Regex to parse image data URI

Question

If I have :

Answer 1

EDIT: expanded to show usage

var regex = new Regex(@"data:(?[\w/\-\.]+);(?\w+),(?.*)", RegexOptions.Compiled);

var match = regex.Match(input);

var mime = match.Groups["mime"].Value;
var encoding = match.Groups["encoding"].Value;
var data = match.Groups["data"].Value;

NOTE: The regex applies to the input shown in question. If there was a charset specified too, it would not work and would have to be rewritten.