InterForm400 support AFPDS spooled files as input. AFPDS spooled files can e.g. be used, if you want to use real unicode spooled files for InterForm400.
The text contents of the AFPDS spooled file is converted into a text based file before processing, so any special fonts, barcodes or images included in the input spooled file are lost, but you can add them again in the InterForm400 designer.
If you want to use unicode input spooled file, then AFPDS spooled files are recommended. An example is included here.