Which will boost a search engine optimization campaign: setting your content to creative common licence or copy-write protection of your content? and to what extent to they influence the SEO campaign?
Search engine algorithms don't know anything about content licenses, so there is no direct SEO effect (positive or negative).
However, search engines do weed out duplicate content, so when it sees two pages with the same content, one will typically get dropped from search results.
If your content is already indexed in search engines this is not a problem. If the content is new and you license it (even with attribution), a more popular site could post the content and your page could get marked as the duplicate.
So if you feel that a CC license will increase the buzz around your site, go for it.
A CC BY-SA Attribution-ShareAlike or Similar can help SEO
Using CC can boost SEO but as DisgruntledGoat mentioned its important to know that your page could be marked duplicate if a big site comes along and uses your images before your page is indexed. So if your going to proceed with CC you want your site being indexed as quickly as possible, a big site may get updates within an hour, if your site is on average 5 days then a big site subscribing to your RSS feed could potentially gain SEO for being the master for the image and then you marked as the duplicate. Now you could explore ways of saying... this is closed licensed for X days but again, I don't think they'll stop people since most people just think the whole site is CC and asking them to remove it will do nothing since you're already be marked as the dupe.
Now lets take a look at the license CC BY-SA
Now the important thing to take note off is what I put in bold which is
So you can gain backlink's, great hey? well not always
Most people will assume that the more natural back links they have the better, but this isn't always the case, yes natural back links are key but the relevance of them is key. For example if your site is about
So yes CC can help SEO but as pointed out by DisgruntledGoat it can have a negative effect if your side is not being indexed quickly and people use your images that are indexed quickly, additionally using generic images can dilute your authority so if your site is about CARS only license pictures with CARS and hope they back link from other car sites or mention your brand as I mentioned.