JPEG image encryption using fuzzy PN sequences

Abstract

The recent explosion in multimedia and networking application places a great demand on efficient transmission of images at low bit rate with high security. Mixing several existing standard encryption techniques with image encoding tends to change the compression ratio greatly. In this paper, a novel image encryption algorithm is embedded as a part of JPEG image encoding scheme to meet three major necessities: (1) to provide temporal security against casual observer, (2) to preserve the compression ratio, (3) remain compliant with the JPEG file format. In the proposed algorithm, the modified DCT blocks are confused by a fuzzy PN sequence. In addition to that, the DCT coefficients of each modified DCT block are converted to unique uncorrelated symbols, which are confused by another fuzzy PN sequence. Finally, the variable length encoded bits are encrypted by chaotic stream cipher. An amalgamation of all the three techniques with random combination of seeds will provide the required security against the casual listener/observer where the security needed is only in-terms of few hours.

A Non-format Compliant Scalable RSA-based JPEG Encryption Algorithm

“…The special nature of the JPEG encoding process makes JPEG-related algorithms a class apart from those applied to other image formats. There are two broad categories of JPEG encryption--format-compliant [4][5] [9][10] and nonformat-compliant. In the former case, the encryption algorithm is bound by the restriction that the encrypted output must conform to the JPEG algorithm and format.…”

“…In the latter case, there is no such restriction and hence, these class of algorithms can afford to be much more flexible and inventive. Format-compliant algorithms usually are based on shuffling of DC coefficients [Niu et al,5], randomly shuffling the signs of the AC coefficients, a combination of several scrambling and shuffling operations using the XOR operation [12], a combination of several operations at the bit stream level [4], permutation of the zigzag scheme used in JPEG encryption [11] or the use of fuzzy PN sequences [9].…”

A Robust Chaotic and Fast Walsh Transform Encryption for Gray Scale Biomedical Image Transmission

“…[12] and improved encryption method based on two dimensional Fourier Transform, crossover operation and the use of a keyed mutation function. In [13], B.K. Shreyamshakumar et al showed that, image cryptosystem usually manipulates an entire data set without any presumption about compression at later time; consequently, the secure transmission of image has become more costly in term of time, bandwidth and complexity.…”

JPEG image Encryption via TEA algorithm

“…JPEG ag iletişimi, kablosuz haberleşme, medikal, multimedya ve özellikle gömülü sistemlerde çogunlukla kullanılmaktadır [2]. Günümüz teknolojisinde, ücretli televizyon yayınları, özel video konferanslar, medikal görüntüleme, endüstriyel ve askeri görüntüleme gibi uygulamalarda sayısal görüntü ve videoların güvenligi büyük bir önem kazanmıştır [3].…”