Ultra high resolution television (UHDV) prototype
Posted by Sean Byrne on 29 September 2003 - 11:32
Japanese engineers have been testing out a prototype of ultra high definition video (UHDV) which has 16 times greater image resolution than today’s best standard HDTV. UHDV uses 4,000 horizontal scanning lines, which is 4 times that of HDTV and over 6 times that of regular TV PAL broadcasts.
As no existing equipment could handle such as resolution, they had to make a custom built camera, storage and projection system using arrays of existing components in order test a prototype. To even store just 18 minutes of UHDV footage, they had used 16 HDTV recorders (likely a 4 x 4 array) with a capacity of 3.5 terabytes 3 minutes of footage was recorded from the custom made camera mounted to a vehicle and then driven about the streets.
The footage was later projected on a 4 x 7 metre screen for public demonstration and the public were astonished. As the visual effect of the footage travelling down a road was so realistic, some viewers even experienced nausea as a side effect of seeing ultra realistic motion, but not physically feeling the motion. It's like the opposite of seasickness where you can feel movement, but cannot see it while in an enclosed section.
A prototype digital video system producing images of such high quality that the human eye struggles to distinguish them from reality has been developed by Japanese engineers.
The system, called ultra high definition video (UHDV), achieves image resolution 16 times greater than even the most advanced video broadcasting technologies now available.
Its developers at the Japan Broadcasting Corporation (NHK) said the system could be used to provide an ultra realistic 'immersive' viewing experience when, for example, showing sporting events.
UHDV displays images with 4,000 horizontal scanning lines, compared to the 1,000 offered by the current state-of-the-art high definition television (HDTV) technology and just 625 for standard TV broadcasts. When horizontal and vertical scanning are both taken into account a UHDV picture contains 16 times the number of pixels ? individual image components - of HDTV.
NHK, which unveiled details of UHDV for the first time at broadcast technology conference IBC in Amsterdam, said its engineers had to custom-design a video camera, data-storage device and projection system, as no standard broadcasting equipment could cope with their extreme demands.
The camera was built by aligning four 2.5in charge coupled device (CCD) image-capture panels. The projector system uses four liquid crystal-on-silicon panels, two of which process green light while the other two each handle red and blue. These must be aligned to an accuracy of within 0.5 of a pixel - there are 33 million pixels on display - to achieve ultra high definition results.
Recording the massive amounts of data needed to produce UHDV definition also posed a problem for NHK. Its engineers were originally only able to make 34 seconds' worth of recording. They have now built a disc recorder system made up of 16 HDTV recorder units with a capacity of about 3.5 terabytes, allowing them to shoot 18 minutes of UHDV footage.
NHK researcher Dr. Kohji Mitani said the project team had shot a three-minute demonstration video by attaching the camera to the front of a vehicle and driving it around the streets.
The footage was then shown to members of the public on a 4x7m wide-angle screen provoking, according to Mitani, gasps of astonishment. Some viewers even experienced nausea because of the ultra realistic visual effect of speed without the usual physical sensation of movement.
Mitani said the system was still at a basic stage of development, but he claimed it had proved that image qualities so realistic that they approximated to actually being at the recorded event were possible.
NHK will now attempt to reduce the size of the camera and look at the possibility of developing transmission systems that could broadcast UHDV footage.
Dr. Nicolas Lodge of UK broadcast technology specialist Pro-Vision Communications, who chaired the IBC session at which UHDV was presented, said the NHK work was 'amazing stuff. They are on the way to creating an experience that mimics actually being there. It is an exciting area of research'.
