i have exactly the same issue:
- i understand it is hard to implement a automatic resize option to piwigo
This due to issues with sql servers who do not always support this, however this would be preferrable.
-a second best option is indeed that file limits can be set for the user upload function
(admins are suspected to be capable enough)
example options: minimum pixels longest side xxxx pixels, maximum shortest side: XXX pixels
(using the max/min longest/shortest side solves the problem of panorama's and such)