toasty tile-study

The tile-study command takes a single large study image and breaks it into a high-resolution layer of tiles.

Usage

toasty tile-study
   [standard image-loading options]
   [--placeholder-thumbnail]
   [--outdir DIR]
   [--name NAME]
   [--avm]
   [--avm-from PATH]
   [--fits-wcs PATH]
   IMAGE-PATH

See the Standard image-loading options section for documentation on those options.

The IMAGE-PATH argument gives the filename of the input image. For this usage, the input image is typically a very large astrophotography or data image that needs to be tiled to be displayed usefully in AAS WorldWide Telescope.

The --outdir DIR option specifies where the output data should be written. If unspecified, the data root will be the current directory.

The --name NAME option specifies the descriptive name for the imagery to be embedded inside the output WTML file. It defaults to “Toasty”.

If the --placeholder-thumbnail argument is given, an all-black placeholder thumbnail will be created. Otherwise, the thumbnail will be created by downsampling the input image. This operation can actually be the most memory-intensive part of the process, and can yield poor results with mostly-empty images. You can avoid this by using this argument and then invoking toasty make-thumbnail with a better-suited input image.

If the --avm argument is given, Toasty will attempt to load world-coordinate information from AVM (Astronomy Visualization Metadata) tags in the input image’s metadata. This isn’t checked automatically because this functionality requires the pyavm package to be installed on your system.

The --avm-from PATH argument is like --avm, but loads the AVM information from a different image file. This can be useful if you have multiple files with different versions of the same image, and the one that you want to tile has broken or missing AVM. It is up to you to ensure that information contained in the AVM file corresponds to the main input image.

If the --fits-wcs argument is given, Toasty will attempt to load world-coordinate information from the headers of the named FITS file. It is up to you to ensure that information contained in that file corresponds to the main input image. This argument can be useful with the output from Astrometry.Net, which generates WCS FITS files for the images it solves.

Notes

For correct results the source image must be in a tangential (gnomonic) projection on the sky. For images that are small in an angular sense, you might be able to get away with fudging the projection type.

If the input image does not contain any useful astrometric information, the emited index_rel.wtml file will contain generic information that makes the image 1° wide and places it at RA = Dec = 0.

See Also