[M4IF Technotes] X3D/XMT compatibility

[Sebastian Voigt]

Hello
I try the same. Take the nodes under the <scene> element in X3D and append them to an children-node of an groupe-node in an XMT-A-Document. X3D allows more then one top-level-node as childs of the scene-element, XMT-A allows only one. ROUTEs must be after the top-level-node as childs of scene-element. PROTODeclares are first childs of scene-element.
My XMTs have the following structure (starting at scene-element):
<scene>-
              |
              | ---<ProtoDeclare> {0..n}
              |
              | ---i.e. <OrderedGroup>-
                                                 |
                                                 | --- [your x3d nodes]
              |
              | --- <ROUTE> {0..n}
The header of the XMT-A includes the IOD. If you like build self-contained MP4-Files, you must append to the Body-node an ObjectDescriptorUpdate-Node for referenced mediafiles, i.e. for image textures and replace the url-strings of such references with the OD_ID.
Best regards
Sebastian
----- Original Message ----- 
  From: tm991058 
  To: technotes   lists.m4if.org 
  Sent: Wednesday, March 19, 2024 7:36 PM
  Subject: [M4IF Technotes] X3D/XMT compatibility
  hello all,
  I'm an austrian student from the college for telecommunication and media. At present I'm working at my diploma project, which is about authoring MPEG4-scenes.
  I have already made a test-3d scene and exported it to vrml...than I converted it to x3d..
  The next steps would be to make a xmt file out of the x3d file, than to get bif out of this and than finaly get a mp4 scene...
  My present problem is: How can I get from x3d to xmt??
  I haven't found any converters and I haven't found any rules how to change the x3d code by hand (in a text editor) to get to xmt...
  I've heard a lot about the interoperability and compatibility between xmt and x3d... I've read a lot about the compromise and the compact form of x3d..  someone claimed that it is easy to get from x3d to xmt because of the compromise form... i've found many statements that there is a high compatibility between xmt-a and x3d... but nobody is writing about a practical method to get from x3d to xmt...
  Maybe I wrap something...
  I would be really glad to hear from someone of you!
  Thanks very much in advance!
  karin
-------------- next part --------------
An HTML attachment was scrubbed...
URL: /pipermail/mp4-tech/attachments/20030320/dc68bfaf/attachment.html