PDFi: Low-level PDF inspector and editor

PDFi is a simple tool for displaying the low-level structure of a PDF file in an interactive tree view. Arbitrary values can be modified or deleted. The motivation for PDFi is to allow modifying a PDF file in a precise, minimally invasive way; for example, to remove a portion of text or a watermark, without affecting the rest of the PDF file. Most naïve approaches to doing this involve converting the PDF file into a more editable file format, which introduces complexity and dependencies. For example, using Inkscape requires converting the PDF to SVG internally. Text rendering then becomes dependent on having the original font available for use by the system's text renderer. Alternatively, the original text can be rendered to paths, which greatly increases the file size and removes machine readability. Both approaches have large, undesirable side effects on the PDF file structure. More bespoke tools for editing PDF files (e.g. the recent and very promising word-sys-pdf-editor) can…