Alvaro Herrera <alvherre@commandprompt.com> writes:
> Do you mean you actually find stuff based on text attributes in JPEG
> images and the like? I thought those were compressed ...
Typically not --- the design assumption is that the text size wouldn't
amount to anything anyway compared to the image data, and it's better to
be able to pull it out with minimal processing.
I do suggest though that an image containing auxiliary data like text
comments is a multi-part structure, and that dumping it into a single
uninterpreted database field is spectacularly bad schema design.
You should pull the text out into a separate column once when you store
the data, instead of trying to fix things up when you search.
regards, tom lane