Windows Metafile

Revision as of 14:25, 25 July 2016

Windows Metafile (WMF) is a graphics file format used mainly by old Microsoft Windows applications. It stores a list of commands which, when executed, generate an image.

Windows has drivers to support WMF, allowing applications to either write to a WMF file, or draw on the screen, using the same API.

The newer versions of the format are known as Enhanced Metafile (EMF) and Enhanced Metafile Format Plus Extensions (EMF+).

The .wmz extension indicates a ZIP-compressed WMF file. The .emz extension is reportedly used for gzip-compressed EMF files.

Most WMF files begin with a 22-byte "Aldus Placeable Metafile" header, which supplies suggested placement and scaling information. Some (mainly older) WMF files lack this header.

Identification

WMF data (usually?) begins with the byte sequence 01 00 09 00 or 02 00 09 00. This sequence may appear at the beginning of a WMF file, but it is usually at offset 22, and the file begins with the Aldus Placeable Metafile signature of D7 CD C6 9A.

EMF files begin with bytes 01 00 00 00 (representing record type EMR_HEADER), and have ASCII " EMF" (with the leading space) at file offset 40.

Specifications

• Windows Metafile Format Specification
• Windows-Format Metafiles
• Enhanced Metafile Format
• Enhanced Metafile Format Plus Extensions

Metaformat files

• Synalysis grammar file for EMF (for Hexinator / Synalize It!; more details)

Software

• Inkscape
• Konvertor
• libwmf
• XnView

Sample files

• http://cd.textfiles.com/10000gp2/COLORWMF/
• http://cd.textfiles.com/cdreview/cdreview66/MULTIM/MEDI8OR/CLIPART/PICTURES/

See also

• Segmented Hypergraphics

Links

• Wikipedia article
• Microsoft Windows Metafile File Format Summary, from the Encyclopedia of Graphics File Formats.
• Microsoft support: Windows Metafile Functions & Aldus Placeable Metafiles
• MSDN: WmfPlaceableFileHeader structure
• http://wvware.sourceforge.net/caolan/ora-wmf.html