Content Pipeline Guide > Customizing Publishing > Controlling Graphics Conversion for HTML-Based Publishing
  
Controlling Graphics Conversion for HTML-Based Publishing
When publishing documents to HTML (Publish > For Web and Publish > For HTML File), Arbortext Editor and Arbortext Publishing Engine copy graphics with GIF, JPEG, and PNG file formats. Other graphic file formats are converted to GIF during the publishing process.
If you do not want Arbortext Editor and Arbortext Publishing Engine to convert your graphics, you can use the APTCOPYGRAPHICEXTS environment variable to override the list of graphic file formats that Arbortext Editor and Arbortext Publishing Engine automatically convert.
The format for this is a comma-delimited list of extensions (case-insensitive) that Arbortext Editor or the Arbortext Publishing Engine will copy instead of converting. In the following DOS example,
set APTCOPYGRAPHICEXTS=gif,jpg,jpeg,png,tif
the GIF, JPG, PNG, and TIF file formats will be copied instead of converted.