What is a .JBIG2 file?
JBIG2 is the successor to JBIG for scanned documents, reusing repeated symbols (like the same letter) to compress text images very tightly.
- Did you know
- JBIG2’s symbol matching once caused a scandal when some photocopiers silently swapped digits in scans by reusing a near-identical glyph.
- A 2013 Xerox scanning bug was traced to JBIG2's symbol-matching: at low quality it could substitute a stored glyph that merely looked like the original digit.
- JBIG2 splits a scanned page into a reusable dictionary of symbols plus their positions, which is what lets it compress text images so tightly.
- What Analyser reads
- Decode and preview extra still-image formats in pure JavaScript - Truevision TGA, QOI, Netpbm (PPM/PGM/PBM), PCX, farbfeld, WBMP, XBM/XPM, Sun Raster and SGI are fully rendered - and read header metadata from codec-heavy formats: Radiance HDR, DirectDraw Surface (DDS) game textures, OpenEXR, JPEG 2000, JPEG XR, EPS/PostScript, Windows WMF/EMF metafiles, Apple ICNS icons, CUR/ANI cursors, MNG and Lottie animations.
- Depth of analysis
- .JBIG2 is an identification-grade format: Analyser recognises it from its bytes and decodes the header metadata it carries, rather than opening it in a full viewer. Formats that do get a full viewer are marked "Full" on the formats page.
- Open a .JBIG2 file
- Drag a .JBIG2 file onto the Analyser home page (or tap to pick one). It is identified entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.