Comparison results of 2D Monogenic Pure Context Free Picture Grammars with other relating models

Picture languages generated by array grammars or accepted by array automata have been studied by researchers and various models have been proposed in the literature, motivated by problems arising in the framework of syntactic methods of pattern recognition and image processing. The notion of Pure 2D Picture Grammars, generating rectangular picture arrays of symbols is already there in the literature. In this paper, we introduce another notion called 2D Monogenic Pure Context-free Picture Grammars and Compare its generative power with other related models. We have also obtained certain closure properties and shown that this class is polynomial-time identifiable in the limit from positive data.