We have implemented the signature widget and want to convert the signature into a Mendix image. How can we achieve this? We already created a derivative of the system.image entity and used the Java function Base64DecodeToFile from the Community Commons library. The result however is not an image that the image widget understands.
The trick is that the start of the image encoded image is only needed to show it as picture in the browser. It is not needed in the Image conversions.
To solve the issue you need to remove the first 22 characters on the string, just before put in the encoding java action.