Utilizing keywords on a picture/video based website

[Paraderain]

As we all know search engines can not read visual content, they only read text.

That being said, how does one best utilize keywords on a wordpress based website focused on pictures and videos without using keywords written in posts?

On a wordpress site, where posts usually include 1 picture/video with no text, the title being used as a catchy caption relating to the picture/video but includes no keywords...

In this situation, how does one incude keywords within these posts without including text in the posts?

To my understanding it is best to use a keyword 2 times maybe 3 times in each post, how can this be achieved in the above situation, can this be achieved with wordpress tags?

 

[Paraderain]

:bubblegum

 

[jerzydawg]

You use the tag ALT for both of them.

 

[Paraderain]

You use the tag ALT for both of them.

What exactly do you mean by tag "ALT"?

 

[jerzydawg]

http://www.perfect-optimization.com/image-alt-tags.htm

 

[Paraderain]

*link*

Not really what I am looking for to be honest, it is an option but no convenient.


It is viable to use post tags for keyword seo?