How to export data to base30 after ("setData","data:image/png;base64,"+base64String) successfully.

[thangvo1984]

Hi,

I have a base64 image string (for example: "iVBORw0KGgoAAAANSUhEUgAAAkQAAAEsCAYAAAAir6zwAAAgAE...")
I imported it to JSignature by code:
$('#signature').jSignature("setData","data:image/png;base64,"+base64String);
It worked fine. Image displayed successfully on JSignature.
Then I exported that image on JSignature to base30 to save to database by code:
$('#signature').jSignature('getData', "base30");
It return:
[
0: "image/jsignature;base30",
1: ""
].
Could you help me method that export data after I imported like user drawing their signature on the JSignature by themselves.

Please help me.
Thank you very much.