What is the ruling on using gelatin extracted from pigs or from animals not slaughtered according to Islamic law?

Gelatin is a substance extracted from animal bones and tissues, and it is used in many food and pharmaceutical industries. It is permissible to extract gelatin from animals that are lawful and slaughtered according to Islamic law, or from non-harmful plants. However, it is forbidden to extract it from pigs or from animals that have not been slaughtered according to Islamic law. If gelatin is extracted from an impure source (عين نجسة), scholars have differed regarding the ruling on consuming it after processing: some are of the view that it becomes permissible through complete transformation (استحالة كاملة), while others believe that the transformation is not complete, and the ruling of prohibition remains. This latter view, which leans towards prohibition, is particularly evident given the availability of permissible alternatives.