FITS works in different stages as shown in the image below.
The steps are described in more detail here.
- First the configuration files are read. This determines which tools are called and can affect the output.
- Each tool (JHOVE etc.) is called in parallel to process the file or directory of files (depending on the option used). Each tool's native output is converted to FITS XML.
- All of the FITS XML is consolidated into a single instance of FITS XML.
- The FITS XML is converted to standard XML (e.g. MIX) (if this option was requested for example by using the -x parameter on the command line).
For a more technical description of FITS processing - see the technical description in the Developer Manual.