PDF knowledge
Find articles that provide you with practical insight into the world of PDFs. Learn all the ins and outs of PDFs, from the fundamentals to the best practices.
Tech corner
Is the PDF version information a neglectable detail?
Each PDF file starts with a header comment that carries version numbers. What do they mean? Can a reader ignore these numbers or what is it to do? Is there any other version information that a reader should take care of?
Tech corner
Converting invoice documents to the ZUGFeRD data format
XML or PDF? That's one of the most heard questions when it comes to invoice document formats. XML is the preferred format for machines whereas PDF is the format for humans. But why not have the cake and eat it? With ZUGF ...
Tech corner
A good PDF printer tool can be amazingly versatile
As the name suggests a PDF printer tool is meant to put the contents of a PDF document onto paper. However, it is surprising how many applications can be built when using a printer tool in collaboration with the Windows ...
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How to process device specific colors in PDF
The chapter about rendering in the PDF standard specifies how to transform colors from one device specific color space to another and gives hints on how to transform calibrated colors to device specific colors. But most ...
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A best practice for using output intents
Output intents describe the characteristics of the device on which a document is intended to be rendered. Traditionally, the target device is a printer. But, how about display monitors?
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How to create tagged PDF/A from Microsoft Word documents with decent quality
Microsoft Word offers an add-in to save a document as a PDF/A file. Good to hear, I thought. I ran the output through the PDF Validator for a standards conformance check. No complaints. That's great, isn't it. So, I shed ...
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Utility to simplify the import of certificates and private keys into a PKCS#11 cryptographic token (HSM)
The 3-Heights™ Security API supports the creation and verification of digital signatures using a cryptographic token via a PKCS#11 interface. However, the component can only be used if the token has appropriate certifica ...
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Do the PDF scan conversion rules have an impact on anti-aliasing?
The scan conversion rules in PDF are special in the sense that none of the publically available graphics libraries implements them. On the other side almost every PDF rendering engine implements an anti-aliasing mechanis ...
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PAdES - PDF Advanced Electronic Signature
What is PAdES? What does it have to do with PDF? What can PAdES do? For all these questions, there are detailed answers on the web. This article is meant to give a brief overview as a small guide in the jungle of terms.
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PDF 2.0 - A quick overview
It is rare for industrial products to survive for more than 20 years – especially in the IT industry. Not even the inventors of the PDF could have imagined just how successful their file format would be when they launche ...
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Handling embedded and non-embedded fonts in PDF & PDF/A documents
Although the first part of the PDF/A standard was published in 2005 there is still a need for some clarifications regarding fonts and embedding. What does the standard exactly require? How should PDF to PDF/A converters ...
Tech corner
Scan to PDF/A - some insights
Traditionally a scanner produces a TIFF or JPEG image for each page. Some of them can directly produce PDF files. And newer devices produce files conforming to the PDF/A standard. However, the quality of the produced fil ...