Due the interest in uploading files in FITS format, I propose to add support for it. This is a pretty popular format in astronomy, and it contains a lot of metadata.
The format was created in 1981, and its updates are released by NASA, so there should not be problems with patents and licenses.
ImageMagick (and many other libraries) supports it, so there's no problem with generating previews.
File extension: .fits, .fit and .fts.
MIME types: image/fits and application/fits.
Spec info: https://www.loc.gov/preservation/digital/formats/fdd/fdd000317.shtml and http://www.cv.nrao.edu/fits/
- Real files are usually large enough. For example, I have an example of 380 MB and 182 MPX. On my laptop, the generation of JPEG thumbnails takes about 6 seconds.
- A single image can contain multiple frames. Therefore, it is desirable to make either paging output support (like PDF) or frame-by-frame animation (like GIF).