Your HiPS step by step

1. Download the latest version of Aladin/Hipsgen code. Do not hesitate to use the last beta version:
   → AladinBeta.jar
   Note: You can also use Hipsgen.jar package, but it is more useful to use directly Aladin for generating & checking the HiPS with the same tool (and concretely, it is the same code).
2. Set together the collection of the original images or cubes in a local directory (sub-directory hierarchy is allowed, symbolic links can be useful, gzipped ou FITS compressed images (rice, ...) are allowed)
   → we assume "Data" directory
   Note: There is no limit (image size and/or number of images) apart your disk.
3. Optional: Load one image in Aladin to be sure that its astrometrical calibration is correctly interpreted and to determine the HiPS generation parameters:
   → java -Xmx2g -jar AladinBeta.jar Data/OneImage.fits
   • If your images are packaged in Multi-Extension FITS, memorize the index of the good HDU or possibly all HDUs for multi-CCD packaging (cf. hdu parameter)
   • Adjust the contrast and memorize the pixel min & pixel max display value (Ctrl+M: left and right values over the pixel histogram) (cf. pixelCut parameter)
   • Check if the borders of your images are ok, or if you have to remove a margin, and/or if the borders of image have not been observed -typically filled up with 0 (cf. blank parameter), or if your observations are circular (cf. shape parameter).
   • Look in the FITS header (Alt+H) which additionnal keywords could be kept as meta data information for progenitor facility (see below), for instance: DATE-OBS, INSTRUM, EXP_TIME, ... (cf. fitsKey parameter)
4. Optional: Create a "pilot" HiPS on few images for a quick test:
   • Launch the Pilot HiPS creation on the first 100 images by this script command:
     → java -Xmx16g -jar AladinBeta.jar -hipsgen in=Data out=PilotHiPS id=HiPSID pilot=100
   • Check the resulting HiPS thanks to Aladin:
     → java -jar AladinBeta.jar PilotHiPS
   • If required, reiterate the HiPS computation by inserting/modifying these Hipsgen parameters: blank, border, fov, skyval, pixelCut, fmode, partitioning... - see the manual below.
     Do not forget to insert "-clean" option for removing the previous HiPS (or remove it manually).
5. Launch the HiPS creation on all original data.
   Take care that this process can be long and very computer consuming (RAM and CPU). You can adjust the RAM by the java -XmxNNg parameter, and the number of threads by the maxThread Hipsgen parameter. The final HiPS size can be estimated to 1.3x of the original size of data.
   → java -Xmx16g -jar AladinBeta.jar -hipsgen maxThread=20 in=Data ...
6. Check the result thanks to Aladin Desktop and/or via Aladin Lite
   → Aladin Desktop: java -jar AladinBeta.jar DataHiPS
   → Aladin Lite: in your browser, load the directory DataHiPS
7. Complete the description of your HiPS by editing the file DataHiPS/properties (read the inside comments). Do not forget to provide a creator_did identifier for your HiPS. The syntax follows the IVOA IVOID recommendation (ivo://XXX/...). The first word MUST be the acronym of your institute (CDS, IAS, ESAC, STScI, ...) and your HiPS - or atleast your institute - should be declared in the IVOA VO registry (see point 10).
8. Distribute your HiPS by serving or moving your DataHiPS directory thanks to a basic httpd server (apache...).
   No data base software or CGI are required, just a HTTP access to the HiPS directory.
9. Optional: Add your HiPS in Aladin and/or other HiPS aware clients.
   For that, you need to declare your "HiPS server" and become by this way a member of the "HiPS network".
   • Become a official HiPS server by just generating and publishing your hips list. The HiPS list is basically the concatenation of all the properties files of your HiPS. You can do that manually, or via a CGI script like this one (cf HiPS IVOA doc - section 5, page 22)
   • Declare your HiPS server in the VO registry (see IVOA document section 5.3.1 page 24). In parallel, you can contact the CDS which temporary maintains the list of HiPS servers.
   • Check if your HiPS is now visible in the HiPS clients of your choice. If it is not the case, contact directly the HiPS clients developers (CDS for Aladin Desktop or Aladin Lite). For your help, the CDS maintains this HiPS table which is aggregating all declared HiPS lists.
10. Optional: Declare your individual HiPS in the VO registry
    (see IVOA document - section 5.3.2 page 25)