# A Selective Video Encryption Scheme Based on Coding Characteristics

^{1}

^{2}

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Description of Video Encryption Scheme Based on H.264/AVC

#### 2.1. H.264/AVC Bit-Stream Syntax Structure

#### 2.2. Pseudo Random Sequence Generator

_{1}and R

_{2}are two 32-bit memory cells, and F

_{1}and F

_{2}are two chaotic functions, respectively. PRNG execution produces a 32-bit Z at a time, which forms the output of the key stream by combining 32-bit Z. Literature [25] suggests that PRNG discards the first 100 values and uses post-order values, given the security of the password.

#### 2.3. AES Encryption Algorithms

_{i}and the ciphertext block C

_{i}is as follows:

#### 2.4. The Four-Dimensional Hyperchaotic System

_{1}, y

_{2}, y

_{3}, y

_{4}).

## 3. Video Selective Encryption Scheme

#### 3.1. Selection of Important Syntax Elements

_{d}= mv − mv’. In the H.264/AVC baseline profile, the MVD is encoded while using Exp-Golomb entropy coding. The value of MVD and the corresponding Exp-Golomb codeword is indicated in the paper [28], and the last bit of the Exp-Golomb codeword is given to affect the MVD symbol. Therefore, we only need to encrypt the last bit of the Exp-Golomb codeword in the motion vector difference.

#### 3.2. Selective Encryption Process

#### 3.3. Decryption Process

#### 3.4. Introduce 4-D Hyperchaotic Selective Video Encryption Process

## 4. Experimental Results and Analysis

#### 4.1. Security Analysis of Selective Video Encryption Scheme

#### 4.1.1. Subjective Video Quality Analysis

#### 4.1.2. Objective Video Quality Analysis

#### 4.2. Evaluation Comparison

#### 4.3. Security Analysis

#### 4.3.1. Key Volume

#### 4.3.2. Security Analysis of Selective Video Encryption Scheme

## 5. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

- Guang, M.A.; Zhao, P.J.; Cui, M.X. Research and Implementation of Medical Video Encryption and Decryption Player. China Med. Devices
**2016**, 6, 87–89. [Google Scholar] - Schwarz, H.; Marpe, D.; Wiegand, T. Overview of the scalable video coding extension of the H. 264/AVC standard. IEEE Trans. Circuits Syst. Video Technol.
**2007**, 17, 1103–1120. [Google Scholar] [CrossRef] [Green Version] - Lian, S. Multimedia Content Encryption: Techniques and Applications; Auerbach Publications: New York, NY, USA, 2008. [Google Scholar]
- Ahn, J.; Shim, H.J.; Jeon, B.; Choi, I. Digital video scrambling method using intra prediction mode. In Proceedings of the 5th Pacific Rim Conference on Multimedia, Tokyo Waterfront City, Japan, 30 November–3 December 2004; pp. 386–393. [Google Scholar]
- Khlif, N.; Damak, T.; Kammoun, F.; Masmoudi, N. A very efficient encryption scheme for the H.264/AVC CODEC adopted in Intra prediction mode. In Proceedings of the International Image Processing, Applications and Systems Conference, Sfax, Tunisia, 5–7 November 2014; pp. 1–7. [Google Scholar]
- Khlif, N.; Damak, T.; Kammoun, F.; Masmoudi, N. Motion vectors signs encryption for H.264/AVC. In Proceedings of the 2014 1st International Conference on Advanced Technologies for Signal and Image Processing, Sousse, Tunisia, 17–19 March 2014. [Google Scholar]
- Lian, S.; Liu, Z.; Ren, Z.; Wang, Z. Selective video encryption based on advanced video coding. In Proceedings of the 6th Pacific Rim Conference on Multimedia, Jeju Island, Korea, 13–16 November 2005; pp. 281–290. [Google Scholar]
- Lian, S.; Liu, Z.; Ren, Z.; Wang, H. Secure advanced video coding based on selective encryption algorithms. IEEE Trans. Consum. Electron.
**2006**, 52, 621–629. [Google Scholar] [CrossRef] - Shi, T.; King, B.; Salama, P. Selective encryption for H.264/AVC video coding. In Proceedings of the SPIE Security, Steganography, and Watermarking of Multimedia Contents VIII, San Jose, CA, USA, 15 January 2006; p. 607217. [Google Scholar]
- Jiang, J.; Liu, Y.; Su, Z.; Zhang, S.; Xing, S. An Improved Selective Encryption for H.264 Video based on Intra Prediction Mode Scrambling. J. Multimed.
**2010**, 5, 464–472. [Google Scholar] [CrossRef] - Sbiaa, F.; Kotel, S.; Zeghid, M.; Tourki, R.; Machhout, M.; Baganne, A. A Selective Encryption Scheme with Multiple Security Levels for the H.264/AVC Video Coding Standard. In Proceedings of the 2016 IEEE International Conference on Computer and Information Technology (CIT), Nadi, Fiji, 8–10 December 2016. [Google Scholar]
- Khlif, N.; Masmoudi, A.; Kammoun, F.; Masmoudi, N. Secure chaotic dual encryption scheme for H.264/AVC video conferencing protection. IET Image Process.
**2018**, 12, 42–52. [Google Scholar] [CrossRef] - Asghar, M.N.; Ghanbari, M.; Fleury, M.; Reed, M.J. Confidentiality of a selectively encrypted H.264 coded video bit-stream. J. Vis. Commun. Image Represent.
**2014**, 25, 487–498. [Google Scholar] [CrossRef] - Shahid, Z.; Chaumont, M.; Puech, W. Fast protection of H.264/AVC by selective encryption of CABAC. In Proceedings of the 2009 IEEE International Conference on Multimedia and Expo, New York, NY, USA, 28 June–3 July 2009; pp. 1038–1041. [Google Scholar]
- Radanliev, P.; De Roure, D.C.; Nicolescu, R.; Huth, M.; Mantilla, M.; Canaday, S.; Burnap, P. Future developments in cyber risk assessment for the internet of things. Comput. Ind.
**2018**, 102, 14–22. [Google Scholar] [CrossRef] - Radanliev, P.; De Roure, D.C.; Nurse, J.R.C.; Montalvo, R.M.; Canady, S.; Santos, O.; Maddox, A.; Burnap, P.; Maple, C. Future developments in standardisation of cyber risk in the Internet of Things (IoT). SN Appl. Sci.
**2020**, 2, 169. [Google Scholar] [CrossRef] [Green Version] - Nicolescu, R.; Huth, M.; Radanliev, P.; Roure, D. Mapping the values of IoT. J. Inf. Technol.
**2018**, 33, 345–360. [Google Scholar] [CrossRef] [Green Version] - Zhu, Z.; Zhang, W.; Wong, K.W.; Yu, H. A chaos-based symmetric image encryption scheme using a bit-level permutation. Inf. Sci.
**2011**, 181, 1171–1186. [Google Scholar] [CrossRef] - Ravichandran, D.; Praveenkumar, P.; Balaguru Rayappan, J.B.; Amirtharaja, R. Chaos based crossover and mutation for securing DICOM image. Comput. Biol. Med.
**2016**, 72, 170–184. [Google Scholar] [CrossRef] [PubMed] - Cheng, S.L.; Wang, L.J.; Huang, G.; Du, A.Y. A privacy-preserving image retrieval scheme based secure kNN, DNA coding and deep hashing. Multimed. Tools Appl.
**2019**, 1–23. [Google Scholar] [CrossRef] - Cheng, S.; Wang, L.; Du, A. Histopathological image retrieval based on asymmetric residual hash and DNA coding. IEEE Access
**2019**, 7, 101388–101400. [Google Scholar] [CrossRef] - Hamidouche, W.; Farajallah, M.; Raulet, M.; Deforges, O.; Assad, S.E. Selective video encryption using chaotic system in the SHVC extension. In Proceedings of the 2015 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Brisbane, Australia, 19–24 April 2015. [Google Scholar]
- Altaf, M.; Ahmad, A.; Khan, F.A.; Uddin, Z.; Yang, X. Computationally efficient selective video encryption with chaos based block cipher. Multimed. Tools Appl.
**2018**, 77, 27981–27995. [Google Scholar] [CrossRef] - Wiegand, T.; Sullivan, G.J.; Bjontegaard, G.; Luthra, A. Overview of the H.264/AVC video coding standard. IEEE Trans. Circuits Syst. Video Technol.
**2003**, 13, 560–576. [Google Scholar] [CrossRef] [Green Version] - Xu, H.; Tong, X.; Meng, X. An efficient chaos pseudo-random number generator applied to video encryption. Optik
**2016**, 127, 9305–9319. [Google Scholar] [CrossRef] - Shukla, P.K.; Khare, A.; Rizvi, M.A.; Stalin, S.; Kumar, S. Applied cryptography using chaos function for fast digital logic-based systems in ubiquitous computing. Entropy
**2015**, 17, 1387–1410. [Google Scholar] [CrossRef] [Green Version] - Van Wallendael, G.; Boho, A.; De Cock, J.; Munteanu, A.; Van De Walle, R. Encryption for high efficiency video coding with video adaptation capabilitie. IEEE Trans. Consum. Electron.
**2013**, 59, 634–642. [Google Scholar] [CrossRef] [Green Version] - Xu, D.; Wang, R.; Shi, Y.Q. Data Hiding in Encrypted H.264/AVC Video Streams by Codeword Substitution. IEEE Trans. Inf. Forensics Secur.
**2014**, 9, 596–606. [Google Scholar] [CrossRef] - Richardson, I.E.G. H.264 and MPEG-4 Video Compression: Video Coding for Next Generation Multimedia; Wiley: Hoboken, NJ, USA, 2003. [Google Scholar]
- Khlif, N.; Damak, T.; Kammoun, F.; Masmoudi, N. Selective encryption of CAVLC for H.264/AVC. In Proceedings of the 14th International Conference on Sciences and Techniques of Automatic Control & Computer Engineering—STA’2013, Sousse, Tunisia, 20–22 December 2013. [Google Scholar]
- Abomhara, M.; Zakaria, O.; Khalifa, O.O.; Zaidan, A.A.; Zaidan, B.B. Enhancing Selective Encryption for H. 264/AVC Using Advanced Encryption Standard. Int. J. Comput. Electr. Eng.
**2010**, 2, 223–229. [Google Scholar] [CrossRef] - Shahid, Z.; Chaumont, M.; Puech, W. Fast protection of H.264/AVC by selective encryption of CAVLC and CABAC for I and P frames. IEEE Trans. Circuits Syst. Video Technol.
**2011**, 21, 565–576. [Google Scholar] [CrossRef] - Peng, F.; Zhu, X.; Long, M. An ROI Privacy Protection Scheme for H.264 Video Based on FMO and Chaos. IEEE Trans. Inf. Forensics Secur.
**2013**, 8, 1688–1699. [Google Scholar] [CrossRef] - Sung-Sam, H.; Myung-Mook, H. The study of selective encryption of motion vector based on the S-Box for the security improvement in the process of video. Multimed. Tools Appl.
**2014**, 71, 1577–1597. [Google Scholar] - Wei, Z.; Wu, Y.; Ding, X.; Deng, R.H. A scalable and format-compliant encryption scheme for H.264/SVC bitstreams. Signal Process. Image Commun.
**2012**, 27, 1011–1024. [Google Scholar] [CrossRef] - Wang, X.; Zheng, N.; Tian, L. Hash key-based video encryption scheme for H: 264/AVC. Signal Process. Image Commun.
**2010**, 25, 427–437. [Google Scholar] [CrossRef]

**Figure 1.**Data hierarchy in a video stream. Figure 1 contains three different types of frames (I-frame, P-frame and B-frame). Among them, I frames are encoded independently of other images. P-frames are encoded using the predictions of previous I or P-frames. B frames use double prediction of the previous and next I or P frames. The GOP sequence takes I frame as a start frame, and it is a periodic sequence. Each frame is sliced to limit error transmission.

**Figure 2.**Working mode of Pseudo-random number generator (PRNG). PRNG contains three logical layers (top, middle, and bottom). The top layer consists of 16 linear feedback shift registers, the middle layer is a bit recombination layer, and the bottom layer is a non-linear mapping layer.

**Figure 3.**The working mode of CFB. Figure 3a CFB mode encryption. The encryption process requires a shift register that is the same size as the block to initialize the register. Then, the contents of the register are encrypted using a block cipher. Figure 3b CFB mode decryption. Based on Exclusive OR (XOR) operation, CFB mode decryption can be implemented.

**Figure 4.**Encryption flow chart. Figure 4 is selective video encryption, which mainly encrypts important elements in the video slice. At the same time, there is independence between video slices.

Video Sequence | Video Size | Encoded Video Size | Encrypted Video Size | Decrypted Video Size |
---|---|---|---|---|

coastguard | 10.8 KM | 444 K | 444 K | 444 K |

containe | 10.8 KM | 251 K | 251 K | 251 K |

foreman | 10.8 KM | 328 K | 328 K | 328 K |

hall | 10.8 KM | 257 K | 257 K | 257 K |

mobile | 10.8 KM | 927 K | 927 K | 927 K |

mother-daughter | 10.8 KM | 180 K | 180 K | 180 K |

news | 10.8 KM | 301 K | 301 K | 301 K |

Sequence | PSNR (dB) | |||||
---|---|---|---|---|---|---|

Encoded Video | Encrypted Video | |||||

Y | U | V | Y | U | V | |

coastguard | 34.82 | 42.72 | 44.61 | 14.28 | 31.34 | 40.05 |

containe | 37.06 | 41.36 | 41.22 | 14.62 | 30.10 | 29.02 |

foreman | 36.71 | 40.62 | 41.59 | 12.37 | 28.08 | 28.41 |

hall | 38.12 | 39.71 | 41.46 | 14.27 | 21.32 | 28.05 |

mobile | 33.93 | 35.72 | 35.39 | 12.62 | 19.03 | 19.02 |

mother-daughter | 38.22 | 41.56 | 42.53 | 16.54 | 22.05 | 25.11 |

news | 37.62 | 40.61 | 41.06 | 11.25 | 22.46 | 26.24 |

Video Sequence SSIM Performance Analysis | ||||||
---|---|---|---|---|---|---|

Coastguard | Containe | Foreman | Hall | Mobile | Mother-Daughter | News |

0.31 | 0.53 | 0.36 | 0.42 | 0.10 | 0.48 | 0.29 |

Video Image Type | Video Image 1 | Video Image 2 | ||||
---|---|---|---|---|---|---|

Entropy | PSNR | SSIM | Entropy | PSNR | SSIM | |

original image | 7.2191 | – | 1 | 7.5146 | – | 1 |

Selective video encryption | 7.5944 | 19.983 | 0.29 | 7.2495 | 21.233 | 0.36 |

Introducing 4-D hyperchaotic hybrid encryption | 7.9899 | 9.0644 | 0.0231 | 7.9897 | 9.6759 | 0.0016 |

Existing Schemes | Encrypted Semantic Element | Format Compliant | Bit Increase | Encryption Algorithm |
---|---|---|---|---|

Xu [25] | IPM, MVDs, T1s, signs of the NZ coefficients | yes | no | Chaos |

Abomhara [31] | I frame | no | no | AES |

Shahid [32] | T1s, NZ level | yes | no | AES |

Fei [33] | IPM, MVD, Signs of residual | yes | yes | Chaos |

Sung [34] | Motion vector | yes | yes | RC4 |

Wei [35] | NALUs | yes | yes | RC4 |

Wang [36] | IPM, MVD, Quantization coefficients | yes | yes | Hash and AES |

Ours | IPM, MVDs, Signs of residual, delta QP | yes | yes | Chaos and AES |

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Cheng, S.; Wang, L.; Ao, N.; Han, Q.
A Selective Video Encryption Scheme Based on Coding Characteristics. *Symmetry* **2020**, *12*, 332.
https://doi.org/10.3390/sym12030332

**AMA Style**

Cheng S, Wang L, Ao N, Han Q.
A Selective Video Encryption Scheme Based on Coding Characteristics. *Symmetry*. 2020; 12(3):332.
https://doi.org/10.3390/sym12030332

**Chicago/Turabian Style**

Cheng, Shuli, Liejun Wang, Naixiang Ao, and Qingqing Han.
2020. "A Selective Video Encryption Scheme Based on Coding Characteristics" *Symmetry* 12, no. 3: 332.
https://doi.org/10.3390/sym12030332