This is a translator for PDF files based on the MuPDF library.
By installing this translator, any application that's using Haiku's data translation system to load images, will be able to open a PDF as an image.
With ShowImage, for example, you can even browse through multi-page PDFs with its 'Next/Previous page' menu items. WonderBrush, on the other hand, will only load the very first page.
The DataTranslations preferences provide settings for DPI and antialiasing.