Replace a text with image.

Replace a text with image.

I'm trying to replace texts in table with pictograms. So,
$(table.classname tr td).each(function() {

});


but what to do next?

Sample td:
<td>Here is some sample text, and some more text is here.</td>

What i need is to replace all "text" words in all td's with something else ("changed" 4 example).