How can I convert image binary from API call to data URI in Javascript?

Question

The Google API I'm using is transmitting images only as binary data.

I have absolutly no idea how to put this into a data URI to display it, thanks for any help!

The call I'm talking about is this API call.

As you can see, it says:

The server returns bytes of the photo.

For the call (it's an extension), I use the chrome_ex_oauth methods. Maybe I need to add something into the header to get real binary data, not string as it comes in right now...

What I need to do is to convert the resulting binary into data URI so I can display it.

---

Ok, I get this out of the XHR request

Now, I dont know binary stuff much. This is somehow encoded binary data i assume? I tried to put this into btoa and other base64 encoders, everything throws an error. I tried to overrideMimeType with different things and the "response" changed in some strange ways, but nothing accepts the data.

So now I have this code:

var nxhr = new XMLHttpRequest();
nxhr.onreadystatechange = function (data) {
    if (nxhr.readyState == 4) {
        console.log(nxhr);
    }
};
nxhr.open(method, url, true);
nxhr.setRequestHeader('GData-Version', '3.0');
nxhr.setRequestHeader('Authorization', oauth.getAuthorizationHeader(url, method, params));
nxhr.send('Data to send');

Anybody else has any idea how to get this for me not understandable response into a data uri???

Thanks for any help