All tests run on an 8-year-old MacBook Air.

Drawing a black rectangle over text is not redaction.

The text is still there. Select all, copy, paste into Notepad — it appears. This has leaked classified documents from actual government agencies. Multiple times.

Real redaction destroys the underlying data. Here's how I implemented it.

What fake redaction looks like

PDF structure (fake redaction): Page content stream: "Salary: $120,000" ← still here Annotation layer: [black rectangle] ← just covering it

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The content stream is untouched. Any PDF parser can read it.

What real redaction requires

Find the target text in the content stream

Remove it from the stream entirely

Replace with a filled black rectangle drawn directly into the content

Re-serialize the page — no original data survives

pub fn redact_text ( doc : & mut Document , page_id : ObjectId , target : & str , ) -> Result < (), lopdf :: Error > { let page = doc .get_object_mut ( page_id ) ?…