To use fragile/semi-fragile digital watermarking for image authentication, fragility of the embedded watermark to the
malicious attacks is very important to illustrate the authentication degree. A fragile/semi-fragile watermarking scheme
should be sensitive to any modifications or malicious attacks, while semi-fragile watermarking accepts some incidental
manipulations, such as JPEG compression. The binary phase-only filter (BPOF) based watermarking proposed by F.
Ahmed et al., takes the BPOF of the Fourier spectrum of an image as the watermark and embed it into the corresponding
magnitude. The authors claimed that the method is a semi-fragile watermarking since it can resist some image processing
manipulations. However, they did not discuss the fragility of the technique to the malicious attacks, such as image
tampering. In this paper, we analyzed the fragility of the binary phase-only based digital image watermarking via
experiments and concluded that this technique works better for fragile watermarking than for semi-fragile watermarking.