jpegblur - "lossless" "blurring" of regions in JPEG image
=========================================================

jpegblur is a program to blur regions of a JPEG image while minimising
changes in the image file.

jpegblur takes bounding boxes from command line and returns a JPEG
image with those regions blurred.  It does this in DCT space thus
avoiding the introduction of new compression artefacts outside the
blurred region.  The blurring approach is the same as the one
described in [Yang et al, 2021](https://arxiv.org/abs/2103.06191).

jpegblur also preserves all metadata by copying all extra markers,
similar to jpegtran, a program distributed with libjpeg for lossless
transformation of JPEG files.

The purpose of this program is to redact Personally Identifiable
Information (PII) while avoiding any other changes to the image file.
Do note that there may be PII on the metadata and it will be copied
across untouched.  Some other tool can be used to inspect the
metadata.


Usage
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    jpegblur [x0,x1,y0,y1 ...] < input.jpg > output.jpg

See the source code for a man page style documentation.


Build
-----

You should install this from release sources and follow the standard
autotools dance of:

    ./configure
    make
    make install

There is also a `Dockerfile` available.

If you want to build from development sources or get involved into its
development, take a peek at the `HACKING` file.