Unverified50% confidenceFactExact time
The OCR text layer works by overlaying real selectable text objects at character positions on the rasterized page image, and setting the rendering mode to invisible (Tr 3) or transparent/same as the background color, so that copy-paste, Ctrl+F search, and screen readers work normally.
1
Sources
50%
Confidence
Long-term
Relevance
10/13/2026
First Seen
Sources
Related Entities
Related Claims
UnverifiedThe PDF was generated by a scanner-style pipeline: pages were first rasterized into images, then an invisible OCR text layer was overlaid for accessibility, and the extractor read the vector outline layer (titles, bookmarks), so it returned only the title.73% similarUnverifiedText format exports preserve editable characters, while image format exports preserve the visual appearance.71% similarUnverifiedClient-side redaction tech stacks typically use libraries such as pdf.js to render PDF pages in the browser, Tesseract.js to OCR scanned pages and extract the text layer, and then pixel-level masking or text-layer deletion to complete the redaction.68% similarUnverified使用 Canvas、GPU 直接渲染或自绘 UI 的应用，其屏幕内容无法通过 Accessibility API 或 DOM 解析获取，只能退回到截图加 OCR 路径，这是纯文本屏幕记忆方案最根本的覆盖盲区67% similar
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