image base64 to file javascript

1 function dataURLtoFile(dataurl, filename) {
2 
3        var arr = dataurl.split(','),
4            mime = arr[0].match(/:(.*?);/)[1],
5            bstr = atob(arr[1]), 
6            n = bstr.length, 
7            u8arr = new Uint8Array(n);
8            
9        while(n--){
10            u8arr[n] = bstr.charCodeAt(n);
11        }
12        
13        return new File([u8arr], filename, {type:mime});
14    }
15    
16    //Usage example:
17    var file = dataURLtoFile('data:text/plain;base64,aGVsbG8gd29ybGQ=','hello.txt');
18    console.log(file);