[PDFBOX-5868] PDFBox not extracting text of non-latin languages(tamil, bengali) properly but adobe reader's save as text does

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.0.32, 3.0.3 PDFBox
• Fix Version/s: 2.0.33, 3.0.4 PDFBox, 4.0.0
• Component/s: Text extraction
• Labels: ActualText
• Environment: Ubuntu 22.04.4 LTS x86_64
• Assignee: Tilman Hausherr
• Reporter: Manish S N
• Created: 14/Aug/24 07:33
• Updated: 30/Aug/24 12:43

Description

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:

1. why are the outputs from pdfbox and adobe different?
2. what can i do to extract the text from a multilingual pdf correctly?
3. 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)

 

Issue Links

• duplicates: PDFBOX-3248 Unwanted spaces in text extraction (2)
• is duplicated by: PDFBOX-4532 PDFTextStripper replacing the decimal with white space
• is duplicated by: TIKA-4231 Parsing Arabic PDF is returning bad data