SPDF · Semantic Processed Document Format

Until now a document was an opaque surface: a PDF, a video, an audio file. SPDF opens it. An open standard for documents that have already been read: a single SQLite file in which every passage carries its exact anchor (printed page, folio, second, slide, line of verse) so that a citation can only print what the source says. Specification 5.0, twelve implementations, all independent, that pass the same conformance suite, and a free reader for desktop, Android and the web.

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