wwt-aligner go

This command runs one alignment, from start to finish.

Synopsis🔗

A typical invocation is:

wwt-aligner go
    -o {OUTPUT-PATH}
    {RGB-PATH}
    {FITS-PATH} [FITS-PATHS ...]

This command analyzes one or more FITS files (FITS-PATH...) to produce Astrometry.Net “indices” giving the locations of stars on the sky, then finds star-like sources in the input RGB image (RGB-PATH) and solves for their alignment relative to the FITS files. A new output image (OUTPUT-PATH) is created that augments the input image with AVM coordinate metadata.

For the time being, the output image must be in PNG or JPEG format because we are currently unable to export AVM data to other formats. If the input image is not in one of these formats, it will be converted.

Detailed Usage🔗

wwt-aligner go
    -o|--output {OUTPUT-PATH}
    [-t|--tile TILE-PATH]
    [-W|--workdir WORK-PATH]
    [--anet-bin-prefix PREFIX]
    {RGB-PATH}
    {FITS-PATH} [FITS-PATHS ...]

If the -t TILE-PATH option is provided, the output image will be “tiled” into the AAS WorldWide Telescope format with the output files placed into the new directory identified by the TILE-PATH argument. This directory will include the tiled image data (a set of small PNG files) and an index_rel.wtml WTML file containing the astrometric metadata. If you use this option, you can then check your alignment in WWT by using the wwt-aligner preview command:

$ wwt-aligner go -o aligned.jpg -t tiled input.tif reference.fits
$ wwt-aligner preview tiled/index_rel.wtml

The -W WORK-DIR option causes the tool to save its working files in the specified directory, as opposed to using a temporary directory. This can be useful for low-level debugging of the alignment process.

The --anet-bin-prefix option can be ignored in almost all use cases. If you are testing the agent outside of the Docker container, you can use it to tell the agent where to find the Astrometry.Net programs.

The generic command-line arguments are also supported.

Remarks🔗

FITS inputs🔗

The aligner will make its best efforts to extract useful image data out of each input FITS file that is passed to it. If it is unable to find such image data, it will simply ignore that input FITS file. Please file a bug if you have an example FITS file that the aligner is unable to properly process.

See Also🔗

• wwt-aligner preview