wiki:ImagingTools

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This area is more a grab bag of tools with varying levels of interdependencies.

One thing that many (e.g., Harry Ferguson, [and now Robert too:-)]) have stressed is an equivalent to imexamine. Someone at Subaru (Eric Jenschke) has developed a Python-based visualization tool called ginga. Warren is looking into seeing how easy it would be to add imexamine capaabilties to that tool. [And responding to Ivo's comment, this tool may make sense for source extraction interactions as well.] I'm guessing this will be one primary early effort. But it doesn't hurt to list the other items that need attention. I'm folding into this other image combining algorithms besides drizzle.

Remember, what we develop in Python should not be organized around the IRAF tasks, but rather be a set of tools and capabilities from which we can easily replicate the IRAF task functionality. Some have pointed out that having tasks that go from input file to output file are still very useful, and we should generate similar kinds of tools layered on the basic libraries for convenience in doing very common operations. We may also find that we should write tasks that emulate the IRAF task. Such cases should be judged on an individual basis to see what advantages there are in holding close to the IRAF features.

generic CCD reduction pipelines

immatch/imcoords: basically all the capabilities with in this package (for those that forgot, or never knew in the first place, here are online pages on what these things contain: http://stsdas.stsci.edu/gethelp/pkgindex_images.html ). These basically handle matching items in one image with another, and determining the transforms needed to match the geometrically corrected images. There is heavy overlap with WCS functionality here, and we probably want a very different way of doing these things.

imgeom: applying geometric transforms. Drizzle is one approach. We would support others too. All based on generic WCS tools…

imfit: fitting to features in images

imfilter: filtering tools (with some extra features not present in generic spatial or set filters)

imutil doesn't have a lot that isn't already in numpy or equivalent tools. These may need wrappers to emulate IRAF tasks though.

I think our subsequent work would focus on the WCS related items, but there is a lot of looseness as to what in particular. I think this would help firm up the APIs for our WCS models.

initial iteration

  • implement imexamine-like functionality
    • not necessarily complete in every aspect, but most
  • collect, organize and make consistent existing tools that replace IRAF functionality (e.g., imstat, blkavg)
    • base as much on astropy libraries and conventions
  • start developing an equivalent to ccdproc, in conjunction with astropy efforts.
  • start on tools focused on image registration and coordinate transformations (WCS related issues).
    • geomap, gregister, skymap, xyxymatch, etc

Level 5 Proposed Requirements

imexamine-like tool

  • the imexamine-like tool shall work with ds9
  • the imexamine-like tool shall implement a feature to plot the intensity of a selected row or average of rows (number of rows specified by a parameter)
  • the imexamine-like tool shall implement a feature to plot the intensity of a selected column or average of column (number of rows specified by a parameter)
  • the imexamine-like tool shall implement a feature to plot the intensity of a line through the image at an orientation determined by selecting two locations on the image with the cursor.
  • the imexamine-like tool shall implement a feature to generate a contour plot of the image
  • the imexamine-like tool shall implement a feature to generate a surface plot of the image
  • the imexamine-like tool shall implement a feature to generate a histogram plot of the image
  • the imexamine-like tool shall implement a feature to generate a radially averaged profile plot of the image with the origin specified by the cursor location.
  • the imexamine-like tool shall implement a feature to display the coordinates of the cursor in both pixel coordinates and world coordinates
  • the imexamine-like tool shall implement a feature to display the total flux within an aperture centered on the cursor position. The details of the aperture (e.g., shape, size) used are selected by parameters to the tool.
  • the imexamine-like tool shall implement a feature to fit a 2-d Gaussian to the feature within a specified radius of the cursor.
  • the imexamine-like tool shall implement a feature to compute statistics on a user-selected region of the image.
  • the imexamine-like tool shall implement a feature to print the image values in a user-selected region of the image.
  • the imexamine-like tool shall implement the ability to support a graphics cursor mode that can annotate the image, expanding or roaming, or print cursor positions
Last modified 5 years ago Last modified on 03/06/14 15:10:47