Work in the video coding space progressed,
following meetings taking place in Geneva in
April.
Also, the beginning of the month saw the Japan launch of
a new mobile terrestrial digital audio/video broadcasting service using H.264
and called "1seg". The video compression standard (full
name ITU-T Rec. H.264 or MPEG-4 pt.10/ AVC) jointly developed by ITU-T SG16 and
the ISO/IEC Moving Picture Experts Group (MPEG) is now being deployed in products from companies
including Apple, Sony, BT, France Telecom, Intel, Motorola, Nokia, Polycom,
Samsung, Tandberg and Toshiba and in services such as over-the-air broadcast
television, the new HD DVD and Blu Ray disc formats, and a large number of
deployments of direct-broadcast satellite-based television services.
In Geneva,
a new Recommendation was consented that will allow the use of a ‘back channel’
to convey the level of loss or corruption in video messages and if necessary
apply measures to compensate for that. So, for example, at the content delivery
end, an encoder, upon determining that a message is not getting through properly,
may decide to reduce the message to its bare essentials resulting in a
lower fidelity for the end user. Alternatively, the encoder
and decoder can deploy intelligent recovery mechanisms. This will better
support Recommendation H.264’s use in environments that may be more susceptible
to error, for example in mobile telephony and IP-based video conferencing.
The new Recommendation has been drafted in such
a way that it can be applied to existing (e.g. H.262, H.263, H,264) and
future video coding standards.
The work took place during co-located meetings
of the Joint Video Team (JVT) and ITU-T Study Group 16, home of media coding
work in the ITU. Over 90 documents were considered by the JVT group, which
is the ITU-T and ISO/IEC joint project to enhance standard video coding
performance, and is home to H.264/AVC.
An amendment to H.264 added support of
new extended-gamut colour spaces, which are recently-specified
enhanced methods of measuring and representing the brightness and color of the
objects in video pictures. Also, in relation to H.264, work continued
on developing new profiles supporting H.264’s use in high-end studio
applications that use the 4:4:4 color sampling system and on developing
scalable video coding (SVC) extensions of the standard as well.