Differences With Original Guetzli

PyGuetzli is and will always be as close as possible to original Guetzli library from Google, with the exception of two things (patched in the Guetzli source code):

• We needed to add the -fPIC flag to the build of the static library to allow it to be linked with our code. See commit 467cb04.

• By default Guetzli do not accepts to generates JPEGs with a quality under 84. As we needed to generate poor quality JPEGs, we removed this limitation. See commit ebe4840.

• Guetzli: Fixed a crash caused by a bad access to a vector revealed when compiled with -D_GLIBCXX_ASSERTIONS. See commit 1c35835.