Image Processing in Encrypted Domain:a Comprehensive Survey

With the ever increasing concern of privacy security,signal processing in encrypted domain has drawn considerable attentions.Since an image often contain much personal and privacy information,it is also necessary to process images in a privacy protection manner.This article reviewed the recent advances in secure image processing in a variety of fields,including fundamental image processing techniques like linear transforms,linear filtering and feature extraction in encrypted domain and further image processing applications like secure image data hiding,secure image retrieval and encrypted image compression.The future research trends and prospects in these directions were also presented in this article.