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libjel -- JPEG Embedding Library

This library supplies an API for embedding and extracting bit strings into / from JPEG images. The library uses heavily quantized frequency components to provide storage that is stabilized by the JPEG compression process. As a result, embedded bit strings are preserved under a number of different transformations, including transcoding to higher quality, DC or low frequency shifts in pixel value, and limited image rescaling.

Please see "TRIST: Circumventing Censorship with Transcoding-Resistant Image Steganography" for a detailed explanation on what this tool does and how it does it. A copy can be found here:

https://github.com/SRI-CSL/jel/blob/master/doc/jpegsteg.pdf?raw=true

General Compilation

Prepare the raw git repository first and generate configure and Makefile:

autoreconf -fvi
./configure --enable-silent-rules

To compile manually:

make

Debian

To make a Debian package:

dpkg-buildpackage -b -us -uc