There are two ways to generate "thumbnail" images. One is to build a full-resolution mosaic and shrink it down using mShrink to the scale desired. This process can be costly if the full resolution image is not desired (or not desired yet). It is much faster to mosaic at the scale of the thumbnail itself. One reason for doing this could be to evaluate whether th full-resolution mosaic is worth building at all.

mShrinkHdr is a simple utility that takes a FITS header template (such as might come out of mMakeHdr or mHdr) and make a new one at a differenc pixel scale. The default scale for this new header is 200 pixels, though the user can override this with any value.

mShrinkHdr [-d][-s scale] template.hdr shrunken.hdr


Turn on debugging.
-s scale
Set the size in pixels of the larger axis.


Original FITS header template.
"Thumbnail" FITS header template.
If successful, the result is a new FITS header template with a size and pixel scale appropriate to making a thumbnail mosaic.


$ mShrinkHdr region.hdr thumbnail.hdr
[struct stat="OK"]

Return Codes:

  • [struct stat="ERROR", msg="Usage: mShrinkHdr [-d][-s scale] template.hdr shrunken.hdr"]
  • [struct stat="ERROR", msg="Cannot open output template file"]
  • [struct stat="ERROR", msg="Bad template: filename"]
  • [struct stat="ERROR", msg="Output wcsinit() failed."]