I opened the interview_compressed in notepad++ and did not see any 'Acroform' text anywhere. However, as Maruan suggested, I entered some data into what looks like form fields of interview_compressed.pdf and saved it. When I opened this file in notepad++, I did see 'Acroform' text in it. I also noticed an increase in file size from 21 KB to ~530 KB.
I then ran this filled saved compressed PDF in pdfdebugger.java and saw that the field values were getting stored but not under Acroform fields but under Annotations. Please refer to this image: http://imageshack.com/a/img540/9951/QGLDtS.jpg So, whatever the compression technique was, it simply made all the Acroform fields disappear from the original PDF but retained all annotations which also contain the interactive forms and this helped reduce the file size so much? If this is the case, can pdfbox API also use similar compression technique to compress such a a huge file into a smaller one? On Fri, May 22, 2015 at 1:25 PM, Maruan Sahyoun <[email protected]> wrote: > Hi, > > > Am 22.05.2015 um 21:54 schrieb Tilman Hausherr <[email protected]>: > > > > Am 22.05.2015 um 17:53 schrieb Balaji Venkatamohan: > >> Hello, > >> > >> I used PdfDebugger to make the internal PDF structure of the two files > (1) > >> interview.pdf and (2) interview_compressed.pdf visually available and I > >> have uploaded my images to imageshack. Here are the four links: > >> > >> http://imageshack.com/a/img538/8277/JghCpG.jpg > >> http://imageshack.com/a/img909/6140/KsYNGR.jpg > >> http://imageshack.com/a/img903/8644/mk15As.jpg > >> http://imageshack.com/a/img901/8610/NXe3mJ.jpg > >> http://imageshack.com/a/img673/8633/0GMdjQ.jpg > >> > >> The first two links are from the internal structure of interview.pdf > >> (original uncompressed file) > >> The third and fourth links are from the internal structure of > >> interview_compressed.pdf (compressed file) > >> The fifth link compares the file sizes of the two files and as you can > also > >> see, the difference is huge. > >> > >> As you might notice, the file interview_compressed.pdf has no acroform > > > > Indeed... but this is needed - from the spec: > > > > "The contents and properties of a document’s interactive form shall be > defined by an interactive form dictionary that shall be referenced from the > AcroForm entry in the document catalogue (see 7.7.2, “Document Catalog”). > Table 218 shows the contents of this dictionary." > > > > correct > > >> fields listed even though opening the PDF in pdf reader allows me to > enter > >> values in places which look like AcroForm fields and also save them. Are > >> there any other PDF 'types' similar to Acroform fields which would > enable > >> users to fill data and which can be accessed in PdfBox APIs without > having > >> to go through PDAcrofield? > > > > Yes, annotations... there are some common parts, but this is just a > vague observation from me, I'm not the acroform specialist. > > from a first glance it looks like there are all entries necessary to (re-) > generate the form fields. That's what's likely happening for this document > in Adobe Reader. Would be interesting to see what's being save after the > forms has been filled out and saved using Acrobat. We'd need a test form to > come up with an enhancement like this. > > BR > Maruan > > > > > > What you should do: use NOTEPAD++ to look whether there's "/AcroForm" in > the "compressed" file. > > - if it is missing, tell the client (or your boss) just that > > - if it isn't missing, then there's some problem in PDFBox (try also the > loadNonSeq I mentioned earlier) > > > > Tilman > > > >> > >> You can use qpdf , then use these options: > >> > >> I will now try using this link to compress the original file. > >> > >> Another strategy to think about - can your client generate a > >> non-confidential file, so that you can share it, and the "compressed" > file? > >> > >> I wish I had direct communication with the clients but due to > bureaucracy, > >> I am having to go through multiple layers to get my message across to > them. > >> I will share more information as soon as I have them. > >> > >> PS: i sent these image links to my personal email first to make sure > that I > >> can open them. I could and so I am hoping you all could too. If you are > >> unable to open them, please let me know. > >> > >> Thanks, > >> Balaji > >> > >> > >> On Fri, May 22, 2015 at 6:45 AM, Tilman Hausherr <[email protected] > > > >> wrote: > >> > >>> Am 22.05.2015 um 08:28 schrieb Andreas Lehmkühler: > >>> > >>>> Hi, > >>>> > >>>> Balaji Venkatamohan <[email protected]> hat am 20. Mai 2015 um > 03:24 > >>>>> geschrieben: > >>>>> > >>>>> > >>>>> 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. > >>>>> > >>>> Maybe it's worth to try to share the file "visually" with us. Open > both > >>>> files > >>>> (compressed and decompressed) with PDFDebugger [1] and post a > screenshot > >>>> of both > >>>> somehwere (dropbox etc.) and share the link with us. Maybe that could > >>>> shed some > >>>> light on your issue. > >>>> > >>> @Balaji: here's an example on how such a screenshot would look like: > >>> http://home.snafu.de/tilman/tmp/pdfdebugger-screenshot.png > >>> > >>> Tilman > >>> > >>> > >>> > >>>> BR > >>>> Andreas Lehmkühler > >>>> > >>>> [1] http://pdfbox.apache.org/1.8/commandline.html#pdfDebugger > >>>> > >>>> On Tue, May 19, 2015 at 2:57 PM, Tilman Hausherr < > [email protected]> > >>>>> 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? > >>>>>>> > >>>>>>> > >>>>>>> On Tue, May 19, 2015 at 1:38 PM, Balaji Venkatamohan < > >>>>>>> [email protected] > >>>>>>> <mailto:[email protected]>> 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 > >>>>>>> <[email protected] <mailto:[email protected]>> 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: > [email protected] > >>>>>>> <mailto:[email protected]> > >>>>>>> For additional commands, e-mail: > [email protected] > >>>>>>> <mailto:[email protected]> > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> > --------------------------------------------------------------------- > >>>>> To unsubscribe, e-mail: [email protected] > >>>>> For additional commands, e-mail: [email protected] > >>>>> > >>>> --------------------------------------------------------------------- > >>>> To unsubscribe, e-mail: [email protected] > >>>> For additional commands, e-mail: [email protected] > >>>> > >>>> > >>> --------------------------------------------------------------------- > >>> To unsubscribe, e-mail: [email protected] > >>> For additional commands, e-mail: [email protected] > >>> > >>> > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [email protected] <mailto: > [email protected]> > > For additional commands, e-mail: [email protected] <mailto: > [email protected]> >
