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MPEG-4 is an ISO/IEC standard developed by MPEG (Moving Picture Experts = Group), the committee that also developed the Emmy Award winning = standards known as MPEG-1 and MPEG-2. These standards made interactive = video on CD-ROM and Digital Television possible. MPEG-4 is the result of = another international effort involving hundreds of researchers and = engineers from all over the world. MPEG-4, whose formal ISO/IEC = designation is ISO/IEC 14496, was finalized in October 1998 and became = an International Standard in the first months of 1999. The fully = backward compatible extensions under the title of MPEG-4 Version 2 were = frozen at the end of 1999, to acquire the formal International Standard = Status early in 2000. Some work, on extensions in specific domains, is = still in progress.=20 MPEG-4 builds on the proven success of three fields:=20 a.. Digital television;=20 b.. Interactive graphics applications (synthetic content);=20 c.. Interactive multimedia (World Wide Web, distribution of and access = to content)=20 MPEG-4 provides the standardized technological elements enabling the = integration of the production, distribution and content access paradigms = of the three fields.=20 More information about MPEG-4 can be found at MPEG's home page (case = sensitive): http://mpeg.telecomitalialab.com . This web page contains = links to a wealth of information about MPEG, including much about = MPEG-4, many publicly available documents, several lists of "Frequently = Asked Questions" and links to other MPEG-4 web pages. The standard can = be bought from ISO, send mail to sales@iso.ch. Notably, the complete = software for MPEG-4 version 1 can be bought on a CD ROM, for 56 Swiss = Francs. It can also be downloaded for free from ISO's website: = www.iso.ch/ittf - look under publicly available standards and then for = "14496-5". This software is free of copyright restrictions when used for = implementing MPEG-4 compliant technology. (This does not mean that the = software is free of patents.=20 ------=_NextPart_000_009C_01C4101B.6A5A9820 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=3DContent-Type content=3D"text/html; = charset=3Diso-8859-1"> <META content=3D"MSHTML 6.00.2800.1264" name=3DGENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=3D#ffffff> <DIV>Dear EM TC Member -</DIV> <DIV> </DIV> <DIV>Discussion Item 1:</DIV> <DIV> </DIV> <DIV>At the last GIS SC meeting we discussed the issue of whether WGS 84 = -=20 Lat/Long is adequate for this go around of the CAP specification. = The issue=20 was raised with regard to using USNG-NAD83. The unanimous consensus of = the group=20 was that <SPAN class=3D219093817-16032004>USNG is for use at the user = interface=20 level. Therefore, for a message protocol, such as CAP WGS = 84 -=20 Lat/Long is adequate and CAP spec should remain the way = it is.=20 Further, by leaving CAP with WGS 84 - Lat/Long, the CAP spec remains = more=20 international in nature and not restricted to the US market = space.</SPAN></DIV> <DIV><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV><SPAN class=3D219093817-16032004>Also, by way of = clarification, Dave=20 Danko (ESRI) added: </DIV> <BLOCKQUOTE dir=3Dltr style=3D"MARGIN-RIGHT: 0px"> <DIV><SPAN class=3D219093817-16032004><FONT face=3DArial = color=3D#0000ff size=3D2>NAD=20 83 vs WGS 84: Technically these are the same for mapping, charting, = and=20 navigation purposes. Geodetically, of course they are different but I = think=20 they are the same for our purposes. To keep this standard = international we=20 should use WGS 84. Perhaps in a users guide for the US it could be = mentioned=20 that NAD 83 coordinates work fine here and that NAD 83 coordinates = could be=20 used. However (Carl's note), this would mean that we would need some = code to=20 allow the receiving application to know that the coordinates are NAD = 83 and=20 not WGS Lat/Long.</FONT></SPAN></DIV></BLOCKQUOTE> <DIV dir=3Dltr><SPAN class=3D219093817-16032004>As we are working at an = accuracy=20 level of many feet/meters, the geodetic differences are not=20 important.</SPAN></DIV> <DIV dir=3Dltr><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV dir=3Dltr><SPAN class=3D219093817-16032004>We then went on to = discuss the issue=20 of "altitude" and "ceiling" notes section. We<SPAN=20 class=3D219093817-16032004> think the words "per the WGS 84 datum" = should be=20 removed. We think that this phrase will add communication = confusion,=20 especially for the geographically literate.</SPAN> <DIV><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV><SPAN class=3D219093817-16032004>The WGS ellipsoid is a best fit = around the=20 world and differs from MSL by varied amounts around the world. So does = one=20 put a value here, including/excluding the delta from the = WGS-84=20 ellipsoid, a height referenced to the ellipsoid? What is = the=20 meaning of the value here? I think we should just have it from (local) = MSL for=20 the area of interest. (With ellipsoid heights there is a danger of = having to=20 provide negative values for areas above sea level). </SPAN><SPAN=20 class=3D219093817-16032004>This would be plenty specific for the = purposes intended=20 for this standard. </SPAN><SPAN class=3D219093817-16032004>Perhaps this = should be=20 corrected in a future version of the standard.</SPAN></DIV> <DIV><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV><SPAN class=3D219093817-16032004>Discussion Item 2: </SPAN></DIV> <DIV><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV><SPAN class=3D219093817-16032004>Rex brought up a discussion on the = fact that=20 the Web3D consortium (geoVRML) is looking at doing more with spatial = within the=20 portrayal domain. This can be seen on their web page. Rex said he would = try to=20 find out more information as to what they are actually trying to=20 do.</SPAN></DIV> <DIV><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV><SPAN class=3D219093817-16032004>Discussion item 3:</SPAN></DIV> <DIV><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV><SPAN class=3D219093817-16032004>ISO MPEG4 - Looking at streaming = of=20 geo-visualization in the mobile world. There may be IP and royalty = issues=20 here.</SPAN></DIV> <DIV><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV><SPAN class=3D219093817-16032004>From the MPEG Standards Org=20 site:</SPAN></DIV> <DIV><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV><SPAN class=3D219093817-16032004> <P class=3Dbody align=3Djustify>MPEG-4 is an ISO/IEC standard developed = by MPEG=20 (Moving Picture Experts Group), the committee that also developed the = Emmy Award=20 winning standards known as MPEG-1 and MPEG-2. These standards made = interactive=20 video on CD-ROM and Digital Television possible. MPEG-4 is the result of = another=20 international effort involving hundreds of researchers and engineers = from all=20 over the world. MPEG-4, whose formal ISO/IEC designation is ISO/IEC = 14496, was=20 finalized in October 1998 and became an International Standard in the = first=20 months of 1999. The fully backward compatible extensions under the title = of=20 MPEG-4 Version 2 were frozen at the end of 1999, to acquire the formal=20 International Standard Status early in 2000. Some work, on extensions in = specific domains, is still in progress. </P> <P class=3Dbody align=3Djustify>MPEG-4 builds on the proven success of = three fields:=20 <UL class=3Dbody> <LI>Digital television;=20 <LI>Interactive graphics applications (synthetic content);=20 <LI>Interactive multimedia (World Wide Web, distribution of and access = to=20 content) </LI></UL> <P class=3Dbody>MPEG-4 provides the standardized technological elements = enabling=20 the integration of the production, distribution and content access = paradigms of=20 the three fields. </P> <P class=3Dbody align=3Djustify>More information about MPEG-4 can be = found at MPEG's=20 home page (case sensitive): <A class=3Dl2=20 href=3D"http://www.m4if.org/mpeg4/www.chiariglione.org/mpeg/">http://mpeg= .telecomitalialab.com</A>=20 . This web page contains links to a wealth of information about MPEG, = including=20 much about MPEG-4, many publicly available documents, several lists of=20 "Frequently Asked Questions" and links to other MPEG-4 web pages. The = standard=20 can be bought from ISO, send mail to <A class=3Dl2=20 href=3D"mailto:sales@iso.ch">sales@iso.ch</A>. Notably, the complete = software for=20 MPEG-4 version 1 can be bought on a CD ROM, for 56 Swiss Francs. It can = also be=20 downloaded for free from ISO=92s website: <A class=3Dl2=20 href=3D"http://www.iso.ch/ittf">www.iso.ch/ittf</A> - look under = publicly=20 available standards and then for "14496-5". This software is free of = copyright=20 restrictions when used for implementing MPEG-4 compliant technology. = (This does=20 not mean that the software is free of patents. </P></SPAN></DIV> <DIV><SPAN class=3D219093817-16032004></SPAN> </DIV> <DIV><SPAN=20 class=3D219093817-16032004></SPAN> </DIV></SPAN></DIV></SPAN></BODY>= </HTML> ------=_NextPart_000_009C_01C4101B.6A5A9820--
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