List all fonts in a PDF, showing if they are CID and their internal names:
pdffonts document.pdf
Output example:
name type encoding emb sub uni object ID
----------------- ------------ ------------ --- --- --- ---------
F1 CID Type0 Identity-H yes yes yes 7 0
F2 CID Type2 Identity-V yes yes yes 10 0
The F1 tag is a dictionary key inside the PDF’s structure. When the PDF reader wants to draw text, it looks for the object labeled /F1, finds the embedded font dictionary, and then uses the CMap to render the character. cid font f1 f2 f3 f4
This abstraction allows the PDF to remain small and efficient. The actual font name (PostScript name) is stored one level deeper, inside the CIDFont dictionary. List all fonts in a PDF, showing if
Why it happens: The PDF was created without embedding the actual CID font data. It only stored a reference to F1. When you open it on a system without that specific Japanese/Chinese font, the reader panics.
Solution: Use Acrobat Pro to embed the font. Go to Print Production > Preflight > Fixups > Embed missing fonts. Output example: name type encoding emb sub uni