barefoot on A technique for hiding your JavaScript code

Comments should make it fairly straightforward to accomplish:

function foo() {

/* ...characters for image data... /

bar();

/ ...more image data... */

The asterisks are not showing up but you get the idea. It checks out with the comments part of the javascript spec as well:

...as the text inside the comment can be any unicode code unit except for an asterisk (For source Character rules see http://ecma-international.org/ecma-262/5.1/#sec-6).

If you want asterisks to show up, * put a space on both sides.

  If you want to do something *f*a*n*c*y* put two spaces
  at the front of the line, it will show up verbatim
  including line breaks.