In this paper, we establish a framework of delta-sigma conversion of graph signals. First, we define delta-sigma conversion for graph signals by considering the corresponding conversion for standard time series signals. We next propose a conversion method based on spanning in-tree, for which it is proven that the method satisfies the conditions for delta-sigma conversion. The proposed method is demonstrated by numerical examples and application to halftone image processing.
This work was partly supported by Grant-in-Aid for Challenging Exploratory Research #16K14283 from the Ministry of Education, Culture, Sports, Science, and Technology of Japan.
