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Shin NATORI Katsuhiko GONDOW Takashi IMAIZUMI Takeshi HAGIWARA Takuya KATAYAMA
Ordered attribute grammars (OAGs for short) are a useful class of attribute grammars (AGs). For some attribute grammars, even though they are not circular, OAG circularity test reports that they are not ordered and fails to generate attribute evaluators because some approximation introduces circularities (called type 3 circularities in this paper). First we discuss that it is sometimes difficult for programmers to eliminate type 3 circularities by hand. Second, to reduce this difficulty, we propose a new AG class called OAG* that produces less type 3 circularities than OAG while preserving the positive characteristic of OAG. OAG* uses a global dependency graph GDS that provides a new approximation algorithm. We obtained good results with our experimental implementation of OAG*. It is shown that OAG* is different from the existing GAG and Eli/Liga systems. Finally, two combinations of Eli/Liga and OAG* are provided.
Minsu KIM Kunwoo LEE Katsuhiko GONDOW Jun-ichi IMURA
The main purpose of Codemark is to distribute digital contents using offline media. Due to the main purpose of Codemark, Codemark cannot be used on digital images. It has high robustness on only printed images. This paper presents a new color code called Robust Index Code (RIC for short), which has high robustness on JPEG Compression and Resize targeting digital images. RIC embeds a remote database index to digital images so that users can reach to any digital contents. Experimental results, using our implemented RIC encoder and decoder, have shown high robustness on JPEG Comp. and Resize of the proposed codemark. The embedded database indexes can be extracted 100% on compressed images to 30%. In conclusion, it is able to store all the type of digital products by embedding indexes into digital images to access database, which means it makes a Superdistribution system with digital images realized. Therefore RIC has the potential for new Internet image services, since all the images encoded by RIC are possible to access original products anywhere.