gimp single channel
Intel Core i7-7700 testing with a Gigabyte B250M-D3H-CF and Intel Kabylake GT2 3072MB on Debian 9.1 via the Phoronix Test Suite.
HTML result view exported from: https://openbenchmarking.org/result/1707263-TR-GIMPSINGL84.
GIMP
Test: resize
GIMP
Test: auto-levels
GIMP
Test: unsharp-mask
Phoronix Test Suite v10.8.4