pdfbox-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Balaji Venkatamohan <bvenk...@tibco.com>
Subject Re: How to flatedecode and find all acroform fields in a compressed PDF
Date Wed, 20 May 2015 01:24:02 GMT
Thank you for your pointers and sorry about the image. I am attaching it
with this email.

The point I am trying to make is that the PDF, which was decompressed using
WriteDecodedDoc, is smaller in size than the original PDF given to us by
our customers.
Also, the decompressed PDF generated by WriterDecodedDoc of PDFBox did not
have any PDAcroform fields whereas the decompressed PDF given to us by the
customers does contain Acroform fields. Hence I wanted to know how to
properly decompress the PDF using pdfbox APIs. The reason why I was
analyzing COSStream was to check if the decompression of the compressed PDF
was happening correctly while using PDFBox APIs.
I know it would have been difficult for you to help me without the actual
PDFs. For that, I would like to thank you for your time and pointers.

On Tue, May 19, 2015 at 2:57 PM, Tilman Hausherr <THausherr@t-online.de>
wrote:

> Hi,
>
> The image doesn't appear in the mailing list.
>
> This is all very confusing... /acroform is in the document catalog. I
> don't see how the page content stream is related to it. The best is that
> you either go through the source code, or read the spec and then look at
> the pdf.
>
> To find out what's going on, you'd have to start from that /acroform entry
> and then compare the two files.
>
> It is really difficult to help you without the files. The cause could be a
> bug in pdfbox, or a malformed pdf...
>
> Some more ideas:
> - use loadNonSeq(file, null) instead of load(file)
> - try the unreleased 2.0 version, that one has some improvements in the
> acroform stuff. Note that the API is different.
> https://pdfbox.apache.org/download.cgi#scm
> https://pdfbox.apache.org/2.0/getting-started.html
>
> If you still need help, one possibility would be 1) post the smallest
> possible code that fails, and 2) post a small part of the raw PDF, i.e. the
> objects relevant to the field in your code.
>
>
> Tilman
>
>
> Am 19.05.2015 um 23:03 schrieb Balaji Venkatamohan:
>
>> Moreover, for every page of the compressed PDF (there are 3 pages), I
>> tried getting the COSStream for each of the page :
>>
>> PDPage firstPage=(PDPage)
>> document.getDocumentCatalog().getAllPages().get(0);
>>             pdStream=firstPage.getContents();
>>             COSStream stream=pdStream.getStream();
>>
>> In the above code snippet, the object stream, when analyzed in debug
>> mode, has the following:
>>
>>
>> The line from the compressed PDF as opened with Notepad++ is :
>>
>> <</Filter/FlateDecode/Length 5675>>stream
>>
>> From this point on, using the COSStream object for every page, how can I
>> decompress and find out the acroform fields given that the unFilteredStream
>> object is null for COSStream?
>> ‚Äč
>>
>> On Tue, May 19, 2015 at 1:38 PM, Balaji Venkatamohan <bvenkata@tibco.com
>> <mailto:bvenkata@tibco.com>> wrote:
>>
>>     Thank you for your response Tilman.
>>
>>     I had previously tried using the WriteDecodedDoc for my compressed
>>     PDF and I tried to get the number of acro form fields present in
>>  the output file generated by WriteDecodedDoc. The API still could
>>     not find the acro form fields in the generated decompressed file.
>>      Also the decompressed file generated is 75 KB which is far less
>>     than the original decompressed file which I have (1.6 MB) though I
>>     could edit the acro form fields using acrobat reader.
>>
>>     Thanks,
>>     Balaji
>>
>>
>>
>>     On Tue, May 19, 2015 at 1:18 PM, Tilman Hausherr
>>     <THausherr@t-online.de <mailto:THausherr@t-online.de>> wrote:
>>
>>         Am 19.05.2015 um 21:35 schrieb Balaji Venkatamohan:
>>
>>             My question is: how do I flatedecode a PDF so that I can
>>             find all the
>>             acroform fields within it. ANy help or pointers would be
>>             highly appreciated.
>>
>>
>>         You could try the WriteDecodedDoc option of the command line app
>>         https://pdfbox.apache.org/1.8/commandline.html#writeDecodeDoc
>>
>>         Maybe you can have further ideas by comparing the two files
>>         with NOTEPAD++.... however the two files might have their
>>         objects in different order.
>>
>>         Tilman
>>
>>
>>
>>
>> ---------------------------------------------------------------------
>>         To unsubscribe, e-mail: users-unsubscribe@pdfbox.apache.org
>>         <mailto:users-unsubscribe@pdfbox.apache.org>
>>         For additional commands, e-mail: users-help@pdfbox.apache.org
>>         <mailto:users-help@pdfbox.apache.org>
>>
>>
>>
>>
>

Mime
View raw message