Watermarking for multi-stage encoded image authentication

Abstract

Multi-stage encoded images generally provide multiple resolutions that have advantages in image transmission and storage. Several image encoders such as JPEG, SPIHT, EZW, JPEG2000, etc. support multi-stage encoding. However, any one of multi-stage encoded images should also be authentic to ensure transmission security. In this paper, a watermarking-based authentication scheme for multi-stage encoded images is proposed. The image authentication message is extracted from the image content and then embedded into images according to the multi-stage encoding. The experimental results show the validity of the proposed multi-stage image authentication scheme. A malicious operation can be detected within a multi-stage encoded image in which any significant tampering can be detected in the earlier authentication stages and any slight tampering can be detected in the later authentication stages. Furthermore, the proposed scheme can distinguish acceptable operations from malicious manipulations and the positions of the tampered areas can be located.