Same base64 decoders doesn't work, when there are end of string characters in base64 encoded data.
If you can't obtain image or pdf from base64encoded string, obtained from AnyChart Stock swf using Java Script methods
, try to remove line breaks from the string.
For example, in export helper for Java we use this code:
base64String = base64String.replaceAll("\r","").replaceAll("\n","");