Full Name	WMF (Windows Metafile Format)
Format ID	IG_FORMAT_WMF = 44
File Extension(s)	*.wmf,
Data Type	Metafile Image
Data Encoding	Binary
ImageGear Multipage Support	No
ImageGear Alpha Channel Support	No
ImageGear Platforms Support	WIN32, WIN64, Unix (read raster portion only). MAC (read raster portion only)

ImageGear Supported Versions:

• Version 1 Metafiles prior to Windows 3.0
• Version 2 Metafiles for Windows 3.0 and later

ImageGear Supported Features:

• IG_FLTR_DETECTSUPPORT - autodetection
• IG_FLTR_PAGEREADSUPPORT - single page file reading
• IG_FLTR_PAGEINSERTSUPPORT - single-page file writing

ImageGear Read Support:

• IG_COMPRESSION_NONE:
  • Indexed RGB: 1, 4, 8 bpp;
  • RGB: 24 bpp
• IG_COMPRESSION_RLE:
  • Indexed RGB: 4, 8 bpp

ImageGear Write Support:

• IG_COMPRESSION_NONE:
  • Indexed RGB: 1, 4, 8 bpp;
  • RGB: 24 bpp
• IG_COMPRESSION_RLE:
  • Indexed RGB: 4, 8 bpp

ImageGear Filter Control Parameters:

Filter Control Parameter	Type	Default Value	Available Values	Description
UPSIDE_DOWN	BOOL		TRUE, FALSE	If TRUE then images will be saved upside-down.
TYPE	UINT		BMP_TYPE_BMC, BMP_TYPE_BMI, BMP_TYPE_BMI2	Type of the BMP file to be saved as part of WMF.
COMPRESSION	DWORD		BMP_COMP_RLE4, BMP_COMP_RLE8, BMP_COMP_RGB	Type of compression of BMP file.
TRUE_METAFILE	BOOL	TRUE (for Windows); FALSE (otherwise)	TRUE, FALSE	TRUE means executing of metafile commands (playing of metafile). Can be TRUE only for Windows. If the TRUE_METAFILE parameter is set to TRUE, the image will be opened as an RGB DIB for use with the GDI functions, which produce the image output. This causes the image to look like it is 24-bit per pixel, and 1024x1024 in dimensions. If the TRUE_METAFILE parameter is set to FALSE, then ImageGear will open the image according to its correct bit depth and dimensions.
RESOLUTION_X	DWORD	NULL		X resolution. 0 for actual resolution.
RESOLUTION_Y	DWORD	NULL		Y resolution. 0 for actual resolution.
DEPTH	DWORD	NULL		Bit Depth. 0 for actual depth.

Comments:

A Microsoft Windows Metafile holds vector and bitmap graphics data in memory or on disk. Although it was developed for use with Windows applications, it is now used by many non-Windows-based applications, allowing data to be transferred to and from Windows applications. Due to the great success of the Microsoft Windows interface, the Windows Metafile format is found in nearly all graphical applications. Metafiles use much less space and are more device-independent than bitmaps.

See also the section Support for Metafile Formats.

The Windows metafile begins with a short header and is followed by one or more records of data. The header describes the record data. A "placement" header can also be added before the file header; it contains information needed to move the metafile between applications. Each record corresponds to a binary-encoded Windows graphics device interface (GDI) call, and contains the size of the record, the unique function number for the GDI and an array of parameters. The GDI is used by Windows to perform all image output. When the metafile is "played", (this Microsoft term is a companion term to the Windows function named "PlayMetaFile"), each record makes a call to the appropriate function call for displaying each object in the image. The last record in the file contains a function number of zero to indicate that the end of the record data has been reached.

References Used:

Brown, C. Wayne, and Barry J. Shepherd. Graphics File Formats: Reference and Guide. Greenwich, CT.: Manning Publications, 1992.

Kay, David C. and John R. Levine. Graphics File Formats. Windcrest Books, 1992.

Murray, James D. and William vanRyper. Encyclopedia of Graphics File Formats. Sebastopol, CA: O'Reilly & Associates, Inc., 1994.

Petzold, Charles. Programming Windows: The Microsoft Guide to writing applications for Windows 3. Redmond, WA: Microsoft Press, 1990.