Try this (not automated, because i don't like automated delete for anything):
- Make a "smart album" in the iPhoto with the condition "Photo is Movie". With this you get all movies into your new smart album.
- press info (for check how much MB they're occupied)
- Simply drag&drop movies out of the iPhoto (long time)
- ensure (double check) they are really OK
- move the movies from the smart-album into the Trash
- empty
(triple check before deleting - do not blame me, when your computer get destroyed or so)
Well. Base on my current experiences using Jolicloud OS (http://jolicloud.com), which features a fully operational linux based personalized distribution/operating system and web apps such as Google Chrome/Chromium-Browser web application, and full access to your virtual desktop via web browser, it is possible yes.
Have a look at this: Access your Dropbox from the JoliCloud Desktop
Basically, what Jolicloud does is to link your current Dropbox account into your JoliOS service/system, after which you can gain access to your file's list (and only the list itself) and choose which of these files you wish to download/preview, etc.
From the site:
Some media files like music, photos and videos can be accessed
directly inside Jolicloud. This feature depends on the HTML5 audio and
video codecs installed in your browser. If you are using Joli OS, make
sure to install the HTML5 Video add-on to preview media files.
Illustrations from the JoliOS Blog:
This way you won't spend your disk space in storing locally your Dropbox Files/Folders but you can choose when to use them. The next screenshot is from my desktop, which is JoliOS 1.2 Installed on a 8GB SD Card running in a HP Pavilion dm4 WITHOUT Hard Disk Drive, and where you can see that my Dropbox Capacity is 11.8GB (much more than my SD Card) and in the next screenshot you will see my current SD Card available storage which is yet 2.3 GB and running like a charm.
The same behavior is applied to Google Drive.
I can't say for sure how are the JoliOS achieving this features but this wide opens the possibilities for creating new services for the Dropbox Cloud Storage.
The richest feature on the JoliCloud Service is that you can gain access to your Joli's account from technically everywhere. Only Internet and an updated web browser is required.
Good luck!
Best Answer
Open Finder and go to your Home folder (named after your User Account).
Find the Movies folder.
You can drag it into Finder's Sidebar for convenience.
In the Movies folder, you can delete anything.
Make sure to quit all programs before deleting something, so that the files are not in use. In other words, don't be listening to iTunes or whatever while you're deleting media files.
In some cases, a file may be in use, even if you've quit the relevant app. If this happens, log out and back in, or reboot the computer, then attempt to delete the files.
Be sure to empty the Trash after you delete the files, otherwise the space will not be regained.