MNG (pronounced ``ming''), is short for Multiple-image Network Graphics, as one
might gather from the title of this page. Designed with the same modular
philosophy as PNG and by many of the same people, MNG is intended to provide a
home for all of the multi-image capabilities that have no place in PNG.
Although the idea of MNG has been around almost as long as PNG has, serious
design discussions didn't begin until May 1996, and even then there was
considerable debate over whether to make MNG a dirt-simple ``glue'' format
around PNG or a complex multimedia format capable of integrating animations,
audio and even video. By mid-1998, MNG had settled down to something in
between;
while it has fairly extensive animation and image-manipulation capabilities,
there is no serious expectation that it will ever integrate audio or video.
(Those are best handled by MPEG, particularly MPEG-4.)
The MNG specification was promoted to ``1.0 status'' on 11 January 2001, in
accordance with an official vote of the MNG developers, and the final, edited
version was released on 31 January 2001.
MNG includes a number of interesting features:
* object or sprite-based approach to animation, with commands to move, copy
and paste images (rather than replicate them as in GIF)
* nested loops for complex animations
* way better compression than GIF animations
* support for difference (or ``delta'') images for still better compression
* integration of both PNG and JPEG-based (``JNG'') images
* support for transparent JPEG images
* low-complexity and very low-complexity subsets for simpler implementation
Of course, MNG also shares a number of PNG's best features:
* unambiguous pronunciation (gotta love it)
* multiple CRCs so that file integrity can be checked without viewing
* ultra-clever magic signature that can detect the most common types of
file
corruption
* non-patented (you betcha!) compression, either completely lossless (PNG)
or lossy (JPEG)
* full alpha support (multi-level transparency) for all image objects
* gamma and color correction for cross-platform consistency
* ability to store copyright and other textual info, either compressed or
uncompressed
* full Year 2000 (Y2K) support (good for at least 63 millenia! dang!)
MNG has a separate mailing list for discussions about the specification,
programming, and so forth:
* send subscribe mng-list in the body of a message to
majordomo()ccrc.wustl.edu to subscribe
MNG does not share PNG's MIME type:
* unregistered Internet media types: video/x-mng and image/x-jng
_________________________________________________________
added clib2 version and adjusted the directory tree to respect the SDK standard
| |