optipng(1) on Linux
The text b1861b5b8cf3, as Debian 7 (Wheezy), Debian 6.0 (Squeeze) shipped it.
Advanced optimization program for Portable Network Graphics (PNG)
Flags it lists
-
-- -
-? -
-dir -
-f -
-fix -
-force -
-full -
-h -
-help -
-i -
-keep -
-log -
-nb -
-nc -
-np -
-nx -
-nz -
-o -
-out -
-preserve -
-quiet -
-simulate -
-snip -
-v -
-verbose -
-version -
-zc -
-zm -
-zs -
-zw