4.11.3 Specifying equation output format
For RTF output, the default format for equations is WMF, which is a vector format that generally gives the best rendition. However, if equations do not look right in WMF, try BMP instead. No other choice would give better results. BMP might result in poorer print rendition of equation text, but visual rendition should be nearly as good as WMF:
For HTML output, the default format for equations is JPEG.
See §29.2.5.5 Specifying graphic output format and DPI.
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