can also be
upgraded to stream 4.8 GBps from the SSD array so that a dual stream of 4K
10-bit 60p can be played back. This dual-stream version can drive two Sony
VPL-GT100 for stereo 3D, 8Kx2K projection with edge blending, or dual brightness.
Dr. Suzuki demonstrated live, uncompressed 4K projection on a four-foot screen
in 60p at last year’s NAB
. This year, he will be in booth No. N1338.