[
https://issues.apache.org/jira/browse/PDFBOX-5868?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17874700#comment-17874700
]
Tilman Hausherr commented on PDFBOX-5868:
-----------------------------------------
I ran a comparison on several 100000 PDF files. While there were many
improvements, I discovered that /ActualText is also used to PREVENT text
extraction, as shown by these files:
[^PDFBOX-5868-7FHMU2HNOUUPENUPKZDGD2V65YEVABRS-EmptyActualText.pdf]
[^PDFBOX-5868-SI5K4X4Z55SQAUPLAUP6QRRWT3UD3LAA-EmptyActualText.pdf]
[^PDFBOX-5868-SI5K4X4Z55SQAUPLAUP6QRRWT3UD3LAA-EmptyActualText_reduced.pdf]
> PDFBox not extracting text of non-latin languages(tamil, bengali) properly
> but adobe reader's save as text does
> ---------------------------------------------------------------------------------------------------------------
>
> Key: PDFBOX-5868
> URL: https://issues.apache.org/jira/browse/PDFBOX-5868
> Project: PDFBox
> Issue Type: Bug
> Components: Text extraction
> Affects Versions: 2.0.32, 3.0.3 PDFBox
> Environment: Ubuntu 22.04.4 LTS x86_64
> Reporter: Manish S N
> Assignee: Tilman Hausherr
> Priority: Major
> Labels: ActualText
> Fix For: 2.0.33, 3.0.4 PDFBox, 4.0.0
>
> Attachments: Main.java,
> PDFBOX-5868-7FHMU2HNOUUPENUPKZDGD2V65YEVABRS-EmptyActualText.pdf,
> PDFBOX-5868-SI5K4X4Z55SQAUPLAUP6QRRWT3UD3LAA-EmptyActualText.pdf,
> PDFBOX-5868-SI5K4X4Z55SQAUPLAUP6QRRWT3UD3LAA-EmptyActualText_reduced.pdf,
> Tilman's_solution_out.txt, adobe_out.txt, multilingual_test.pdf,
> okular_out.txt, pdfbox_out.txt, poppler_out.txt, screenshot-1.png,
> screenshot-2.png, suppressDuplicateOverlapping_out.txt
>
>
> I downloaded the latest executable jar of pdfbox (3.0.3) for testing and used
> the export:text command line tool to obtain the results
> * the multilingual_test.pdf is the original pdf i made to test multilingual
> text extraction.
> * the pdfbox_out.txt is the text file produced by pdfbox
> * the adobe_out.txt is the text file created by adobe reader's save as text
> feature
>
> Observation:
> as you can see in the attachment the text file obtained by pdfbox shows weird
> unicodes for tamil and bengali (for hindi the charecters are extracted but
> not overlapped; japanese seems fine to me). in contrast the text file file
> obtained from adobe reader's save as text feature seems fine and copy pasting
> the text from my document viewer(evince) also works.
> Questions:
> # why are the outputs from pdfbox and adobe different?
> # what can i do to extract the text from a multilingual pdf correctly?
> # Is there a way to apply pattern matching to text in pdf file and declare
> matches without extracting the text first? (say if the problem is with fonts
> and glyphs)
> —
> My Usecase fyi:
> i am trying to extract text from files and run pattern matching. I am using
> apache tika for parsing documents. I noticed problem with extracted PDF text
> (other filetypes parse fine). used executable pdfbox jar to conclude that the
> _problem is in pdfbox and not in tika._ tested with adobe reader's extract
> text to confirm the problem is not with the pdf. i want to extract these
> multilingual text to run pattern matching on them alone and do not need to
> display the content but only if the pattern is present or not (say if the
> problem is with fonts and glyphs)
>
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@pdfbox.apache.org
For additional commands, e-mail: dev-h...@pdfbox.apache.org
