In tese docs I am often referring to the "efficient" processing of acm images. This is
necessary becasue of the nature of the data: lots of images on a very slow computer.
What I mean by "efficiency" has to do with speed of action and clarity of process. How
quickly can we perform a task, and is the process procedually clear? Here are some
things to consider.
- We first need a way to make a list of the images in a PAS directory (this is currently
solved with the pas_imlistgen. Each time that
routine is run we get a complete list (list.IMAGES) of all PAS fits images in the directory
that is specified by the (BaseDir,Date) files.
- The acm_table_markII code takes the list.IMAGES
file and surveys header information in each image to compile a table file. This code is optimized
to work on lists of images. It uses only header information, and has some specialized routines
to derive info specific to acm image (e.g. is an image type bias?, open?, etc...). Following
a run of acm_table_markII we always have a table file (ACMDAT) that summarizes the complete
contents of the PAS image subdirectory.
- Each acm_table_markII run works on only the most recently
added images. By leaving the list.IMAGES file from a previous run in place, the core will
establish a working list for only the new images in the directory. This is important for running on mcs DURING a
night of observing. We want to process only new images and them add their information to the
current ACMDAT table.
- We'll often want to take an image list (whether a full list.IMAGES, or a list of new images)
and process the contents. The reseults may be processed images that we place in a local
depository named "./local_red/". In fact, there will be an additional subdirectory that
conveys what kine of operation was performed. For example acm images with header repair
and ficed biass pattern (FBP) correction might be placed into ".local_red/FIXUP".
- We'll likely want the ability to have the ACMDAT table have access to the processed
versions of images. In other words, when I use point_selector)
to view an image, I usually want to be viewing the most "processed" version of the image. Maybe
I want a quick way to revert back to the original images or some earlier processing step.
Hence, we need a tool that can read a list of images, and prepare a revised set of
corresponding image paths that can be used with the ACMDAT table.