.. _rascil_apps_imaging_qa:

.. py:currentmodule:: rascil.apps

imaging_qa
==========

.. note::

    As of RASCIL 2.0.0, imaging_qa is no longer available from this package.
    Instead, refer to its stand-alone distribution at
    https://gitlab.com/ska-telescope/sdp/ska-sdp-continuum-imaging-qa

imaging_qa is a command line app written using RASCIL.
It uses the python package `PyBDSF <https://github.com/lofar-astron/PyBDSF.git>`_ to find sources in an image
and check with the original inputs. Currently it features the following:

  - Reads FITS images.
  - Finds sources above a certain threshold and outputs the catalogue (in CSV, FITS and skycomponents format). For multi-frequency images, the source detection can be performed on the central channel or average over all channels. 
  - Produces image statistics and diagnostic plots including: running mean plots of the residual, restored, background and sources and a histogram with fitted Gaussian and power spectrum of the residual are also plotted.
  - Optional: Read in the sensitivity image and apply a primary beam correction to the fluxes.
  - Optional: Estimate the spectral index by reading in frequency moment images (in FITS format) containing higher order Taylor terms.
  - Optional: compares with input source catalogue : takes hdf5 and txt format. The source input should has columns of "RA(deg), Dec(deg), FluxI(Jy), FluxQ(Jy), FluxU(Jy), FluxV(Jy), Ref. Freq.(Hz), Spectral Index".
  - Optional: plot the comparison and error of positions and fluxes for input and output source catalogue.