Format
DjVu File Format
Summary
- Name
- DjVu File Format
- Identifiers
-
- PUID: fmt/255
- MIME: image/x-djvu
- Format type
- Image (Raster)
- Description
- The DjVu file format is an image file format used primarily for storing scanned documents. The format, developed by AT&T Labs, is based on the Interchange File format. There are three elements that comprise a DjVu encoded image file: the mask which is encoded using the JB2 algorithm; the background encoded using the wavelet-based compression IW44; and the foreground, containing the colour of the text and the line drawings, also encoding using IW44. The background and foreground are usually lower resolution (100 dpi) colour images with the mask at a higher level resolution (e.g. 300 dpi).
- Format encoding
- Text
- File extensions
-
djvu,djv - Submitted by
- National Library of Singapore / National Library Board Singapore
- Developed by
- Caminova Corporation
- Supported by
- Caminova Corporation
Internal signatures
DjVu File Format
- Description
- Header ASCII: AT&T followed by container Chunk FORM, then either DJVMDIRM or DJVUINFO as secondary identifiers to DjVu document type. This is a generic signature which will identify all DjVu files up to DjVu specifications v3. No distinction is made between single or multi page documents, or any internal image encoding.
- Provenance
- Ongoing DROID research work, following request from National Library Board Singapore.
Byte sequences
- Min Frag Length
- Absolute from BOF
- Offset
- 0
- Max offset
- None
- Byte Sequence
41542654464F524D{4}(444A564D4449524D|444A5655494E464F)- Endianness
- None
Changelog
-
V125
- Release date
- 7 September 2026
-
Updated
DjVu File Format: Description correctly updated. Submitted by Digital Research Alliance of Canada - Federated Research Data Repository / Alliance de recherche numérique du Canada - Dépôt fédéré de données de recherche.
-
V120
- Release date
- 25 February 2025
-
Updated
DjVu File Format: New description added as part of PRONOM Research Week 2024. Submitted by Digital Research Alliance of Canada - Federated Research Data Repository / Alliance de recherche numérique du Canada - Dépôt fédéré de données de recherche.
-
V46
- Release date
- 8 February 2011
-
Added signature
DjVu Format: Signature developed through PRONOM Research.
-
Updated
DjVu Format: Record title updated from Document Express with DjVu Professional Edition and version information removed.