Convert PNG image binary string to base64 with Javascript/JQuery [duplicate]

Question

I'm newbie on this but I have this problem, I'm using an API which gives me as result a PNG image binary string:

I want to convert this to base64 and put it as an attribute in an img tag

<img id="ml">

So tried, doing this:

$("#ml").attr("src",'data:image/png;base64,'+ btoa(unescape(encodeURIComponent(response))) );

But this shows me a broken image:

I tried with this getting the same error:

var blob = new Blob([response], {type: 'image/png'});
var reader = new FileReader();

reader.onload = function (e) {
  $('#ml').attr('src', e.target.result);
};

reader.readAsDataURL(blob);

Finally I used a library: https://github.com/dankogai/js-base64

var emk = Base64.encode(response);
$("#ml").attr("src",'data:image/png;base64,'+ emk );

But the result is the same.

I don't know if I'm missing something, I'd like to receive your help.

=====

UPDATE:

As you mentioned in the comments I mention the previous step:

I obtain this binary result from VanceAI API. I upload an image, then process applying an edition provided by API service and finally the result is for download, this is the code:

var form = new FormData();
    form.append("api_token", "XXXXXXX1234AAAAAA");
    form.append("trans_id", "XXXXBBBBVVVVVVVV"); //processed image ID

    var settings = {
      "url": "https://api-service.vanceai.com/web_api/v1/download?api_token=XXXXXXX1234AAAAAA",
      "method": "POST",
      "timeout": 0,
      "processData": false,
      "mimeType": "multipart/form-data",
      "contentType": false,
      "data": form
    };

    $.ajax(settings).done(function (response) {
            console.log(response); // binary result
    });

I also tried this:

$("#ml").attr("src",'data:image/png;base64,'+ btoa(response) );

But I get this error:

I also have to mention this result is not a Blob.

I hope you can help me.

Thanks.