PDF text is visible but cannot be extracted: how do you distinguish scans and broken text layers?

Check whether page text can be selected and copied

This applies to empty scans, copied gibberish and mixed-quality pages within one document. Preserve originals and representative page types and record selection and copying behavior. Some PDFs draw letters as outlines or use complex encodings; visible writing is not always a normal text layer.

Separate image pages, font mappings and hidden text

Inspect main images, extractable text and hidden OCR layers and compare characters with visible originals. Font mapping, reading order and duplicate text can fail; tables additionally need row relationships. Faithfully extracting a wrong hidden layer still produces wrong content, so character count is not quality.

Choose extraction or OCR by actual page type

Prefer direct extraction for genuine text and appropriate-language OCR for scans or unreliable layers, preserving page references. Avoid repeating OCR indiscriminately and introducing errors or duplicates. Verify representative pages before full processing and inspect numbers, names and important table structure before using extracted text in answers.

Compare visible content and extracted text page by page

Check coverage per page, reading order and high-risk values and verify normal text pages did not regress. Preserve uncertain regions and page numbers for review. Acceptance requires source-faithful extraction and explicit coverage, not longer output or a file opening. Keep blurred words uncertain.

This article read no private PDF or ran a new OCR task. Test methods on copies. Extractor encoding and layout support varies and OCR cannot guarantee blurred-text recovery. Respect encryption and access permissions instead of disabling protection. Identify unrecovered pages or damage explicitly.