December 2017 - ntg-pdftex - NTG Mailing Lists

Incomplete CharSet causes failure with PDF/A validation
by Ross Moore 29 Jan '19

29 Jan '19

Hi all. I believe there is a problem with the way pdfTeX constructs the CharSet for a subsetted font. Not all fonts are affected, and it only shows up when attempting to validate for PDF/A. I’ve mentioned the problem to Thanh and others, but as there’s been nothing done, I’ll bring it up here, with an example that cannot be worked-around. Attached are two PDF/A documents, using Hebrew text. The main font is the “David” style font from the culmus package: DavidCLM-Medium hebart-david.pdf — produced by pdfTeX hebart-gs.pdf — produced using dvips+GS hebart-david fails PDF/A validation in one aspect only (see image): “CharSet in subset font is incomplete (font contains glyphs that are not listed)"

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[PATCH v4] Allow .enc files for bitmap PK fonts
by Pali Rohár 02 Jan '18

02 Jan '18

Hi! I'm sending new series of patches for PK fonts which are reworked on top of current texlive trunk svn repository. I split changes into more patch files and updated also documentation with test. Karl, can you look at them? -- Pali Rohár pali.rohar(a)gmail.com

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Using CFF (Type 1C) instead of Type 1 fonts
by Markus Kuhn 19 Dec '17

19 Dec '17

PDFs produced by pdftex can shrink significantly in size when processed through ghostscript's pdfwrite driver. I understand a main reason for that is that ghostscript converts any Type 1 fonts that it finds into CFF (aka Type 1C) fonts. I also understand that - Type 1 fonts are eexec-encrypted, and such ciphertext cannot benefit from PDF's (de)flate compression. - CFF fonts, on the other hand, are a compacter plain-text format and compress well. - CFF fonts are also compatible with Type1, i.e. it is possible to convert any Type 1 font into a CFF font without loss of information. Is all of this correct? If so, isn't the continued use of Type 1 fonts in the TeX ecosystem an anachronism? Shouldn't TeXLive ship instead CFF/Type 1C versions of the BlueSky Computer Modern fonts and shouldn't tools like pdftex switch to using them directly? Has someone looked into what would be involved with a Type 1 to CFF migration for pdftex? It seems at the moment, pdftex is actually replacing any Type 1C glyphs that it finds in a PDF file embedded with \pdfximage with the much less space-efficient Type 1 glyphs that it find in its font map files. Has there been any progress on this since: https://tex.stackexchange.com/questions/38145/why-does-pdflatex-produce-big… ? Markus -- Markus Kuhn, Computer Laboratory, University of Cambridge http://www.cl.cam.ac.uk/~mgk25/ || CB3 0FD, Great Britain

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