Cidfont+f1 F2 F3 F4 F5 F6 ((top)) «360p»

This is an excellent and highly technical topic. The notation cidfont+f1 , cidfont+f2 , etc., is specific to and PDF internals, usually observed in PDF stream dumps , PostScript printer logs , or extracted font debugging output .

Would you like a Python script example that iterates through all CIDFont subsets in a PDF and reports their original font names and glyph counts? cidfont+f1 f2 f3 f4 f5 f6

If you are working on a specific PDF with f1…f6 and need to reduce or analyze them, tools like cpdf (Coherent PDF), hexaPDF (Ruby), or pymupdf (Python) give programmatic control. This is an excellent and highly technical topic

Example simplified PDF object: