Exploiting self-adaptive permutation-diffusion and DNA random encoding for secure and efficient image encryption.

•Self-adaptive permutation–diffusion and DNA random encoding are developed.•DNA random encoding firstly disarranges the bit distribution of the plaintext.•The quantization processes are disturbed by the intrinsic features of the plaintext.•The introduced disturbances can be automatically retrieved in the decryption end.•The reusability of the random variables dramatically promote the efficiency.