SkyView uses the ImageJ software library to generate all of the quicklook (JPEG, GIF, TIFF, PNG, …) images it uses. ImageJ is a very powerful public domain package for analyzing and manipulating images. A full implementation of ImageJ is included in the SkyView jar. The last time we updated this was a several years ago when we went to ImageJ version 138k. ImageJ is now at Version 149b, and we thought it was time to catch up.
If you use the SkyView jar directly, you can run ImageJ to analyze SkyView images by just adding the ImageJ setting, e.g.,
java -jar skyview.jar position=3c273 survey=dss imagej
This will start an ImageJ session with your SkyView images loaded in. There are a lot of new capabilities in ImageJ including some for combining images to produce animations that we may use in SkyView or other tools.
The change shouldn’t affect users — unless you’re already using ImageJ as described above. Then you’ll get the benefit of several years of enhancements and upgrades to ImageJ.
Note that the version of ImageJ used in SkyView is very slightly changed from the standard distribution. The most significant change is we enhanced the text plotting capabilities to allow for text at arbitrary angles. We use that for our coordinate and contour gridding.