publickey encryption key calculation
In PDF specification section 3.5.3 Public-Key security handlers, it is mentioned that once you get the 20 bytes seed from the PKCS#7 enveloped data, the following steps needs to be followed to...
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Different font rendering depending on image transparency
Hi,this is a cross-post from the Adobe Reader forum, where no one was able to help me. It is about PDF rendering issues in Acrobat Reader, concerning pdf files created with latex. I would be glad if...
View ArticleAcrobats PieceInfo for Header and Footer spec?
Hi, I would like to process PDF documents with Headers, Footers and Watermarks added by Acrobat. There is a Private application data (PieceInfo) in added Header, Footer and Watermarsk XObjects called...
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Problem with transparent image
Hi everyone, I'm having problem with embedding transparent image to PDF. Thin border appears when viewing the document with Adobe Reader, Adobe Acrobat Pro and even with Foxit Reader. But there are no...
View ArticleParent/child fonts problem
Hi all I'm developing a program which has been writing out servicable PDF files for a few months, with embedded Truetype fonts; the files open without problem and display correctly. However, I am now...
View ArticleInverse y axis and text
When we draw in windows the origin is at the upper left point.I tranform it to the lower left with matrix M=[sc, 0, 0, -sc, 0, y] where sc is some scaling and y the height of the window.The result...
View ArticleAre CR and LF actually critical in some places?
I have two PDF files that are identical except that one has an odd mix of CR, CR-LF, and LF for line breaks, and the other uses CR-LF exclusively (and has the stream lengths, object offsets, etc....
View Articleinvalid byte range in PKCS#1 signature
Hello, this is my first post in this forum and I am thank you in advance for your help. I am developing a component to sign PDF. I am getting invalid byte range error for the signed PDF document from...
View ArticleHow large can a PDF file be?
This question is not just strictly about the spec, it's also about what the most common readers will accept. So the file offsets are 10-digit numbers, is the maximum safe offset 2,147,483647 or...
View ArticleSecond digital signature invalidates the first one
Hello to all, I'm having some troubles adding a second digital signature to an already digitally signed PDF. The library that I'm using in order to handle the PDFs is an open source one, so I'm...
View Articlepassword encryption with 256 bit AES algorithm...???
I have an application for the decryption of pdf passwords for 128 bit Rc4 and 128 AES. In this, i am doing 50 times MD5 using an encryption key. Its working well with this approach. But in case of 256...
View ArticleRotating text in PDF
Hi there,For some of my work, I'm trying to create a bunch of diagrams and graphics of different kinds directly in PDF. I've written a little Python library to help me do this. The spec is very easy to...
View ArticleCTM and BT
So.. I have two PDFs. I'm trying to find the positions of characters in these PDFs.For the BT operator, I am doing this:TextMatrix = new Matrix();TextLineMatrix = new Matrix();//CTM = new Matrix();Now,...
View ArticleStandard Encryption example data
Hi, i write an application that generates an encrypted PDF, so i encrypt Strings and ContentStreams. Encryption involves many steps after each other and i'm not sure where inbetween my encryption fails...
View ArticleIncremental update with XObject problem.
My app is working pdf, annotating etc...So, most of the docs are ok, but some of them becomes broken.For example, i've added a new XObject (image) to the first page of doc and incrementally updated the...
View Articlesame dictionary for document info dictionary and Page Tree
Hi, recently i came across a pdf file which had the same dictionary for the info dictionary and the page tree.Thus this "dictionary" looked like this: 5 0 obj<</Author (author) /Count 1...
View ArticleXRef Stream
I've noticed that the new cross reference stream isn't as nice to me as the 1.4 version. I've deflated the stream and don't make too much sense of how to get my object file offsets. Here is my...
View ArticleHow best to find syntax errors in a PDF
Hi, I want to find out the best way for an end user to identify syntax errors in a PDF, such as "expected a dict object", which might occur when a user opens the PDF. I usually find these when using...
View ArticlePDF/A vs. Form Fields (checkboxes, radiobuttons)
I've question regarding the PDF/A specification and would appreciate some clarification.The specs says: "If an annotation dictionary contains the AP key, the appearance dictionary that it defines as...
View Articleembed pcl or postscript commands in pdf
Hello! I am currently facing the problem, that I want to specify the paper-source tray for the pages of a pdf, that is sent directly to the printer. I know that there is no way to do this directly in...
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