January 14, 2025 Updated: January 26, 2025

PDF Ink is a new plugin for WordPress (and standalone PHP library) for PDF file manipulation... and it just dropped January 2025! Come celebrate with us!

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April 23, 2025

In our digital age, sharing valuable or sensitive information securely is paramount, but unfortunately it’s also tricky. Portable Document Format (PDF) files are widely used for their versatility and ease of sharing/viewing. PDF is an open file specification, meaning not only can anyone build a PDF, but anyone can build a PDF builder/reader application. There are good and not-so-good PDF files just like there are good and not-so-good PDF applications. If you open a PDF file with a text editor application, you can see what a PDF is made of: a bunch of numbers, letters, and strange characters. One can view the PDF “guts” and edit them, assuming they understand […]

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March 12, 2025 Updated: April 3, 2025

PDF Ink is a favorite among composers and sheet music sellers because it allows licensing information to be added anywhere on the page, right up to and even over the page margins. One of our customers, Guillaume, is using the Checkout Field Editor for WooCommerce plugin to enhance a checkout form with a field requiring buyers to enter their ensemble name, like “University Concert Choir.” Guillaume would like to have a Magic Tag called [ENSEMBLE] to use for printing the ensemble name on purchased PDF files. Let’s walk through how to set this up so the ensemble name then appears stamped on the PDF, clearly marking it for that specific […]

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February 13, 2025 Updated: March 17, 2025

It’s rare for users to reach out with concerns about stampers placing watermarks over PDF text, but recently there was another inquiry about this—bringing the total to three—and the frustration expressed was evident. Maybe since all the other plugins default to placing stamps over existing text and images, people assume that’s what is possible. Or maybe people are being told it’s impossible to stamp PDFs below existing text and images. That’s not true. (If you want the TL;DR, skip to the small text at the very end of this article.) To assist those desiring to literally “flip the script,” here are some helpful tips on managing PDF watermark layering, positioning, […]

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January 23, 2025 Updated: March 17, 2025

Look ma! No WordPress required! In the documentation for PDF Ink, it is explained how to write a simple script to fire up the PDF Ink PHP library and stamp a PDF file. The library is written in such a way that it can be used without WordPress, and any one of six different PDF-manipulation library sets can be used. This is helpful when one set doesn’t work with a specific PDF, but another set might. As always, when PDF Ink fails for any specific PDF, the solution is to either attempt to repair the PDF — or upgrade to a better library, like SetaPDF-Stamper. The example in the documentation […]

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December 22, 2024 Updated: March 20, 2025

Adobe SDK The JavaScript-based Adobe PDF Embed API allows us to embed PDF viewers, showing manipulated (encrypted/passworded and/or stamped) PDFs on our WordPress site using PDF Ink shortcodes. These embeds can be highly customized using filter hooks, becoming handsome and useful interfaces for your users. It is up to you and/or your developer to familiarize yourself with use of the API and the Adobe SDK PDF appearance/function control options in order to customize your embeds further. Using a default PDF Ink embed shortcode with its defaults might be just fine for your purpose. But it isn’t too hard to customize using PHP. SDK parameters are filtered by PDF Ink in […]

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August 4, 2024 Updated: March 17, 2025

This week I got finally got involved with maintaining the languishing TCPDF library on Github. Long overdue. Embarrassingly long overdue, since I’ve based one of my businesses on this open source gem for nearly ten years now. The author, Nicola Asuni, has been working for many years on a successor to TCPDF, but it is stalled… likely due to the usual reasons: life and cash. I can relate. I’ve been sitting on a huge WP plugin project for two years now, desperately trying to move it forward while life happens and I’m forced to prioritize support for my paying customers. A couple years ago an eager young programmer, William Desportes, […]

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November 13, 2023 Updated: March 20, 2025

Here is some PHP code for WordPress/WooCommerce which will make PDF Ink recognize TWO custom shortcodes in any watermark content: [VARIATION_DESC] and [VARIATION_NAME]. These translate to variation description and variation name, both aspects of a WooCommerce variable product. This code (everything above the dashed line) should get added anywhere in your functions.php file. If unsure where to put it, add it at the end of the file. You could also add the snippet using the WordPress plugin called “CODE SNIPPETS” (front and back end). This snippet development was sponsored by customer Michael. Thanks Michael! For reference (maybe for people migrating from WaterWoo to PDF Ink) here is a snippet which […]

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October 27, 2023 Updated: March 17, 2025

The two best plugins available for WooCommerce PDF file download watermarking/passwording are WooCommerce PDF Watermark and PDF Ink (sold here). If you’re considering purchasing one or the other, this post will clearly show you which is the better choice — by far. Both plugins have been available for many years, both plugins perform the same essential tasks, and yet they are quite different under the hood. They offer different features, and at different price points. What’s under the hood: Both plugins use free, open-source PDF manipulation libraries to accomplish passwording and watermarking. WooCommerce’s offering uses FPDI to parse PDFs and FPDF to re-write them.As of October 2023, WooCommerce is using […]

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April 26, 2023 Updated: January 22, 2025

PDFs are a fantastic way to share documents – they preserve formatting, are widely compatible, and can even be compressed for easy transmission. But what if that PDF contains sensitive or monetized information? The Portable Document Format (PDF) offers some security, which when stacked can be quite effective. These include: Watermarks: A Visual Deterrent A watermark (also called a stamp) is usually a semi-transparent image or text stamped onto the background of each page in a document. The watermark can be your company logo, a confidentiality notice, or even a name or # copies authorized, or a copyright notice. While watermarks can’t completely prevent copying, they do make unauthorized distribution […]

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April 17, 2023 Updated: March 20, 2025

A customer wrote with a neato request last month. If one WooCommerce product had several PDFs, and wasn’t a variable product, how could each PDF in the list be watermarked differently from the others? There is no setting for that inside PDF Ink because WooCommerce hasn’t exactly made that function easily possible, and also because it somehow hadn’t been requested until last month. That’s sort of amazing considering how long the plugin has been around! Anyway, it was a good request and so we added a filter hook called ‘pdfink_woo_filter_settings‘. (This hook replaces the ‘wwpdf_filter_settings_array’ in WaterWoo PDF Premium, with identical arguments.) Filtering Settings Because WooCommerce — unlike Easy Digital […]

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February 25, 2023 Updated: March 17, 2025

There are several ways to go about getting the attachment ID (of the ‘attachment’ WordPress post type, stored in the wp_posts WPDB (WordPress Database) table. Here are some of them: From the Media Library: Navigate to Dashboard -> Media. Here you will see your WordPress uploads (Media), either in grid view or list view. They’re both fine, it’s just a preference thing. Instructions for both are below. You can click the small icons to change the Media view from list to grid or vice versa. List View If in List view, navigate to the item by scrolling or using the search bar at the top right. Then hover over the […]

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