The first
three we can get from pretty much either API, or extract
directly from
a dump file. The latter is eluding us though, for
two reasons. One is
that a
file, like 30C3_Commons_Machinery_2.jpg, is
actually in the /b/ba/
directory -
but where this /b/ba/ comes from (a hash?) is
unclear to us now, and
it's not
something we find in the dumps - though we can
get it from one of the
APIs.
Yes, /b/ba ist based on the first two digits of the MD5 hash of the title:
md5( "30C3_Commons_Machinery_2.jpg" ) -> ba253c78d894a80788940a3ca765debb
But this is "arcane knowledge" which nobody should really rely on. The
canonical
way would be to use
To get a thumbnail, you can directly manipulate that URL, by inserting
"thumb/"
and the desired size in the correct location (maybe Special:Redirect can
do that
for you, but I do not know how):