Automatic Digital Video Picture Quality Monitoring Technique

The NHK Science & Technical Research laboratories, in a joint project with the KDDI R&D Laboratories, has begun research on a technology for monitoring the picture quality of digitally compressed video data in real-time.
In digital broadcasting, the video signal is digitally compressed for transmission. Although most of this compressed signal maintains good picture quality, in some cases the picture quality may deteriorate, depending on the image contents. For this reason, picture quality monitoring for digital broadcasting has become an extremely important subject. Once this newly developed technology is put into practical use, automatic monitoring of digital video quality will be realized. This will also enable picture quality monitoring at any of the transmission and video processing stages that utilize digital compression.
While the degree of quality degradation can be evaluated by comparing pre- and post-compression video signals, in the case of broadcasting it is difficult to obtain original pre-compression video signals for comparison. This emphasizes the necessity of picture quality monitoring technology that can estimate the degree of picture quality degradation based only on already digitally compressed video signals. The development of this picture quality monitoring technique makes it possible to manage picture quality precisely throughout the production process, right up to actual broadcasting. It will be utilized for digital broadcasting quality control.
(Eisuke Nakasu, Multimedia Services)




Telecom Asia
"Telecom Asia 2000" was held in Hong Kong, from December 4 to 9, 2000. This is a regional event organized by the ITU, consisting of exhibitions of the latest technologies by information communication companies and device manufacturers, and a forum where policies and business trends are presented.
Director-general YAMADA of the STRL was a guest speaker during the event, speaking on the theme: "Approaches to Digital Broadcasting in Japan," introducing trends in digital BS and terrestrial broadcasting in Japan, as well as the interactive services provided by digital BS broadcasting. The event was held right after the launch of digital BS broadcasting in Japan and generated a high level of interest among participants, demonstrating to the world the appeal of Japan's digital BS broadcasting.
(Hideki Suganami, Planning & Coordination)


R&D on the Next Generation Mobile Satellite Communications/Broadcasting System

The Advanced Space Communications Research Laboratory (ASC) was established in 1994 with the aim of performing research and development on the next generation S-band (2.5-2.6GHz) mobile satellite communications/broadcasting system using a geostationary satellite. Its R&D theme covers technological development, including a large deployable antenna, high-power transponder, and a handheld terminal, as well as the analysis and evaluation of these systems.
Two engineers were on loan from NHK to the ASC, and engaged in projects concerning a 2.5-2.6GHz-band digital satellite sound broadcasting system and handheld terminals for mobile communications. During the research period, the expected purposes were achieved in the development of new technologies in step with the progress of digital technology.
The ASC completed its 7-year R&D period at the end of February of this year. Individual components developed at the ASC are scheduled to be installed on Engineering Test Satellite VIII to be launched in fiscal 2003. It is expected that the ASC's accomplishments will prove their value during the scheduled orbital tests.
(Hideo Mitsumoto, ex-Manager of System Research of Department, ASC)


Development of Prototype 2000 Scanning Line Ultrahigh Definition Color Camera
The NHK Science & Technical Research Laboratories constructed an experimental ultrahigh definition color camera with twice the number of scanning lines as that of the Hi-Vision (HDTV) system. NHK has been promoting a "super reality broadcasting system" with the ultimate goal of 4,000 scanning lines. This prototype system was developed with that project goal in view.
The prototype camera is a 2,250 scanning line, 60 frame per second progressive-scanning system. It provides a quantity of information eight times greater than the conventional HDTV system. An 8 million pixel CCD was also developed to be used as an imager for the camera*. With the newly developed CCD, a low clock frequency is maintained by dividing the screen into 16 parts, and taking out individual video signals for each portion.
Note*: Joint development with Dalsa Co., Canada.

Table: Prototype camera specification
Total horizontal pixels 4,400 pixels/line
Total lines 2,250
Valid pixels Approx. 8 million
Aspect ratio 16:9
Frame frequency 60 frames/second
Scanning system Progressive scanning
Imaging system RGB 3 CCDS

(Masayuki Sugawara, Three-Dimensional Audio-visual Systems)



HARP Imaging Tube Exhibited at RSNA

At the end of November 2000, at the exhibition of the Radiological Society of North America (RSNA), I spoke of the outstanding performance of the ultrahigh-sensitivity HARP imaging tube and its use in the medical field.
Upon seeing presentation of an introductory video on the HARP imaging device and an actual video demonstration using an ultrahigh-sensitivity HARP camera, a number of major medical equipment manufacturers expressed keen interest in the system, seeing its suitability for use in portal imaging (for the irradiation monitor of the cancer radiation therapy machine).
HARP photoconductive film, with its ultrahigh-sensitivity and resolution, even has the potential to shoot a clear real-time image of a microscopic grain of calcium, as observed in the first stage of breast cancer. Future application of this HARP technology to the early detection and diagnosis of breast cancer has already drawn much attention.
(Kenkichi Tanioka, Advanced Imaging Devices)






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