WMZ to AVIF Converter

WMZ is a compressed variant of the Windows Metafile (WMF) format, introduced by Microsoft with Office 2000 in 1999. A WMZ file is simply a WMF file compressed using the gzip algorithm (RFC 1952), reducing the file size for more efficient storage and embedding within Office documents, web pages, and other containers. The underlying WMF format stores vector graphics as a sequence of GDI (Graphics Device Interface) function calls — commands that draw lines, curves, polygons, text, and bitmaps — recorded in a device-independent format that can be replayed at any resolution. WMZ preserves this vector nature: when decompressed, the file produces a standard WMF that renders through the Windows GDI subsystem using the same drawing primitives as on-screen display, ensuring visual fidelity across different output devices and resolutions. WMZ files are commonly found embedded in Microsoft Office documents (Word, Excel, PowerPoint), HTML email messages generated by Outlook, and web content produced by Office's Save as Web Page feature. The format is also used for clip art and template graphics distributed with Office installations. One advantage is space efficiency: gzip compression typically reduces WMF file sizes by 60-80%, meaningful when many small graphics are embedded in a single document or web page. The format's deep integration with the Microsoft Office ecosystem is another practical strength — WMZ graphics render natively in all Office applications without additional software, and can be extracted, decompressed, and converted using tools like LibreOffice, ImageMagick, Inkscape, and standard gzip utilities.