在 Ubuntu 上，如果我尝试查看此 pdf： https://gradschool.princeton.edu/sites/gradschool/files/FPO_Examination_Report.pdf
一切都进展顺利除了第二行（包含“已提交论文，如前所述”的行）。在这一行的开头，在文本框之前，只有一堆相互重叠的垃圾字符。
问题似乎是 Calibri 字体未嵌入。
以下是一些可能有用的输出：
$ pdffonts FPO_Examination_Report.pdf
name type encoding emb sub uni object ID
------------------------------------ ----------------- ---------------- --- --- --- ---------
Calibri CID TrueType Identity-H no no no 78 0
BUOFXG+Calibri CID TrueType Identity-H yes yes yes 83 0
HCQTDJ+Calibri TrueType WinAnsi yes yes yes 85 0
HCQTDJ+Calibri-Bold TrueType WinAnsi yes yes yes 87 0
HCQTDJ+Calibri-Italic TrueType WinAnsi yes yes yes 89 0
$ pdffonts -subst FPO_Examination_Report.pdf
name object ID substitute font substitute font file
------------------------------------ --------- ------------------------------------ ------------------------------------
Calibri 78 0 Carlito /usr/share/fonts/truetype/crosextra/Carlito-Regular.ttf
$
$ /usr/bin/gs \
> -o testing.pdf \
> -dPDFSETTINGS=/prepress \
> -sDEVICE=pdfwrite \
> FPO_Examination_Report.pdf
GPL Ghostscript 9.15 (2014-09-22)
Copyright (C) 2014 Artifex Software, Inc. All rights reserved.
This software comes with NO WARRANTY: see the file PUBLIC for details.
Processing pages 1 through 1.
Page 1
Can't find CID font "Calibri".
Attempting to substitute CID font /Adobe-Identity for /Calibri, see doc/Use.htm#CIDFontSubstitution.
The substitute CID font "Adobe-Identity" is not provided either. attempting to use fallback CIDFont.See doc/Use.htm#CIDFontSubstitution.
Loading a TT font from /usr/share/ghostscript/9.15/Resource/CIDFSubst/DroidSansFallback.ttf to emulate a CID font Adobe-Identity ... Done.
Can't find CMap Identity-UTF16-H building a CIDDecoding resource.
Warning: falling back to Identity ordering
Loading a TT font from /usr/share/ghostscript/9.15/Resource/CIDFSubst/DroidSansFallback.ttf to emulate a CID font CIDFallBack ... Done.
Can't find CMap Identity-UTF16-H building a CIDDecoding resource.
**** Warning: can't process font stream, loading font by the name.
Can't find CID font "Calibri".
Attempting to substitute CID font /Adobe-Identity for /Calibri, see doc/Use.htm#CIDFontSubstitution.
The substitute CID font "Adobe-Identity" is not provided either. attempting to use fallback CIDFont.See doc/Use.htm#CIDFontSubstitution.
Loading a TT font from /usr/share/ghostscript/9.15/Resource/CIDFSubst/DroidSansFallback.ttf to emulate a CID font Adobe-Identity ... Done.
Can't find CMap Identity-UTF16-H building a CIDDecoding resource.
Warning: falling back to Identity ordering
Loading a TT font from /usr/share/ghostscript/9.15/Resource/CIDFSubst/DroidSansFallback.ttf to emulate a CID font CIDFallBack ... Done.
Can't find CMap Identity-UTF16-H building a CIDDecoding resource.
**** Error reading a content stream. The page may be incomplete.
**** File did not complete the page properly and may be damaged.
**** This file had errors that were repaired or ignored.
**** The file was produced by:
**** >>>> Adobe PDF Library 9.0 <<<<
**** Please notify the author of the software that produced this
**** file that it does not conform to Adobe's published PDF
**** specification.
$