FITS Army Knife

Contains a FITS/XISF file viewer implemented using the cftisio library, PixInsight Class Library (PCL) and Qt. Qt should enable cross-platform support, but I have only built and run on linux so far.

It is unlikely I would have achieved success without this code example. The cfitsio documention does not really make things obvious. So, thank you Mitch Richling!

There are times when I would just like to quickly take a look at a FITS or XISF image, and I have not yet found a simple tool for this. This project will become such a tool.

Current features:

• FITS support
• XISF support
• Zoom with scroll wheel
  • Image position under mouse pointer is maintained (i.e., zoom what is pointed at)
  • Buttons for 1:1 and zoom-to-fit
• Drag image position
• Histogram
• Pixel Statistics (min/mean/median/max)
• Integrated screen transfer function
  • From PixInsight Reference Documentation
• Multi-file support
  • First invocation shows user interface, subsequent invocations exit after passing arguments to running instance (adding files to its list)
  • At least one file or folder must be given on first invocation
  • Subsequent invocations can add files and/or folders using same syntax as first invocation
  • Implemented using QSockets for platform independence

Feature ideas:

• Quick option to see center and corners at 1:1
• Option to highlight the brightest and/or darkest pixels
• Histogram refinements?

Those are the key ones, and some nice to haves:

• Ability to scroll through many images
  • Keep zoom/position the same
• Easy and quick Pick/Reject function
• Ability to watch a directory and automatically keep loading files as they show up
• Support for DSLR raw files? Not sure how hard (i.e., proprietary) that is yet
• Possible live stack? Depending on if I can figure out the math...

Dependencies

You will need Qt5, the cfitsio library, and the PixInsight Class Library (PCL).

On debian based linux systems:

sudo apt install qt5-default for Qt

sudo apt install libcfitsio-dev for cfitsio

On arch linux systems:

sudo pacman -S qt5-base for Qt

sudo pacman -S qt5-doc for Qt documentation (optional)

sudo pacman -S cfitsio for cfitsio

PCL must be downloaded from GitLab and built from source.

You will also need some FITS/XISF files to test with.

Building PCL

Define environment variables needed by PCL. These are:

• PCLDIR - Set to the directory where you extracted PCL
• PCLINCDIR - ${PCLDIR}/include
• PCLSRCDIR - ${PCLDIR}/src
• PCLBINDIR - ${PCLDIR}/bin
• PCLBINDIR64 - ${PCLBINDIR}
• PCLLIBDIR - ${PCLDIR}/lib/linux/x64
• PCLLIBDIR64 - ${PCLLIBDIR}

Navigate to ${PCLDIR}/src/pcl/linux/g++.

make

(The version of PCL I downloaded [2021-Aug-18] did not build for me due to references to cuda.h. I believe that is for accelerated NVIDIA. I removed the one file that referenced this [CUDADevice.cpp] from the makefile and it then built without any ill effects that I have discovered yet.)

Verify that the libraries libPCL-pxi.a and libRFC6234-pxi.a exist in ${PCLLIBDIR}.

Building

Please note that this project only builds under Linux for now

Define PCL environment variables as above.

Create a directory called "build" (or whatever you like, really, but build is already git ignored) in the root directory of the project.

Change to the build directory and execute qmake ..

You will now have a Makefile. Run make

You should now have an executable, unless you are missing a dependency somewhere. To run:

./fits-army-knife <path-to-fits-or-xisf-file>

or

./fits-army-knife <path-to-dir-containing-fits-or-xisf-files>