javascript check if img src is valid?

I have something like:

document.getElementById('MyPicture').src = 'attempted.png';

If the client cannot get that resource, I would like to replace it with:

document.getElementById('MyPicture').src = 'error.png'

I know I can put onError=function() in the image tag, but how can I pass the Id to onError, so that I can have one onError function that can change the src of any bad pics?