Watermarking schemes for authentication purposes are characterized by three factors: security, resolution of tamper localization, and embedding distortion. Since the requirements of high secudty, high localization resolution, and low distortion cannot be fulfilled simultaneously, the relative importance of a particular factor is application-dependent. Moreover, blockwise dependence is recognized as a key requirement for fragile watermarking schemes to thwart the Holliman-Memon counterfeiting attack. However, it has also been observed that deterministic dependence is still susceptible to transplantation attack or even simple cover-up attack. This work proposes a fragile watermarking scheme for image authentication, which exploits nondeterministic dependence and provides the users with freedom of making trade-offs among the three factors according to the needs of their applications.