Lossless compression ratio and Weissman score:

codec avg. compression ratio avg. space saving wavg. encode time wavg. decode time Weissman score
daala 2.798 64.26% 0.8049 0.7280 3.3381
vp9 2.905 65.58% 3.9375 0.4193 2.8011
av1-20160930 2.912 65.66% 4.7511 0.4838 2.7455
av1-20170809 2.984 66.49% 20.4157 0.6900 2.4003
kdu 1.564 36.06% 0.3875 0.2892 2.0946
jxr 1.560 35.89% 0.4058 0.3628 2.0730
av1-20180222 2.943 66.02% 97.6492 1.0156 2.0444
flif 2.473 59.57% 22.1088 4.3042 1.9732
openjpeg 1.564 36.06% 2.1181 1.3794 1.6300
webp 2.124 52.93% 37.9675 2.4799 1.6079
bpg 1.150 13.03% 3.7503 3.5251 1.1151
mozjpeg 1.137 12.05% 8.7385 0.4144 1.0000

Lossy compression and speed

Encoding time in function of bits per pixel