WWT Image SetsΒΆ

Images in the AAS WorldWide Telescope can come in a variety of formats:

  • Standard bitmapped images like PNG or JPG files

  • Scientific data in FITS files

  • Large-size images converted into tile pyramids

Such images are described as <ImageSet> XML fragments in several of the WWT file formats. In this package, the corresponding data structure is wwt_data_formats.imageset.ImageSet.

The high-level structure of a standard, minimal WTML file to show a single image is:

<Folder ...>
   <Place ...>
     <ForegroundImageSet ...>
       <ImageSet ...>
         ...
       </ImageSet>
     </ForegroundImageSet>
   </Place>
</Folder>

The corresponding code using wwt_data_formats is:

from wwt_data_formats import folder, place, imageset

f = folder.Folder()
pl = place.Place()
imgset = imageset.ImageSet()

pl.foreground_image_set = imgset
f.children = [pl]

This can then be written to XML with:

from wwt_data_formats import write_xml_doc

with open('myfile.wtml', 'w') as f:
    write_xml_doc(f.to_xml(), dest_stream=f)