How to bulk resize images imported with feeds importer module?
If you have access to a command line and ImageMagick, you can run convert from find.
In Unix et al
From Drupal root:
find sites/default/files/products -name '*.jpg' -execdir convert {} -resize 700x400 {}\;
(Note: this assumes all product images are in the &quot;products&quot; directory in sites/default/files. You DO want to make a copy of this directory with cp -r sites/default/files/products sites/default/files/products_backup before running the above in case it does something you don't want it to!)
In Windows:

Download and install findutils.
Download and install ImageMagick
Make sure both are working on the commandline. Type &quot;find&quot; and hit enter. Same with &quot;convert&quot;. If neither gives you a &quot;command not found&quot; error, they're installed and working.
Backup your product images directory.
Instead of the above command, try:

find sites\default\files\products -name '*.jpg' -execdir convert '{}' -resize 700x400 '{}' ';'
If find chokes on that path, try using backslashes. Also, make sure it's using the GNU version of find and not some other version (The lender Windows machine I'm working on right now has a find command, don't know if that's standard or something somebody else installed).