DjVu vs PDF for scanned documents
Keep the DjVu source when you want to preserve the file you received. Export a PDF when the recipient, reader, or submission system requires PDF. Keeping both avoids replacing the source with a conversion.
Compare the formats
Section titled “Compare the formats”| Requirement | DjVu | |
|---|---|---|
| Reading support | Requires a compatible reader | Supported by many browsers and document apps |
| Scan size | Can be compact with layered compression | Depends on image encoding and resolution |
| Search and copy | Requires a text layer | Requires text, including an OCR layer for scans |
| Annotation | Depends on the reader | Supported by many PDF editors |
| Archive submission | Check the archive’s accepted formats | Some archives require a specific PDF/A profile |
File size and quality
Section titled “File size and quality”Neither format guarantees a particular size or image quality. Compare the same pages at readable resolution. A PDF made from a DjVu may be larger, and reducing resolution can remove detail. Conversion cannot restore detail missing from the source.
The DjVuLibre documentation explains DjVu compression and file structure.
Searchable text
Section titled “Searchable text”Both formats can contain page images without usable text. OCR creates a searchable text layer but can introduce recognition errors. Inspect copied text against the original page.
Export a copy
Section titled “Export a copy”Niraqua DjVu exports DjVu to PDF on Mac, iPhone, and iPad, with optional OCR. Choose all pages or a range. See convert DjVu to PDF.
A PDF export is not a claim of PDF/A compliance. If an archive specifies PDF/A, validate the file against the required profile before submitting it.