Selective Encryption of Human Skin in JPEG Images

In this study we propose a new approach for selective encryption in the Huffman coding of the discrete cosine transform (DCT) coefficients using the advanced encryption standard (AES). The objective is to partially encrypt the human face in an image or video sequence. This approach is based on the AES stream ciphering using variable length coding (VLC) of the Huffman´s vector. The proposed scheme allows the decryption of a specific region of the image and results in a significant reduction in encrypting and decrypting processing time. It also provides a constant bit rate while maintaining the JPEG and MPEG bitstream compliance.