Zitat von Rodrigo Caniçali <[email protected]>:

Hi Thomas,

There is no such object at the whole document. Looking for the keyword "/XRef" or "80 0", the editor cannot find them
The 80 0 was an example. If you can't find the /XRef it means there is no xref stream, only the xref table. The table looks invalid at the first look. Normally the objects should be sorted so the first object need to appear first in the document and the second as the next object. So correctly the offsets for the objects should be go from small to large numbers. In your document the objects seems to be shuffled. I haven't see such a document since I'm working with pdfs. For me the file is completely broken. Maybe the file was previously merged or something else, so the structure broke, I have no idea.

There is no way for pdfbox parsing such files and I can't imagine that we will be able to parse it in the future.

Sry that I could not help you with this one.

Best regards
Thomas

anywhere. However I could find at the end of the document the following code:

xref
0 47
0000000000 65535 f 
0000000009 00000 n 
0000052584 00000 n 
0000052633 00000 n 
0000009275 00000 n 
0000000199 00000 n 
0000003543 00000 n 
....
0000052345 0000 n 

trailer
<<

/Size 47
/Root 2 0 R
/Info 1 0 R

startxref
52279
%%EOF

Changing the reference 52279 by 53730 which is the address of "xref", it seems that the xref table position error has been solved. 

But the following warning is still been displayed and some text are still not been extracted:

Loading PDF D:\Documents and Settings\05215385726\rpf_tributos.pdf
Time for loading: 0.094 seconds
Starting text extraction
Writing to D:\Documents and Settings\05215385726\rpf_tributos.txt
Nov 14, 2013 11:24:36 AM org.apache.pdfbox.util.PDFStreamEngine processOperator
INFO: unsupported/disabled operation: o
Nov 14, 2013 11:24:36 AM org.apache.pdfbox.util.PDFStreamEngine processOperator
INFO: unsupported/disabled operation: Os
Nov 14, 2013 11:24:36 AM org.apache.pdfbox.util.PDFStreamEngine processOperator
INFO: unsupported/disabled operation: a
Nov 14, 2013 11:24:36 AM org.apache.pdfbox.util.PDFStreamEngine processOperator
INFO: unsupported/disabled operation: su


Also, with the "-nonSeq" option enabled, the error below is displayed:

Loading PDF D:\Documents and Settings\05215385726\Meus documentos\rpf_tributos.pdf Exception in thread "main" java.io.IOException: Error: Expected a long type, actual='K`_'
at org.apache.pdfbox.pdfparser.BaseParser.readLong(BaseParser.java:1668)
at org.apache.pdfbox.pdfparser.BaseParser.readObjectNumber(BaseParser.java:1598) at org.apache.pdfbox.pdfparser.NonSequentialPDFParser.parseObjectDynamically(NonSequentialPDFParser.java:1183) at org.apache.pdfbox.pdfparser.NonSequentialPDFParser.parseObjectDynamically(NonSequentialPDFParser.java:1130) at org.apache.pdfbox.pdfparser.NonSequentialPDFParser.initialParse(NonSequentialPDFParser.java:420) at org.apache.pdfbox.pdfparser.NonSequentialPDFParser.parse(NonSequentialPDFParser.java:702)
at org.apache.pdfbox.pdmodel.PDDocument.loadNonSeq(PDDocument.java:1139)
at org.apache.pdfbox.ExtractText.startExtraction(ExtractText.java:208)
at org.apache.pdfbox.ExtractText.main(ExtractText.java:85)


I wonder if I could write a routine to fix a document like this before parsing it with PDFbox, since it can be parsed by Acrobat Reader.

Thanks,

Rodrigo



Em Quarta-feira, 13 de Novembro de 2013 19:49, Thomas Chojecki <[email protected]> escreveu:

Hi Rodrigo,
it look like the startxref position (52779) is wrong and point into a 
stream instead at the beginning of a xref table or stream. The value 
inside the exception shows a compressed string and it might be the 
xref stream.

You can open a hex editor and jump directly to the position 52779 and 
look for a object that may look like

,---

80 0 obj <<
/Type /XRef
/Index [0 424]
/Size 424
/W [1 3 1]
/Root 421 0 R
/Info 422 0 R
/ID [<14895AE8C3218939710EBBFF5EAD0E28> <14895AE8C3218939710EBBFF5EAD0E28>]
/Length 1073
/Filter /FlateDecode

stream
...
endstream
endobj

`---

If you find this object with the /Type /XRef you can go to the 
beginning of it, in this case the 80 0 obj and write down the position 
of this object. Then you can go to the end of the file and overwrite 
the startxref 52779 position with you marked position and try to parse 
the document again.

This should work and indicate that the pdf creator you are using, 
creates wrong object positions. Pdfbox can parse only documents that 
provide correct xref tables / streams, otherwise the parser does not 
know how to handle the document.

Best regards
Thomas



Zitat von Rodrigo Caniçali <[email protected]>:

Hi Thomas,

Below is the stacktrace when the option “-nonSeq” is enabled:

Loading PDF D:\Documents and Settings\05215385726\Meus 
documentos\rpf_tributos.pdf
Exception in thread "main" java.io.IOException: Error: Expected a 
long type, actual='!@:g8lJLDX5I'H%oMioAqC?O$d[,X]%dZ#a?Wos'
at org.apache.pdfbox.pdfparser.BaseParser.readLong(BaseParser.java:1668)
at 
org.apache.pdfbox.pdfparser.BaseParser.readObjectNumber(BaseParser.java:1598)
at 
org.apache.pdfbox.pdfparser.NonSequentialPDFParser.parseXrefObjStream(NonSequentialPDFParser.java:460)
at 
org.apache.pdfbox.pdfparser.NonSequentialPDFParser.initialParse(NonSequentialPDFParser.java:358)
at 
org.apache.pdfbox.pdfparser.NonSequentialPDFParser.parse(NonSequentialPDFParser.java:702)
at org.apache.pdfbox.pdmodel.PDDocument.loadNonSeq(PDDocument.java:1139)
at org.apache.pdfbox.ExtractText.startExtraction(ExtractText.java:208)
at org.apache.pdfbox.ExtractText.main(ExtractText.java:85)


When that option is disabled, the following warnings are printed on 
Eclipse console and some text of PDF document is not extracted:

Loading PDF D:\Documents and Settings\05215385726\Meus 
documentos\rpf_tributos.pdf
Nov 04, 2013 10:16:13 AM 
org.apache.pdfbox.pdfparser.XrefTrailerResolver setStartxref
WARNING: Did not found XRef object at specified startxref position 52779
Time for loading: 0.125 seconds
Starting text extraction
Writing to D:\Documents and Settings\05215385726\Meus 
documentos\rpf_tributos.txt
Nov 04, 2013 10:16:14 AM org.apache.pdfbox.util.PDFStreamEngine 
processOperator
INFO: unsupported/disabled operation: o
Nov 04, 2013 10:16:14 AM org.apache.pdfbox.util.PDFStreamEngine 
processOperator
INFO: unsupported/disabled operation: Os
Nov 04, 2013 10:16:14 AM org.apache.pdfbox.util.PDFStreamEngine 
processOperator
INFO: unsupported/disabled operation: a
Nov 04, 2013 10:16:14 AM org.apache.pdfbox.util.PDFStreamEngine 
processOperator
INFO: unsupported/disabled operation: su

Thanks,

Rodrigo



Em Sábado, 2 de Novembro de 2013 10:24, Rodrigo Caniçali 
<[email protected]> escreveu:

Hi Thomas,

Thanks for your answer.

I am afraid the document is confidential, but I canprovide the 
stacktrace and find out if it is possible to generate a 
non-confidential example on Monday when I will be at the office again.

Best regards,
Rodrigo





Em Sábado, 2 de Novembro de 2013 5:50, Thomas Chojecki 
<[email protected]> escreveu:


Zitat von Rodrigo Caniçali <[email protected]>:

Hi,
Hi Rodrigo,

I found on a mailing list of 2012-jun-14 that this problem has been 
already discussed, but here is pretty different.
I think I found the discussion.

I also get the warning "Did not found XRef object at specified 
startxref position xxx" when executing the main function 
of org.apache.pdfbox.ExtractText class. However, some PDF texts are 
ignored and are not printed on the output TXT file. These same texts 
are displayed by Acrobat Reader and can be copyed by the user as 
texts from this program.

Your document is broken and it work with Acrobat Reader, because he 
isn't strict enough against the specification.

Many developer that try to create a pdf writer, test it against the 
Acrobat Reader and does not follow always the specification. So the 
reference is to create Acrobat Reader and not specification conformant 
documents. This lead to the problem that 3rd party libraries like 
pdfbox can't sometimes parse such documents.

In your case the xref table isn't there, where the parser supposing 
it. If you can provide use such document, we can try to find the cause 
of the problem and maybe fixing it.


If the option "-nonSeq" is selected, then appears a 
"java.io.IOException: Error: Expected a long type, actual=..." which 
stops the text extraction.
Maybe you can post the first three lines from the stacktrace, this 
will help debugging the problem.

Please, is there any way to make it work?
It is nearly impossible reconstructing such cases. If you can provide 
us more informations or maybe the document, it will help use improving 
the parser, if possible.

We do our best to support as many document as we can, but in some 
cases we need to be strict to support the existing fine parsing 
documents. This problem is also one point on the agenda of the pdfbox 
2.0.0 version.



Thanks,

Rodrigo

Best regards
Thomas



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