technique reference · by file type
Hidden text in PowerPoint presentations
A presentation can carry text the audience never sees: speaker notes, hidden slides, text parked outside the slide, white or transparent text, words covered by a shape, and prompt text left in a template's master slides.
Extract the text from a deck and all of it comes back, which is how a hidden instruction reaches an AI model summarising the file. Below is every way we detect hidden text in PowerPoint files.
ppt.master-inheritedPlaceholder prompt text carried in a legacy .ppt slide master — the template's own "click to edit" wording — which reaches every extractor and renders on no slide.pptx.alt-textA shape's accessibility description, which reaches a screen reader and an extractor and nobody else.pptx.commentReviewer comments attached to slides — working notes that no presentation displays.pptx.hidden-slideA slide marked "Hide Slide": skipped when the deck is presented, fully present in the file.pptx.master-inheritedText sitting in a slide layout or master placeholder, which no slide ever renders.pptx.occluded-textA text box with an opaque shape or picture drawn on top of it, hiding the words behind an object.pptx.offslideA text box positioned in the scratch area outside the slide canvas, where nothing renders it.pptx.speaker-notesText typed into the notes pane of a slide, which the presenter sees and the audience never does.pptx.tiny-fontA run set small enough that no reader resolves it on a projected or printed slide.pptx.white-textA run whose text fill is too close to whatever is painted behind it to be read.pptx.zero-opacityA run whose text fill is set to complete transparency, so nothing of it is painted.
shared by every Office file
ooxml.embedded-font-remapAn embedded font maps a digit to a glyph that cannot be that digit, so a reader sees different numbers from the ones the document stores.ooxml.raster-instructionAn embedded image was read and the text inside it is shaped like an instruction aimed at a model.ooxml.uninspected-embedded-objectA document embedded inside this one could not be opened, so whatever it contains was not analysed.ooxml.uninspected-fontThe document embeds a font whose glyph mapping this engine could not read, so the extracted text may differ from what a reader sees.ooxml.uninspected-partA part inside the OOXML package carries text that the format's parser never opened, so its contents were not analysed.ooxml.uninspected-rasterThe document carries an embedded image large enough to hold readable text that this engine did not read.