In recent years, there are many reversible data hiding scheme proposed. Most
schemes are guaranteed that the original cover image can be reconstructed completely.
When the secret data are hidden in the compression image, the receiver need to extract
the secret data, reconstruct the original cover image, and compress the image to save the
space. In 2006, Chang et al.  proposed a reversible data hiding scheme based on
SMVQ (Side Match Vector Quantization). Their method can extract the secret data and
reconstruct the SMVQ-compressed cover image. In this paper, we proposed a
capacity-enhanced reversible data hiding scheme. The hiding payload size of secret data
of our proposed scheme is more than that of both Chang and Wu and Chang et al.'s
schemes for VQ-based and SMVQ-based compressed images.