Image Processing Reference
In-Depth Information
MPEG-2. These licensing terms have eased somewhat but there are some significant risk
factors with licenses that you must assess. These are discussed in Chapter 18.
At the point where the MPEG-4 standard was ratified and beginning to get some
interest, the licensing of patents suddenly became a hot topic. Broadcasters simply were
unwilling to pay fees based on per stream, per user, or per minute of programming. They
are well used to purchasing expensive equipment and software, with any licensing fees
being recouped via a premium that is paid once when the technology is purchased. The
European Broadcasting Union (EBU) stated in the fall of 2003 that it did not expect any
broadcaster to find usage-based terms attractive.
The debate continued until the summer of 2004, and this gave a significant commer-
cial advantage to proprietary codec makers. By making their proprietary licensing terms
slightly more attractive than the H.264 terms, they won some converts.
A reasonable compromise seems to have been reached with encoder manufacturers
paying a levy and content owners paying a small premium per copy that is distributed
commercially. Charging on a per-copy-produced basis must be controlled to avoid hurting
nonprofit organizations and small niche producers. As a result, nonprofit organizations
and broadcasters are exempt from fees—at least for now.
The MPEG-4 part 2 codec is the one being cited when Windows Media Series 9 (WM9)
and MPEG-4 are compared for performance and quality vs. bit rate and efficiency in mar-
keting presentations. It is true that WM9 is superior to the MPEG-2 codec. However, when
comparing WM9 with H.264, the contest is far more equal. Be very careful that the MPEG-
4 codec being referred to in discussions is the one you intend to be talking about—espe-
cially when comparing performance with other codecs. The MPEG-4 part 2 and MPEG-4
part 10 codecs are completely different. Here are the main attributes of the MPEG-4 part
2 codec:
Good quality
Likely to be superseded by the H.264 codec
Good file size at low bit rates
Files get too large at high data rates
Compatible across many player platforms, such as Real Networks and QuickTime
(with some constraints)
A useful general-purpose codec
Sorensen version delivers marginally better quality but less-efficient compression
3ivX is a good implementation available for Windows.
Now that the H.264 (MPEG-4 part 10) standard is available, regrettably the MPEG-4
part 2 codec has largely been superseded. It didn't offer sufficient advantage over MPEG-2,
which has caught up with it in the latest implementations. H.264 goes significantly
beyond MPEG-4 part 2 with its compression efficiency and lacks only the alpha-coded
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