I am building a website for a client, and he needs some software to be able to add watermarks too, and slightly compress for bandwidth on his website. I'm struggling to find a solution that does both of these things.
Does anyone know of anything?
You can do this work with Batch Convert functionality of XnView MP. As first step you select the images you want to manage, then filters/actions (resize, watermark), where to store the result and voila. Below is an image of program interface with resize and watermark plugins loaded:
NB! No affiliate with mentioned software.
The canonical utility for batch image processing is ImageMagick. Its
convert command/component can change format, change compression parameters, and add text to a picture. It is free, open source, and can be used either as a command-line utility or as a library with binding for all major languages (Java, PHP, Python...).