oxipng — oxipng.exe -o 6 --libdeflater --alpha --strip all

file insize instate stats outsize outstate savings
lorem.png 135614 bytes /c2 /f0 /n63
Kernel  Time =     0.015 =    2%
User    Time =     2.640 =  489%
Process Time =     2.656 =  492%    Virtual  Memory =     67 MB
Global  Time =     0.539 =  100%    Physical Memory =     39 MB
105679 bytes /c2 /f0 /n16 29935 bytes
lorem_90.png 483089 bytes /c2 /f0 /n106
Kernel  Time =     0.046 =   10%
User    Time =     2.062 =  450%
Process Time =     2.109 =  460%    Virtual  Memory =     67 MB
Global  Time =     0.458 =  100%    Physical Memory =     27 MB
451970 bytes /c2 /f0 /n56 31119 bytes
lorem_big.png 127451 bytes /c2 /f0 /n3
Kernel  Time =     0.031 =    4%
User    Time =     2.500 =  332%
Process Time =     2.531 =  336%    Virtual  Memory =     66 MB
Global  Time =     0.751 =  100%    Physical Memory =     28 MB
68797 bytes /c0 /f0 /d8 /n26 58654 bytes
lorem_big_16.png 65084 bytes /c0 /f0 /d8 /n28
Kernel  Time =     0.046 =    8%
User    Time =     2.328 =  420%
Process Time =     2.375 =  428%    Virtual  Memory =     63 MB
Global  Time =     0.553 =  100%    Physical Memory =     35 MB
46626 bytes /c0 /f0 /d8 /n12 18458 bytes
lorem_big_17.png 65551 bytes /c0 /f0 /d8 /n35
Kernel  Time =     0.031 =    5%
User    Time =     2.250 =  403%
Process Time =     2.281 =  409%    Virtual  Memory =     63 MB
Global  Time =     0.557 =  100%    Physical Memory =     35 MB
45954 bytes /c0 /f0 /d8 /n13 19597 bytes
lorem_big_noise.png 823706 bytes /c2 /f0 /n82
Kernel  Time =     0.015 =    0%
User    Time =    10.390 =  461%
Process Time =    10.406 =  462%    Virtual  Memory =     83 MB
Global  Time =     2.250 =  100%    Physical Memory =     64 MB
613790 bytes /c2 /f0 /n59 209916 bytes
lorem_gray.png 140439 bytes /c2 /f0 /n123
Kernel  Time =     0.015 =    4%
User    Time =     1.171 =  312%
Process Time =     1.187 =  317%    Virtual  Memory =     60 MB
Global  Time =     0.374 =  100%    Physical Memory =     33 MB
56668 bytes /c0 /f0 /d8 /n6 83771 bytes
lorem_image.png 133069 bytes /c2 /f0 /n3
Kernel  Time =     0.000 =    0%
User    Time =     4.468 =  512%
Process Time =     4.468 =  512%    Virtual  Memory =     78 MB
Global  Time =     0.871 =  100%    Physical Memory =     49 MB
117411 bytes /c2 /f0 /n33 15658 bytes
lorem_noise.png 542244 bytes /c2 /f0 /n67
Kernel  Time =     0.031 =    2%
User    Time =     4.750 =  447%
Process Time =     4.781 =  450%    Virtual  Memory =     70 MB
Global  Time =     1.061 =  100%    Physical Memory =     38 MB
428159 bytes /c2 /f0 /n84 114085 bytes
lorem_pal.png 121950 bytes /c2 /f0 /n73
Kernel  Time =     0.000 =    0%
User    Time =     1.203 =  319%
Process Time =     1.203 =  319%    Virtual  Memory =     60 MB
Global  Time =     0.376 =  100%    Physical Memory =     35 MB
51835 bytes /c0 /f0 /d8 /n6 70115 bytes
total savings 651308 bytes
total time 7,79 seconds