libjpeg-turbo is very fast

I recently discovered libjpeg-turbo, a drop-in replacement for the venerable libjpeg.so.62 that uses SIMD instructions to achieve 2–4x the performance of the old library.

I downloaded, built, and installed it (putting it first in LD_LIBRARY_PATH), and was pleasantly surprised to find it working exactly as advertised. I have conducted only a few informal tests on large images, but it's clearly a great deal faster.