MIME (Multipurpose Internet Mail Extensions) is a specification for formatting non-ASCII messages so they can be sent over the Internet. ProjectWise uses file MIME types for various purposes, including integration with MicroStation and AutoCAD, for attribute exchange, and for the new photo preview feature in ProjectWise V8i. Some well-known file types may not get a MIME type assigned in ProjectWise, due to the fact that ProjectWise currently does not need a MIME type value in order to correctly process those file types. This is the intended behavior.
Since setting the document MIME type during a database conversion is an optional task, it is important to understand when and why the MIME type conversion should be performed when upgrading ProjectWise datasources from pre-V8 XM Edition versions to V8 XM Edition or V8i.
The purpose of this document is to explain:
MIME type management was introduced in ProjectWise V8 XM Edition (22.214.171.124) to support the distributed DGN functionality. Because only V8 DGN files can be made shareable, ProjectWise uses the MIME type of each DGN file to determine whether it is a V8 DGN or a V7 DGN. For this reason, V7 DGN files and V8 DGN files have been assigned different MIME types:
When files are imported into ProjectWise, ProjectWise stores the MIME type of each file in the database, and use that database value to determine whether the DGN file can be made shareable or not.
ProjectWise also uses the file MIME type for AutoCAD reference file management. When you check in or update the server copy of a master DWG file, any changes to the master file that affect its reference set information are then updated in the database. In order for this database update to occur, the MIME type of your DWG files must be set to image/vnd.dwg
Starting with the 8.9.4 version of ProjectWise V8 XM Edition, all types of attribute exchange require the proper MIME type to be set for the document. This includes:
For ProjectWise V8i, the attribute exchange configuration information is stored in the computer registry in the following location:
For ProjectWise V8 XM Edition, the attribute exchange configuration information is stored in the computer registry in the following location:
Under each version's keys there are sub-keys for each application:
Under each of these sub-keys there will be following registry values:
This value is a list of all MIME types that are supported by a given updating system. Therefore, a document must have one of these MIME types set to have any attributes updated. Otherwise, no attribute update will occur for that specific document.
Dynamically downloading, or streaming, raster data with integrated MicroStation was introduced in the 126.96.36.199 version of ProjectWise V8 XM Edition. This technology depends on the raster file that is being streamed having a ProjectWise MIME type set to "raster".
ProjectWise V8i introduces the Photo Preview tab to the Preview pane in ProjectWise Explorer, which out of the box displays digital images and Microsoft Office documents. Additionally, the Photo Preview tab can be extended to display additional file types, such as Adobe PDFs, HTML and text files. When you select a document in the document list and then select the Photo Preview tab, a copy of the document is downloaded to your local working directory, and then displayed in the Photo Preview tab. To determine whether a document should be copied to the local working directory and displayed, ProjectWise checks the MIME type of the file. If the MIME type is not set, or not set to the correct value for the application, the document will not be copied out and displayed. The DMSCONV tool will set these MIME types correctly.
The table below shows the correct MIME type settings for files to display correctly in the Photo Preview tab.
ProjectWise Mime Type
png, tif, jpg, bmp, gif
When you create a document in ProjectWise, whether by using a document creation wizard, no wizard, or by dragging files from the file system, ProjectWise sets the MIME type, if known, for each file. MIME types are stored in the DMS_DOC table, in the O_MIMETYPE field. However, pre-V8 XM Edition datasources have no concept of MIME types. When pre-V8 XM Edition datasources are upgraded to V8 XM Edition or V8i, the MIME types will still not be determined. To set MIME types for these files, a MIME type bulk update must be performed. This can be accomplished using the DMSCONV tool. The DMSCONV tool will prompt the user to update the MIME types of these files as part of the database upgrade to a V8 XM Edition or V8i platform. This does not have to be done as part of the conversion; it can be run after a datasource is converted. The DMSCONV tool will issue a MIME query command to the storage area for each file to determine the MIME type; note that this is a read-only operation, and the file is NOT transferred or modified during this process.Also, the MIME type conversion process can also be stopped before completion, and when run at a later time, the process will start up where it left off and not reprocess files it has already processed. Because not all file types need to have a MIME type assigned, the MIME type determination process can be accelerated by defining an exclusion list on the DMSCONV command line. Files with matching extensions will be ignored for MIME type determination purposes. See the DMSCONV command-line help for examples.While it is always recommend having your database completely up-to-date, including MIME types, you can assess how time-critical it is to have all MIME types converted. Upgrading the MIME types from a pre-V8 XM datasource is most important for reference file handling in AutoCAD, and for attribute exchanges\title block updates.
Initial Release Version
MicroStation Distributed DGNs
AutoCAD Reference File Management
MicroStation and AutoCAD Titleblocks
Microsoft Office Attribute Exchange
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