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1. Re: PDF CID keyed font support
lrosenth Nov 10, 2014 4:08 AM (in response to JamieLaManger)You can only use CFF-based Type 1 fonts for CID, since a classic Type 1 didn’t know anything about Unicode.
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2. Re: PDF CID keyed font support
JamieLaManger Nov 10, 2014 5:35 AM (in response to lrosenth)thanks for the reply, but I don't quite understand your answer.
Could you explain to me how the Unicode issue affects and explains your assertion that only CFF is supported?
My understanding is that a composite font in PDF has to use a CMap to generate a numeric CID, the problem with a type 1 font would then be that glyphs are selected by name - how do you
map a CID to a glyph name?
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3. Re: PDF CID keyed font support
lrosenth Nov 10, 2014 5:44 AM (in response to JamieLaManger)You don’t.
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4. Re: PDF CID keyed font support
JamieLaManger Nov 10, 2014 6:05 AM (in response to lrosenth)ok, let me rephrase my question a little.
please explain why the fact that a type1 font doesn't know about Unicode means that a CID keyed font has to use a CFF embedded font program rather than, for instance, a CIDFont that uses a type 1 font program.
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5. Re: PDF CID keyed font support
JamieLaManger Nov 10, 2014 6:14 AM (in response to lrosenth)can I add a little background to my question.
We have a print language conversion application that can receive fonts from a variety of sources.
One such source will generate CIDFonts that contains type 1 font programs and these are perfectly valid, they can be rendered by the FreeType library etc.
however, if transforming a print stream to PDF, I am worried that PDF cannot represent such a thing (non CFF, CID keyed).
If I know that this is the case, then I know that we have the big problem of Type1 to CFF conversion in order to embed the font in pDF.
This is what has prompted my question.
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6. Re: PDF CID keyed font support
lrosenth Nov 10, 2014 6:22 AM (in response to JamieLaManger)ISO 32000-1:2008 (aka the PDF standard) is very clear on the topic:
9.7.4.1 General
A CIDFont program contains glyph descriptions that are accessed using a CID as the character selector. There
are two types of CIDFonts:
• A Type 0 CIDFont contains glyph descriptions based on CFF
NOTE The term “Type 0” when applied to a CIDFont has a different meaning than for a “Type 0 font”.
• A Type 2 CIDFont contains glyph descriptions based on the TrueType font format
I am confused, however what print language you are converting to PDF that has a CIDFont, since that is a PDF-centric concept.
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7. Re: PDF CID keyed font support
JamieLaManger Nov 10, 2014 6:35 AM (in response to lrosenth)I thought CIDFonts existed in the PS world well before PDF, and also, in the PS world, CIDFonts are more complex because they aren't limited to a single descendent font.
My understanding of the PDF spec is that a composite font has only 1 descendant unlike in PS. But that's a bit off topic.
AFP (a nasty old IBM transactional print language) will generate CIDFonts which use type1 font (not CFF) as a descendent - these CIDfonts are handled by FreeType.
the problem I have is how to embed them in PDF (when converting the AFP stream to PDF).
The bit you quote from the ISo standard is really clear, I agree, I had been using the PDF reference manual which doesn't specify CFF for composite based in type1, it says:
"•A Type 0 CIDFont contains glyph descriptions based on the Adobe Type 1 font format"
based on the ISO spec and what you tell me, I guess it is clear that you cannot represent a CIDFont which is based on a non-CFF font program in a PDF file unless you convert the Type1 font to CFF. Is that right?
Thanks
AFO
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8. Re: PDF CID keyed font support
lrosenth Nov 10, 2014 7:22 AM (in response to JamieLaManger)ISO Standard is the document you should be using – it supersedes all of the Adobe references.
Correct. You need to convert the T1->CFF for use in a CIDFont.
(and yes, PS also did CIDFonts of more complexity)
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9. Re: PDF CID keyed font support
JamieLaManger Nov 10, 2014 12:28 PM (in response to lrosenth)thanks ever so much for the info.
One last thing - I said earlier that I thought I had examples of CIDFonts that had non CFF data, I think I may well have got that wrong.
To your knowledge, does the CIDFont spec support type 1 charstrings (like you find in type 1 fonts)?


