# Are Knuth's fonts searchable in pdf yet?

Donald Knuth at the Desktop Publishing Pioneers meeting laments that converting to pdf using his fonts yields pdf files without searchable text. Is this fixed yet?

https://youtu.be/WVRMPihnZZM?t=4363

• Thanks for posting that link. The fonts that Knuth is asking about are explicitly Type 3. Regarding whether a PDF file containing Type 3 fonts is searchable yet, my guess is that it is not. Type 3 fonts are by definition bitmaps and bitmaps can contain anything, so I don't see much enthusiasm there from the "industry" to make it happen. (I suspect it could be done by post-processing by a good OCR scanner.) If you watch the rest of the video, it's clear that everyone else is talking about the mass market. Mathematics remains "penalty copy". – barbara beeton May 21 at 22:42
• Not exactly, the Type 3 font is a user defined font, but it's not a requirement to use bitmaps and most Type 3 fonts are probably vector. The effect is the same that they can contain anything. But at heart it's still a font so the thing has a fundamental purpose to map letters and numbers (in some encoding) to the shapes that visually represent them. Somehow these fonts forget this mapping, and that smells like some stupid happened somewhere. – luser droog May 22 at 9:20
• Thanks for the correction/clarification. – barbara beeton May 22 at 15:06
• Type 3 may not have a requirement to use bitmaps, but as @barbarabeeton says, it's a requirement for Knuth to use bitmaps as he wants control of the rasterization. Anyway, going by section 9.10 ("Extraction of Text Content") of the PDF 1.7 standard, it does not seem to be fundamentally impossible... the font dictionary would just need an Encoding dictionary or ToUnicode CMap, both of which are supported for Type 3 fonts (see 9.6.5 "Type 3 Fonts", Table 112 on p. 259). Missing feature in pdfTeX, maybe? – ShreevatsaR May 23 at 22:20

• Since it's Knuth asking, this isn't an option for him. Some of the shapes in Latin Modern (e.g. the \ss) are noticeably different, and Knuth explicitly said he wants to keep using fonts that are under his control. Also, Knuth does not and will not use LaTeX. – barbara beeton May 22 at 15:08