Question 1

What is the difference between the three views?

Accepted Answer

Side by side shows both pages of every pair together — scrolling is automatically in sync. Overlay computes a pixel-level red/green diff of each pair. Text changes lists every word-level difference with a jump button.

Question 2

One file has a page more than the other. How does the pairing work?

Accepted Answer

Smart mapping (default) aligns pages by their text similarity, so a page inserted mid-document shifts the pairing instead of marking every later page as changed. Position mapping simply pairs page 1 with page 1, page 2 with page 2 — the surplus shows as added or removed.

Question 3

Does it work with scanned PDFs?

Accepted Answer

Yes — the overlay view is exactly for scans: it compares the rendered pixels, so it catches changes even without selectable text. The text change list needs selectable text; run the OCR tool first for scanned files.

Question 4

What does the sensitivity control change?

Accepted Answer

It sets how small a difference counts as a change: High flags subtle pixel differences and near-identical pages, Low only flags clear changes. Use High for scans or anti-aliased exports, Low for noisy scans that differ everywhere.

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