4D allows you to save the data that you create with a plug-in such as 4D Draw, 4D Chart or 4D Write into a picture or a BLOB field. The only restriction that you have to follow is that the name of the picture or BLOB field must be a combination of the variable name of the plug-in area and "_".
e.g. variable name = Plug-in Area1
picture field = Plug-in Area1_