This is an encoder for JBIG2.

JBIG2 encodes bi-level (1 bpp) images using a number of clever tricks to get better compression than G4. This encoder can:

• Generate JBIG2 files, or fragments for embedding in PDFs
• Generic region encoding
• Perform symbol extraction, classification and text region coding
• Perform refinement coding and,
• Compress multipage documents

It uses the (Apache-ish licensed) Leptonica library: http://leptonica.com/

You'll need version 1.68.

Known bugs

The refinement coding causes Acrobat to crash. It's not known if this is a bug in Acrobat, though it may well be.

Usage

See the jbig2enc.h header for the high level API, or the jbig2 program for an example of usage:

$ jbig2 -s -p -v *.jpg && python3 jbig2topdf.py output >out.pdf

or with standalone mode:

$ jbig2 -p -v images/feyn.tif > feyn.jbig2 && python3 jbig2topdf.py -s feyn.jbig2 > feyn.pdf

to encode jbig2 files for pdf creation. If you want to encode an image and then view output first to include in pdf

$ jbig2 -s -S -p -v -O out.png *.jpg

If you want to encode an image as jbig2 (can be view in STDU Viewer on Windows) run:

$ jbig2 -s images/feyn.tif >feyn.jb2

Building

Prerequisites

• installed leptonica including development parts
• installed cmake or [autotools] (https://www.gnu.org/software/automake/manual/html_node/Autotools-Introduction.html)
• installed C++ compiller (gcc, clang, MSVC)
• installed git

Cmake

Windows

Note: cat, rm and dos2unix tool are part of git for windows. You can add them to your path with set PATH=%PATH%;C:\Program Files\Git\usr\bin. Adjust path f:\win64 to your leptonica installation.

"c:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat" x64
set INSTALL_DIR=f:\win64
set INCLUDE_DIR=f:\win64\include
set LIB_DIR=f:\win64\lib
set PATH=%PATH%;%INSTALL_DIR%\bin

Configuration

git clone --depth 1 https://github.com/agl/jbig2enc
cmake -Bbuild -DCMAKE_INSTALL_PREFIX=%INSTALL_DIR% -DCMAKE_PREFIX_PATH=%INSTALL_DIR%
cmake --build build --config Release

Install

cmake --build build --config Release --target install

Uninstall

cat build/install_manifest.txt | dos2unix | xargs rm

Clean

rm -r build/*