HDMI 1.3 Speeds xvYCC Adoption in Camcorders
Sony Corp of Japan has released a camcorder (Fig 1) capable of shooting using the extended-gamut YCC (xvYCC) color space standard, considerably wider than conventional camcorders. The xvYCC color space is already supported by imaging equipment such as a portable viewer from Seiko Epson Corp of Japan and a liquid crystal display TV from Sony Corp of Japan, but there has been very little video content with xvYCC color to utilize the full potential of these display devices. The new camcorder is effectively the first consumer product capable of producing xvYCC video content.
Sony said it adopted xvYCC in its camcorder so that it could express deep greens, brilliant pinks and other colors unobtainable from International Telecommunication Union Radiocommunication Sector (ITU-R) BT.709 (equivalent to sRGB in still pictures), which is the most commonly used color space (Fig 2). A source at Sony commented, "We can express the colors of the natural world more faithfully than ever." To promote consumer recognition of the xvYCC standard, Sony has proposed to the electronics industry that it is called "x.v.Color" and has already begun using the new name in the new camcorder.
"Our first concern in commercialization was ensuring compatibility," said a source at Sony. xvYCC is defined as an extension to existing color space, so that color information expressed as per ITU-R BT.709 will display the same under xvYCC. When xvYCC video content is played back using a video interface or equipment not designed for xvYCC, it was impossible to rule out unexpected display results, such as no picture at all. To avoid this type of problem, Sony assigned priority to verifying that compatibility was assured. It connected the new camcorder to a range of TVs which did not support xvYCC, and displayed imagery. The results confirmed that no problem exists, said Sony.
The camcorder is the first to come with a High Definition Multimedia Interface (HDMI) 1.3 interface in addition to the component video and S video output interfaces. HDMI 1.3 is used to notify the TV or other equipment that the video signal is xvYCC-compliant, using metadata. Display devices supporting HDMI 1.3 can check the metadata to facilitate xvYCC color space-enabled display. Making it possible to view xvYCC via HDMI 1.2 or existing analog interfaces incapable of making decisions without analyzing the signal content is likely to be fairly complex.
by Chikashi Horikiri