ABSTRACT
This chapter presents different techniques used for recovery in the frequency domain and provides pros and cons of different technologies in fragile watermarking with recovery capabilities. It details the fragile watermarking algorithms with recovery capabilities in the frequency domain, identifies the research gap and research interest in this field and explores their own scheme in MATLAB. In fragile watermark schemes with recovery capabilities in the frequency domain, summary bits are generated by using the frequency coefficients of the image. The chapter shows that fragile watermarks with recovery capabilities in the frequency domain can be broadly classified in two ways: on the basis of the embedding mechanism and on the basis of the extraction mechanism. In case of recovery in the frequency domain, pixel-based recovery with block-based authentication is possible which is difficult in the case of recovery in the spatial domain.
