First of all, never trust a benchmark which you can't reproduce. You can't reproduce lilliput-bench for the obvious reason: there are no test images. And since this is the benchmark which tests graphics codecs, results heavily depend on exact files modes and even content. So the first, what you need, is create some test data.
Now, with the installation instruction, we can start. This is my results on i5-4430 CPU (the same Haswell architecture as in the original test) and Ubuntu 18.04.1 LTS, running on bare metal. Pillow-SIMD version
5.2.0.post0 compiled with AVX2 running on Python 2.7.
JPEG 1920x1080 header read: 1920x1080, avg: 0.036190 ms min: 0.033855 ms max: 7.170200 ms PNG 1920x1080 header read: 1920x1080, avg: 0.040357 ms min: 0.038862 ms max: 0.266075 ms WEBP 1920x1080 header read: 1920x1080, avg: 0.678090 ms min: 0.149965 ms