You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@pdfbox.apache.org by "Andreas Lehmkühler (Jira)" <ji...@apache.org> on 2020/07/04 13:53:00 UTC
[jira] [Comment Edited] (PDFBOX-4896) Don't save and restore
graphic states around showGlyph in LegacyPDFStreamEngine
[ https://issues.apache.org/jira/browse/PDFBOX-4896?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17151335#comment-17151335 ]
Andreas Lehmkühler edited comment on PDFBOX-4896 at 7/4/20, 1:53 PM:
---------------------------------------------------------------------
I've removed the saving of the text and text line matrix as well. It wasn't needed either.
[~tilman] Thanks for double checking.
[~Faltiska] Thanks again for reporting
was (Author: lehmi):
[~tilman] Thanks for double checking.
[~Faltiska] Thanks again for reporting
> Don't save and restore graphic states around showGlyph in LegacyPDFStreamEngine
> -------------------------------------------------------------------------------
>
> Key: PDFBOX-4896
> URL: https://issues.apache.org/jira/browse/PDFBOX-4896
> Project: PDFBox
> Issue Type: Improvement
> Components: Text extraction
> Affects Versions: 2.0.20, 3.0.0 PDFBox
> Reporter: Alfred
> Assignee: Andreas Lehmkühler
> Priority: Minor
> Labels: Optimization
> Fix For: 2.0.21, 3.0.0 PDFBox
>
> Attachments: PDFBOX-4896.patch
>
>
> One of the major performance bottlenecks in text extraction was the
> clone + push and the pop + clone operations on the graphic state before and after the call to showGlyph.
> Not only it was slow to clone, it also consumes large amounts of memory making the garbage collector work harder.
> When extracting text, showGlyph does not modify the graphic state so there's no need to save / restore the state.
> The same could be true in general, not just for text extraction, but I do not understand the code well enough to decide.
> I have only modified the behavior for the LegacyPDFStreamEngine, to be safe.
> The showGlyph operation sounds like a read only operation, that should not modify anything.
>
> I have the code ready and I will submit a patch and a review.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@pdfbox.apache.org
For additional commands, e-mail: dev-help@pdfbox.apache.org