—The pervasive distribution of digital images triggers an emergent need of authenticating degraded images by lossy compression and transmission. This paper proposes a robust content-based image authentication scheme for image transmissions over wireless channels. A robust multiscale based feature is used to generating digital signature. The feature vector is reduced, encoded, and encrypted as signature of the image. This signature is then embedded into the image using a blind quantization based watermarking algorithm. Typical distortion patterns of malicious image manipulations and image transmissions over lossy channels are used for image authenticity verification. This scheme is also able to detect tampering areas in the attacked image. Experiments demonstrate the effectiveness and validity of our scheme.