Base64EncodesourceField - the name of a field.Base64Encode(Products::Color) returns QmxhY2s= when Products::Color is set to "Black".Base64Encode(Products::Container) returns a string that begins with iVBORw0KGgoAAAANSUhEUgAAAB8 when Products::Container is set to . The Base64 string in this example was shortened for readability.