A novel reversible data hiding in encrypted domain is proposed based on block sorting and histogram modification. The first work divides image into blocks and blocks sorting

and each block is permuted by scrambling encryption. Then

the histogram of each block is modified to vacate room for secret data. Finally

the receiver can decrypt firstly and then extract data

the inverse process is also viable. Experiments show that the operator of data extraction and image decryption is completely separable in the proposed method

and compared with the existing methods

the proposed method has improved embedding capacity while maintaining zero error rate

and has better image quality while under-capacity.