PHP was not working for me as I was encountering this libpng issue, so I reinstalled a new version with Homebrew.
However, I\'m getting a similar error with
I had the same problem and I solved it by downloading the libjpeg tarball manuallu from here and running:
tar zxvf jpegsrc.v6b.tar.gz
cd jpeg-6b
cp /usr/share/libtool/config.sub .
cp /usr/share/libtool/config.guess .
./configure --enable-shared --enable-static
make
sudo make install
sudo ranlib /usr/local/lib/libjpeg.a #Optionally