Cryptography Reference
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including television broadcasting, video-conferencing, digital storage media,
Internet streaming, and wireless communication. It started as H.26L project
in 1997 by VCEG, with the aim to define a new video coding standard that
would have improved coding e ciency of 50% bit rate reduction compared to
any previous standards, simple syntax specification, simple and clean solutions
without excessive quantity of optional features or profile configurations, as
well as network friendliness. In July 2000 MPEG issued new call for proposals
and VCEG proposed H.26L to this call. Among all the proposals submitted to
MPEG, H.26L achieved the best performance. Therefore in Dec. 2001, MPEG
and VCEG formed a joint video team (JVT), and H.26L project became
the JVT project. After that the new video coding standard was renamed
as H.264 under ITU-T and MPEG-4 Part 10 or MPEG-4 Advanced Video
Coding (AVC) under MPEG umbrella.
H.264/AVC contains a rich set of video coding tools that are organized
into different profiles. The original three profiles were defined in the H.264
specification that was completed in May of 2003: the Baseline Profile (BP),
the Extended Profile (XP) and the Main Profile (MP). For applications such
as high-resolution entertainment-quality video, content-contribution, studio
editing and post-processing, it was necessary to develop some extensions of
the tool set for professional video applications. This effort has resulted in a
new set of extensions which are named the .fidelity range extensions (FRExt).
These extensions include four new profiles: the High Profile (HP), the High
10 Profile (Hi10P), the High 4:2:2 Profile (H422P), and the High 4:4:4 Profile
(H444P).
H.264/AVC represents a major step forward in the development of video
coding standards. It typically outperforms prior standards by a factor of two
or more, particularly in comparison to H.262/MPEG-2 and H.263++. This
improvement enables new applications and business opportunities to be de-
veloped. However the improvement in coding e ciency is at the cost of coding
complexity, which is believed to be 35 times more complex than any of its
predecessors. However the phenomenon of Moores Law makes this problem
less important. Furthermore, H.264 is a collaboratively designed open stan-
dard with the aim of very small licensing cost. This will help to create a
competitive market, keeping prices down and ensuring that products made
by a wide variety of different manufacturers will be fully compatible with
each other.
Compared to the previous standards, H.264/MPEG-4 AVC is not a fun-
damentally different method, but rather a significant refinement of well-
established methods. Following list some new techniques that H.264/AVC
has implemented,
• spatial prediction in Intra coding with two block size of 1616 and 44
• adaptive block size motion compensation with variable block size of 44,
48, 84, 88, 816, 168and1616
• 44 integer transformation
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