Get PDF box data from large PDFs

Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic

   Hi, 

I use the iSED.dll to read the PDF page boxes from the first page of the PDF (MediaBox, CropBox, BleedBox, TrimBox and ArtBox).

First of all, I load the file with LoadFromFile()
Then I read the box information with GetPageBox()

Everything works fine with PDFs < 500MB
With larger PDFs I get an out of memory exeption from the LoadFromFile function (altough running on a PC with 4GB RAM).

I tried to load the file with the DA-functions - this works without exeption, but I can not access the GetPageBox() function with DA.

I get the same results with the newest QuickPDFDLL0717.dll
Cutting the originalPDF in smaller Multipage PDFs is no option.

Anyone who can help me to read page boxes from large PDFs?

Thanks, Peter

Author	Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic
Peter Members Profile Find Members Posts Beginner Joined: 30 Nov 09 Status: Offline Points: 4	Post Options Post Reply Quote Peter Report Post Thanks(0) Quote Reply Topic: Get PDF box data from large PDFs Posted: 30 Nov 09 at 6:55AM
	Hi, I use the iSED.dll to read the PDF page boxes from the first page of the PDF (MediaBox, CropBox, BleedBox, TrimBox and ArtBox). First of all, I load the file with LoadFromFile() Then I read the box information with GetPageBox() Everything works fine with PDFs < 500MB With larger PDFs I get an out of memory exeption from the LoadFromFile function (altough running on a PC with 4GB RAM). I tried to load the file with the DA-functions - this works without exeption, but I can not access the GetPageBox() function with DA. I get the same results with the newest QuickPDFDLL0717.dll Cutting the originalPDF in smaller Multipage PDFs is no option. Anyone who can help me to read page boxes from large PDFs? Thanks, Peter

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3530	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 01 Dec 09 at 6:27AM
	Hi Peter! I didn't make the described experiences with the newer versions of QuickPDF but two years ago i've posted a code how to handle these memory-problems. In short: do a Free from time to time and keep the current page in mind and go on with a new instance... Cheers, Ingo - - - Memory and time is often a problem working on big pdf files with quickpdf. It seems to me that in many code parts memory won't resetted ... I'm using something like this: QP := TiSEDQuickPDF.Create; try QP.UnlockKey('mycode'); dafh := QP.DAOpenFile(edit,''); x := QP.DAGetPageCount(dafh); STR := ''; verztxt := edit + '.txt'; AssignFile(cf,verztxt); Rewrite(cf); pc := 0; for i := 1 to x Do begin dapr := QP.DAFindPage(dafh,i); QP.CombineLayers; STR := QP.DAExtractPageText(dafh,dapr,3); WriteLn(cf,Trim(STR)); pc := pc + 1; if ( pc = 10 ) Then begin pc := 0; QP.DACloseFile(dafh); QP.Free; QP := TiSEDQuickPDF.Create; QP.UnlockKey('mycode'); dafh := QP.DAOpenFile(edit,''); end; // . . . This works fine on big files for textextraction - no problems anymore for me. After few pages i'm using "free" and then a new "creation" ... This needs only less time and avoid memory-exceptions for me.

Peter Members Profile Find Members Posts Beginner Joined: 30 Nov 09 Status: Offline Points: 4	Post Options Post Reply Quote Peter Report Post Thanks(0) Quote Reply Posted: 01 Dec 09 at 9:57AM
	Hi Ingo Thanks for your reply! The main problem still remains: I have no access the the GetPageBox() functions when I open a file with DAOpenFile(). Any idea how to get the PDF-Box information (trimbox, mediabox, cropbox, ...) with DA?

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3530	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 01 Dec 09 at 12:01PM
	Hi Peter! So why not use the functionality your ide is offering? You can do this job without any pdf-sdk. Open the pdf with an editor and you'll know what i mean. You'll find things like this: 451 0 obj <</CropBox[0.0 0.0 595.276 841.89]/Parent 587 0 R/StructParents 27/Contents 453 0 R/Rotate 0/BleedBox[0 0 595.276 841.89]/MediaBox[0.0 0.0 595.276 841.89]/TrimBox[0 0 595.276 841.89]/Resources 452 0 R/Type/Page>> endobj Cheers, Ingo

Peter Members Profile Find Members Posts Beginner Joined: 30 Nov 09 Status: Offline Points: 4	Post Options Post Reply Quote Peter Report Post Thanks(0) Quote Reply Posted: 01 Dec 09 at 12:34PM
	Hi Ingo I have my application written in Delphi 7. Intention of the program is to collect and enter job information by the user. Part of those information are the PDF box information. To help fill in the jobmask automatically, the PDF box information are read from a PDF after the user selected a PDF from the file system. Thats why I use the iSED.dll The Box information could be read and entered 'manually' by the user, but he needs then e.g. AdobeAcrobat Prof to see the PDF box information. The PDF box info has to be read automatically from my application, without opening another Editor.

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3530	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 01 Dec 09 at 2:37PM
	You don't want to understand me ;-) The editor was only an example to show you that you can see this all without any decryption routines. Read the filecontent directly into a string or stream and search for "your boxes" ;-) It's easy! Cheers, Ingo

Peter Members Profile Find Members Posts Beginner Joined: 30 Nov 09 Status: Offline Points: 4	Post Options Post Reply Quote Peter Report Post Thanks(0) Quote Reply Posted: 01 Dec 09 at 3:15PM
	Ok, now I know what you mean, I'll try that. Thanks a lot for your help! Regards, Peter