I got a little overwhelmed with other tasks so I can't explore this more right now though I'll try to look later. The JS package you seem to be using is genome-browser. I'd try to look at that code and any examples you can find using it.

I am not sure but it looks like you're calling the JS incorrectly and that if you fix it, you just need to print the right headers for your image data and clean up the code a bit. Sorry I'm not more help right now. :(