Information Technology Reference
In-Depth Information
Every New Year's Eve, a popular music show is broadcast from the NHK Hall
in Tokyo. On December 31, 2006, NHK conducted an experiment on the live relay
broadcast from Tokyo to Osaka for public viewing of the music program. This ex-
perimental transmission was carried out over 500 km and for about 5 hours. The
transmitted program was screened at a special theatre in Osaka. The 22.2 mul-
tichannel sound was uncompressed. The video and audio signals were transmitted
as multiple IP streams, and the difference of the delay between the IP streams was
negligible enough to be ignored. The total TS bit-rate was 640 Mbps, and the total
system delay was approximately 700 ms and was dominated by the codec delay.
Forward error correction (FEC) was not used, but there was no packet loss for the
duration of the live event. This experiment verified that long distance SHV trans-
mission is feasible. The setup and appearance of the experiment are shown in
Figure 11.
In September 2008, the first international SHV live transmission was held from
London to Amsterdam where IBC 2008 was opened [12]. A camera head and the
microphones of the SHV system were placed on top of London City Hall. The
coded SHV signal as an IP packet stream was carried via an international fiber-
optic undersea cable link to Amsterdam. A diagram of the transmission from Lon-
don to Amsterdam is shown in Figure 12. To demonstrate the live nature of the
link, the scenario was to emulate live news reports from London to Amsterdam
with two-way interaction between a reporter at City Hall and a presenter in the
SHV theatre in Amsterdam. The appearances of the demonstration are shown in
Figure 13. The received picture quality was excellent, enabling the fine details of
the scene to be visible, and the surround sound quality was also extremely high.
No bit errors were detected on the link over the five days of the experiment. This
demonstration showed the possibility of live SHV content being relayed from
virtually anywhere in the future.
Fig. 12
IP transmission from London to Amsterdam
