Local invariant feature-based methods such as SIFT have been proven highly effective for object recognition. However, they have made either relatively little use or too complex use of geometric constraints and are confounded when the detected features are superabundant. Here we make two contributions aimed at overcoming these problems. First, we rank the SIFT points (R-SIFT) using visual saliency. Second, we use the reduced set of R-SIFT features to construct a class specific hyper graph (CSHG) which comprehensively utilizes local SIFT and global geometric constraints. Moreover, it efficiently captures multiple object appearance instances. We show how the CSHG can be learned from example images for objects of a particular class. Experiments reveal that the method gives excellent recognition performance, with a low false-positive rate.

Digitization provides a solution for documentation and preservation of nonmovable cultural heritages. Despite efforts for the preservation of cultural heritages around the world, no well‐accepted metadata schema has been developed for murals and stone cave temples, which are often high‐value heritages built in ancient times. In addition, the literature is scarce on the user‐centered evaluation of metadata schemas of this kind. This study therefore aims to offer insights on developing and evaluating a metadata schema for organizing information of these historic and complex cultural heritages. In‐depth interviews were conducted with a total of 30 users, including 18 professional and 12 public users, and interview transcripts were coded through a qualitative content analysis approach. Findings reveal the importance of specific metadata elements as perceived by the two groups of end users, which correlated with their cultural heritage information‐seeking behaviors. In addition, the issues of standardization of cataloging of cultural heritage information and interoperability among metadata schemas have been raised by users for enhancing the user experience with digital platforms of cultural heritage information. The coding schema developed in this study can serve as a framework for follow‐up evaluations of metadata schemas, contributing to the ongoing development of cultural heritage metadata.

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