70d firmware upgrade? File male prefix.

Hi all,
I read in Outdoor Photographer how to change the file name prefix on the 5D mark 3. I want to do the same on my 70d.

A search here on POTN found that the 7D firmware upgrade included the ability to put in a prefix on the 7d.

As far as I see there is not a firmware upgrade for the 70d. ( I checked the sticky).

Does anyone know how to change the file name prefix on the 70d? Going forward, it would be nice to automatically flag the camera body in the image file name.

Thanks.

You sure you want a "file male prefix" on your photos?

For cameras where this isn't available, you have to do it when you transfer the images from the camera to your computer.
Currently, Canon keep this feature in the more advanced range of cameras.