[
https://issues.apache.org/jira/browse/PDFBOX-4793?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17052195#comment-17052195
]
Tilman Hausherr edited comment on PDFBOX-4793 at 3/5/20, 2:46 PM:
------------------------------------------------------------------
Of course it is a bad decision... my idea, maybe a year ago (probably my pc
crashed so I lost that open window in my IDE and forgot about the problem), was
to set "blacklist rules".
This font is a Korean font. WTF would this ever be acceptable as a match.
isCharSetMatch() should avoid this.
However it returns true because it hits this part
{code}
if (cidSystemInfo.getOrdering().equals("GB1") &&
(codePageRange & CHINESE_SIMPLIFIED) == CHINESE_SIMPLIFIED)
{
return true;
}
{code}
codePageRange is
-2882585235952893507 which is
D7FF 0000 203E 01BD
According to DTL OTMaster 3.7 light, ulUnicodeRange1 is 0x900002af and
ulUnicodeRange2 is 0x01d77cfb.
According to the debugger, ours are 0x203e01bd and 0xd7ff0000.
More to investigate...
was (Author: tilman):
Of course it is a bad decision... my idea, maybe a year ago (probably my pc
crashed so I lost that open window in my IDE and forgot about the problem), was
to set "blacklist rules".
This font is a Korean font. WTF would this ever be acceptable as a match.
isCharSetMatch() should avoid this.
However it returns true because it hits this part
{code}
if (cidSystemInfo.getOrdering().equals("GB1") &&
(codePageRange & CHINESE_SIMPLIFIED) == CHINESE_SIMPLIFIED)
{
return true;
}
{code}
codePageRange is
-2882585235952893507 which is
D7FF 0000 203E 01BD
According to DTL OTMaster 3.7 light, ulUnicodeRange1 is 0x900002af and
ulUnicodeRange2 is 0x01d77cfb.
More to investigate...
> Questionable fallback font for some embedded chinese fonts
> ----------------------------------------------------------
>
> Key: PDFBOX-4793
> URL: https://issues.apache.org/jira/browse/PDFBOX-4793
> Project: PDFBox
> Issue Type: Bug
> Components: Rendering
> Affects Versions: 2.0.18
> Reporter: Christian Appl
> Priority: Major
> Attachments: PDFJS-10699.pdf, image-2020-03-04-09-49-42-323.png,
> image-2020-03-04-09-58-01-055.png, image-2020-03-04-10-09-25-343.png,
> image-2020-03-04-10-31-03-065.png, pdf_font-zhcn.pdf, screenshot-2.png,
> screenshot-3.png, screenshot-4.png, screenshot-5.png, screenshot-6.png
>
>
> *Issue:*
> I tried to render PDFs, that contain embedded chinese fonts. Neither the PDF
> Debugger, nor printouts of the document (PDFPrintable), nor the PDFRenderer
> can display/render the chinese glyphs correctly and will render placeholders
> instead.
> *Assumptions:*
> I assume, that said embedded fonts are incomplete and don't contain all
> glyphs, that would be required to render the text properly and therefore
> PDFbox attempts to use the previously determined fallback font. (!?)
> !image-2020-03-04-09-49-42-323.png!
> !image-2020-03-04-09-58-01-055.png!
> And fails to find the glyphs in said fallback font.
> Which is not surprising, as the Fallback font "MalgunGothic-Semilight"
> (Windows standard font) does not contain chinese characters.
> !image-2020-03-04-10-09-25-343.png!
> *Debugging:*
> I tried to understand how the fallback font is determined and what could be
> done to solve this problem on my end. But I was unable to find a satisfying
> solution.
> My best guess so far is, that the CIDFontMapping (FontMapperImpl) is to blame
> for determining an unfit fallback font.
> Although it seems to check, whether required codepages are contained in a
> fallback font, it still does rank the Malgun font as the topscorer and best
> substitute font, even though it does clearly not contain all required
> codepages.
> *My opinion:*
> This is troubling, as better fit fonts exist and could have been selected.
> (ie.: Adobe Stong Std) And are indeed included in the CIDFontMapping, but
> seemingly are scoring lower for some reason.
> *Further information:*
> I can not disclose the document in question, however I found a document
> (pdf_font-zhcn.pdf) in another issue (PDFBOX-3132), that can be used to
> reproduce the issue (ie.: by dropping it into the PDF Debugger)
> !image-2020-03-04-10-31-03-065.png!
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
