Also Known As: MET
| Type | Metafile |
| Colors | Unlimited |
| Compression | RLE |
| Maximum Image Size | NA |
| Multiple Images Per File | Yes |
| Numerical Format | Little-endian |
| Originator | Microsoft Corp., IBM |
| Platform | OS/2 |
| Supporting Applications | Various under OS/2 Presentation Manager |
| See Also | Microsoft Windows Metafile, OS/2 Bitmap |
Usage
Storage and transport of graphics information associated with the OS/2 Presentation Manager GUI. Seldom found ouside the OS/2 environment.
Comments
A complex format mainly consisting of aliased calls to Presentation Manager supporting libraries. Difficult to support outside of that environment.
Vendor specifications are available for this format.
Presentation Manager Metafile (MET) files are used to store vector- and bitmap-format image data in memory or in disk files, for later playback to an output device. Although the Presentation Manager Metafile format is specific to IBM's Presentation Manager for OS/2, many third-party applications support this format as a method for interchanging data between applications under OS/2. Because of the confusion in the market engendered by the IBM-Microsoft split, and the subsequent increase in the installed base of Microsoft Windows, Presentation Manager Metafile has found little support in the larger market, even though the OS/2 installed base is substantial.
Contents:
File Organization
File Details
For Further Information
Presentation Manager Metafiles consist of a sequence of what IBM calls structured fields, which are followed by the actual data. Structured fields and the associated data are organized into one or more functional components, which are large blocks of data--documents, for instance, or complex graphics objects. These functional components are delimited by "begin-component" and "end-component" structured fields.
Structured fields start with the following header:
typedef struct _MetHeader
{
CHAR Length[2];
CHAR ID[3];
BYTE Flags;
CHAR SegSeqNum[3];
} MetHeader;
Length is the length of the field, in bytes.
ID is a field identifier.
Flags contains Boolean information related to the disposition of the field by the rendering application. Currently this is always 0.
SegSeqNum contains what IBM calls a segment sequence number. Again, this is currently always 0.
Following the header structure, which is common to all structured fields, is information that IBM calls positional information. This information extends the header; its exact nature depends on the actual structured field. Following these positional fields are what IBM calls triplets, which consist of a short header of the following form:
typedef struct _Triplet
{
BYTE Length;
BYTE ID;
} Triplet;
Length is the length in bytes of the triplet header and the following data.
ID contains a value identifying the triplet.
Following this header is the actual data associated with the triplet. The bulk of the data found in the metafile is located here.
Structured fields defined in the documentation are listed below.
Field Name | Field ID | Parameters | Triplets |
|---|---|---|---|
Begin Document |
D3A8A8 |
10 bytes |
3 |
Begin Resource Group |
D3A8C6 |
08 bytes |
0 |
Begin Color Attribute |
D3A877 |
08 bytes |
0 |
Color Attribute Table |
D3B077 |
03 bytes |
(varies) |
End Color Attribute Table |
D3A977 |
08 bytes |
0 |
Begin Image Object |
D3A8FB |
08 bytes |
0 |
Begin Resource Group |
D3A8C6 |
08 bytes |
0 |
End Resource Group |
D3A9C6 |
08 bytes |
0 |
Begin Object Environment Group |
D3A8C7 |
08 bytes |
0 |
Map Color Attribute Table |
D3AB77 |
02 bytes |
2 |
Image Data Descriptor |
D3A6FB |
09 bytes |
0 |
Image Picture Data |
D3EEFB |
(varies) |
(varies) |
End Image Object |
D3A9FB |
08 bytes |
0 |
Begin Graphics Object |
D3A8BB |
08 bytes |
0 |
Map Coded Font |
D3AB8A |
02 bytes |
3 |
Map Data Resource |
D3ABC3 |
02 bytes |
2 |
End Object Environment Group |
D3A9C7 |
08 bytes |
0 |
End Graphics Object |
D3A9BB |
08 bytes |
0 |
End Resource Group |
D3A9C6 |
08 bytes |
0 |
End Document |
D3A9A8 |
08 bytes |
0 |
Perhaps the most common structured field is the Graphics Data Descriptor, which contains the actual graphics data: |
|||
Graphics Data Descriptor |
D3A6BB |
|
|
Parameter information associated with the Graphics Data Descriptor provides an elaborate description of the following data, which takes the place of what might be encoded in another format as a long, complex header. Its length varies, but it may be several hundred bytes long. Please see the specification included on the CD-ROM for details and further information. (Note that the document appears to contain an incomplete list of the structured fields likely to be found in a Presentation Manager Metafile.)
For further information about the Presentation Manager Metafile format, see the specification included on the CD-ROM.
Presentation Manager Metafile is also documented in the following IBM publication:
IBM Corporation, OS/2 2.0 Technical Library Presentation Manager Programming Reference Volume III, Part Number 10G627.
Relevant information is contained in Appendixes D, G, and F of the IBM publication. This document is available for purchase through your local IBM dealer or salesperson.
Support responsibility for OS/2 is now solely in the hands of IBM. For information, contact:
IBM Corporation
Attn: Independent Vendor League
150 Kettletown Road
Southbury, CT 06488
Voice: 203-266-2000
WWW: http://www.ibm.com/
OS/2 and the Presentation Manager Metafile format originated at Microsoft, and some documentation is still available there. You may be able to get some information by contacting:
Microsoft Corporation
One Microsoft Way
Redmond, WA 98052-6399
Voice: 206-882-8080
Voice: 800-426-9400
FAX: 206-883-8101
WWW: http://www.microsoft.com/
Also see the following resources:
OS/2 Resource listing
OS/2 Archive at Walnut Creek CD-ROM
You might also be able to find some helpful information at the OS/2 shareware BBS:
Voice: 703-385-0201
BBS: 703-385-4325
WWW: http://www.os2bbs.com/
Telnet: bbs.os2bbs.com
Copyright © 1996, 1994 O'Reilly & Associates, Inc. All Rights Reserved.