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Cited by 5Image and Video Quality AssessmentVideo Coding and Compression TechnologiesChaos-based Image/Signal Encryption

VQProtect: Lightweight Visual Quality Protection for Error-Prone Selectively Encrypted Video Streaming

Open access
Gillani, Syeda Maria, Asghar, Mamoona Naveed, Shifa, Amna, Abdullah, Saima, Kanwal, Nadia, Fleury, Martin·2022·Entropy
DOI 10.3390/e24060755PMC PMC9231263
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Abstract

Mobile multimedia communication requires considerable resources such as bandwidth and efficiency to support Quality-of-Service (QoS) and user Quality-of-Experience (QoE). To increase the available bandwidth, 5G network designers have incorporated Cognitive Radio (CR), which can adjust communication parameters according to the needs of an application. The transmission errors occur in wireless networks, which, without remedial action, will result in degraded video quality. Secure transmission is also a challenge for such channels. Therefore, this paper’s innovative scheme “VQProtect” focuses on the visual quality protection of compressed videos by detecting and correcting channel errors while at the same time maintaining video end-to-end confidentiality so that the content remains unwatchable. For the purpose, a two-round secure process is implemented on selected syntax elements of the compressed H.264/AVC bitstreams. To uphold the visual quality of data affected by channel errors, a computationally efficient Forward Error Correction (FEC) method using Random Linear Block coding (with complexity of O(k(n−1)) is implemented to correct the erroneous data bits, effectively eliminating the need for retransmission. Errors affecting an average of 7–10% of the video data bits were simulated with the Gilbert–Elliot model when experimental results demonstrated that 90% of the resulting channel errors were observed to be recoverable by correctly inferring the values of erroneous bits. The proposed solution’s effectiveness over selectively encrypted and error-prone video has been validated through a range of Video Quality Assessment (VQA) metrics.

AI snapshot

Written from the paper’s full text.

TL;DR

VQProtect combines two-round selective encryption of H.264/AVC CABAC syntax elements with Gilbert–Elliot channel-error simulation and lightweight forward error correction to protect visual quality over error-prone wireless channels. It reports recovery of 90% of simulated channel errors and improved video-quality metrics after FEC, with best visual quality at QP 24.

Key findings

  • The FEC method recovered 90% of resulting channel errors by correctly inferring erroneous bit values; errors were simulated with the Gilbert–Elliot model, described in the abstract as affecting an average of 7–10% of video data bits, while the implementation states MBER varied from 0.07 to 0.1%.
  • Applied FEC has worst-case complexity O(k(n−1)); average processing time with FEC was slightly higher than without FEC, with reported differences of 28, 123, 98, 127, 90, and 122 ms across test videos, and the paper concludes the cost–benefit trade-off favors FEC.
  • PSNR, SSIM, MSE, VQM, histogram, and no-reference blocking/blurring results showed improved quality after FEC; the overall increase in visual quality was best at QP 24, VQM increased with QP, and SSIM was lower at QP 48 even after FEC.
  • In PSNR-based comparison, the proposed scheme outperformed STBMA, JM-FC, and other recently proposed approaches over all test videos.

Methods

  • Three-phase design: (1) compression with two-round selective encryption on CABAC syntax elements—sign bits of MVDs and TC levels—using circular right shift by three bit positions per byte followed by XOR with an n-bit key of at least 128 bits; (2) Gilbert–Elliot Markov-chain channel modeling to introduce burst bit errors; (3) FEC using a (7,4) linear block code with generator and parity-check matrices and syndrome-based error correction.
  • Data: ten test videos from Derf’s collection at CIF (352 × 288, 30 fps), 4CIF (704 × 480, 60 fps), and HD (1280 × 720, 60 fps); encoded with JSVM 9.19 as single-layer H.264/AVC Main/High profile, I+P+B frames, GOP/intra period 16, 4:2:0 chroma subsampling, and QPs 8, 12, 24, 36, and 48.
  • Analysis: video quality assessed with PSNR, SSIM, MSE, VQM, histogram analysis, no-reference blocking and blurring metrics, computational cost/execution time, and comparative PSNR evaluation against other error-correction/concealment methods.

Limitations

  • Stated: the FEC uses a single-bit error handling strategy; future work could use convolution codes for burst errors, tune redundancy by predicting channel loss rate, deploy over an experimental wireless testbed, test complex ciphers such as ChaCha20 and AES, and extend to HEVC, VP9, VVC, and scalable coding.
  • Stated: fixed redundancy overhead is a major compromising factor when using FEC.
  • Evident from the text: the error-rate description is inconsistent—the abstract says errors affected an average of 7–10% of video data bits, while the implementation says MBER varied from 0.07 to 0.1%; the work also relies on software simulation rather than a real CRN/wireless testbed.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.3390/e24060755

Cites

73 of 73 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

4 of 19 cited sources checked · 3 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    For selectively encrypted H.264 video bitstreams, CAVLC is more susceptible to channel error than CABAC.

    “They determined the combined effect of compression and encryption on the video quality and concluded that CAVLC is more susceptible to channel error.”
    • Also stated in: § 3.1. Compression and Privacy Protection · plain
      “As previously discussed in the research of [24], H.264/AVC’s CAVLC is more susceptible to channel errors as compared to CABAC.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [24] Asghar, M.N., Ghanbari, M., Fleury, M., and Reed, M.J. (2012, January 12–13). Analysis of channel error upon selectively encrypted H.264 video. Proceedings of the 2012 4th Computer Science and Electronic Engineering Conference (CEEC), Colchester, UK. source
  • Findingown data

    90% of the resulting channel errors were recoverable by correctly inferring the values of erroneous bits.

    “results demonstrated that 90% of the resulting channel errors were observed to be recoverable by correctly inferring the values of erroneous bits.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The occurrence of bit errors is independent of each other.
    • The authors state this as an assumption: The channel is assumed to be in one of two states only, G or B.
    • The authors state this as an assumption: For inducing a small number of error bits, the G state has a higher probability compared to the probability of error occurrence in the B state.
  • Findingown data

    The visual results show an overall increase in visual quality after applying FEC, particularly at QP 24.

    “The visual results show that an overall increase in visual quality after applying FEC, particularly at QP 24.”
    Quote in the paperSubstantial claim
  • Findingown data

    The video in other modes has a little more amount of blurriness.

    “In contrast, the video in other modes has a little more amount of blurriness.”
    Quote in the paperNot a substantial claim
  • Findingown data

    The average MSE of video recovered with FEC led to the same conclusions as PSNR and SSIM measurement.

    “It is apparent that the average MSE of video recovered with FEC presented in Table 3 and Figure 8 led to the same conclusions as for PSNR and SSIM measurement.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. 14
  • May combine two claims. 15
  • The quote only partly states this claim. 1

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Encryption can be applied as naïve full-content hiding or selective encryption limited to key elements in the compressed bitstream.

    “Encryption can be applied as naïve, for the hiding of full video content, or selective encryption, which limits encryption to key elements in the compressed bitstream [12].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [12] Shifa, 2020, MuLViS: Multi-level encryption based security system for surveillance videos, IEEE Access source

  • May combine two claims.

    Premisecitation

    HEVC increases compression efficiency but has less error-resilient features and is more sensitive to channel bit errors because of more encoded redundant content.

    “The HEVC codec increases the compression efficiency but has less error-resilient features [13] and is more sensitive to channel bit errors because of more encoded redundant content [14].”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [13] Shah, 2019, Effectiveness of crypto-transcoding for H.264/AVC and HEVC video bit-streams, Multimed. Tools Appl. source

      Section 2.4 (p. 6) says HEVC coding refinements can increase the compression ratio by up to 50%. Our copy does not say HEVC has fewer error-resilience features or is more sensitive to channel bit errors because of encoded redundant content; searches for those terms found no supporting passage. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [14] Alfaqheri, 2020, Low delay error resilience algorithm for H. 265| HEVC video transmission, J. Real-Time Image Process. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    SSIM values are not always consistent between two videos of similar resolution.

    “Table 2 depicts that the SSIM values are not always consistent between two videos of similar resolution.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Videos decrypted with FEC code have minimal average VQM values, confirming minimal differences with the original videos.

    “It can be observed from Table 3 and Figure 9 that videos decrypted with FEC code have minimal values of average VQM, confirming that there are minimal differences with the original videos.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingnone given

    The calculated MBER was varied from 0.07 to 0.1% and was computed over the total number of bits transmitted per sequence.

    “In our implementation, the calculated MBER was varied from 0.07 to 0.1%, and it was computed over the total number of bits transmitted per sequence.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The occurrence of bit errors is independent of each other.
    • The authors state this as an assumption: The channel is assumed to be in one of two states only, G or B.
    • The authors state this as an assumption: For inducing a small number of error bits, the G state has a higher probability compared to the probability of error occurrence in the B state.

  • The quote only partly states this claim.

    Findingown data

    The selectively encrypted test videos with channel errors induced by the GE channel model showed significant visual quality degradation after decoding without FEC.

    “Figure 5 (d1, d2, d3) shows the decoded form of videos given in Figure 5 (c1, c2, c3), respectively, where a significant degradation in the visual quality can be observed.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The H.264/AVC standard remains a widely deployed codec in real-time video streaming applications.

    “For example, the H.264/Advanced Video Coding (AVC) standard [2] remains a widely deployed codec in real-time video streaming applications.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [2] Marpe, 2006, The H.264/MPEG4 advanced video coding standard and its applications, IEEE Commun. Mag. source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    FEC is especially used in real-time multimedia applications when real-time data are needed and when the delay caused by retransmission requests is not tolerable.

    “FEC is especially used in real-time multimedia applications when real-time data are needed and when the delay caused by retransmission requests is not tolerable.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [8] Hu, 2009, An error resilient video coding and transmission solution over error-prone channels, J. Vis. Commun. Image Represent. source

  • May combine two claims.

    Interpretationnone given

    Selected syntax elements output by the CABAC entropy coder of H.264/AVC were encrypted by a two-round secure process that permits real-time operation by low-complexity processing devices.

    “For securing the videos, selected syntax elements output by the CABAC entropy coder of H.264/AVC were encrypted by a two-round secure process, which permits real-time operation by low-complexity processing devices, such as those now being deployed within sensor networks.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A PSNR between 20 and 25 dB is considered acceptable for wireless transmission quality loss.

    “Generally, a PSNR that is between 20 and 25 dB is considered to be acceptable for wireless transmission quality loss [66].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [66] Thomos, 2005, Optimized transmission of JPEG2000 streams over wireless channels, IEEE Trans. Image Process. source

  • May combine two claims.

    Interpretationreasoning

    Selective encryption on MVDs and TCs keeps the video format compliant and playable and does not escalate bit rates.

    “The selective encryption on MVDs and TCs keeps the video format compliant (playable) and without escalating bit rates.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    The proposed scheme can protect video content both against unauthorized access and transmission errors while maintaining video quality similar to the original video.

    “The proposed scheme can help protect video content both against unauthorized access and transmission errors while maintaining the video quality similar to that of the original video.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    The proposed protection scheme for the H.264-CABAC entropy coder can be applied to HEVC compression with a few comparatively minor modifications.

    “Thus, this paper devised a protection scheme for the H.264-CABAC entropy coder, which can be applied to HEVC compression, with a few comparatively minor modifications.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Unlike ARQ, FEC restores errors without requesting retransmission, so when transmission delay matters, FEC may be quicker and more suitable.

    “Unlike Automatic Repeat Request (ARQ), when an error is detected within the transmitted data, FEC restores it without requesting re-transmission. Thus, when transmission delay matters, FEC may be a quicker and more suitable option to choose [9].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [9] Song, J., Yang, Z., and Wang, J. (2015). Channel Coding for DTTB System, Chapter Digital Terrestrial Television Broadcasting: Technology and System; Wiley. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The Gilbert-Elliot model is extensively used to represent bursty error patterns in transmission channels.

    “The Gilbert–Elliot (GE) [26,27] is extensively used to represent ‘bursty’ error patterns in transmission channels, allowing analysis of the transmission efficiency, such as how many errors an error-recovery scheme detects and corrects induced in its channel.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [26] Bildea, A., Alphand, O., Rousseau, F., and Duda, A. (September, January 30). Link quality estimation with the Gilbert-Elliot model for wireless sensor networks. Proceedings of the 2015 IEEE 26th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), Hong Kong, China. source
    • cites [27] Elliott, 1963, Estimates of error rates for codes on burst-noise channels, Bell Syst. Tech. J. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisereasoning

    The syndrome is purely a function of the error patterns and not the actual or transmitted codewords.

    “It is also noticeable that the syndrome is purely a function of the error patterns and not the actual or transmitted codewords.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    VQProtect protects the visual quality of compressed videos by detecting and correcting channel errors while maintaining end-to-end confidentiality so that the content remains unwatchable.

    “Therefore, this paper’s innovative scheme “VQProtect” focuses on the visual quality protection of compressed videos by detecting and correcting channel errors while at the same time maintaining video end-to-end confidentiality so that the content remains unwatchable.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    FEC is a channel coding technique that adds redundancy to transmitted data to achieve error control.

    “An FEC is a channel coding technique that adds redundancy to transmitted data to achieve error control [28] by which the transmitter sends data along with the redundant information and the receiver distinguishes and identifies only the original data and requires the redundant bits only in the case of some bit error or data loss.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [28] EzZazi, I., Arioua, M., El Oualkadi, A., and el Assari, Y. (2017, January 19–20). Joint FEC/CRC coding scheme for energy constrained IoT devices. Proceedings of the International Conference on Future Networks and Distributed Systems, Cambridge, UK. source

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    Using FEC to recover bit errors during transmission eliminates the need for retransmitting data, making broadcasting, video streaming, and real-time applications more efficient.

    “In this paper, FEC is used to recover the bit errors that occurred during transmission to eliminate the need for retransmitting data, which, if retransmission is not needed, makes broadcasting, video streaming, and real-time applications more efficient.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given

    The Gilbert-Elliot model is computationally expensive when considering error events in both states.

    “The GE model is computationally expensive when considering error events in both states.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    The proposed scheme preserves the video quality of the original video intact and utilizes a minimum of bandwidth.

    “This paper proposes a joint protection and error recovery mechanism for compressed videos against transmission losses and unauthorized access to the content while preserving the video quality intact of the original video and utilizing a minimum of bandwidth.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    The implemented FEC code can detect and correct both single-bit and multibit errors to achieve sufficient QoE.

    “The FEC code can be used to detect and correct both single bit and multibit errors to achieve sufficient QoE.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationnone given

    The error method proposed in this paper is a bit-inversion technique that detects errors in encoded bitstreams and simply inverts bit errors, resulting in improved reduced computational cost.

    “However, the error method proposed in this paper is a bit-inversion technique, which, by detecting the errors in encoded bitstreams and simply inverting bit errors, results in an improved, reduced computational cost.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    The implemented FEC scheme is relatively simple and does not noticeably increase computational complexity because it does not involve complex mathematical operations.

    “The computational cost analysis and worst-case complexity of the implemented FEC scheme is a relatively simple method that does not noticeably increase computational complexity because it does not involve complex mathematical operations.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    A computationally efficient FEC method using Random Linear Block coding with complexity O(k(n−1)) corrects erroneous data bits, eliminating the need for retransmission.

    “To uphold the visual quality of data affected by channel errors, a computationally efficient Forward Error Correction (FEC) method using Random Linear Block coding (with complexity of O(k(n−1)) is implemented to correct the erroneous data bits, effectively eliminating the need for retransmission.”
    Quote in the paperSubstantial claim
25 of 25

  • The paper relies on this without support.

    A simple XOR cipher can be easily compromised.

    “For computationally efficient encryption rounds, a simple XOR cipher is used, which, however, can be easily compromised.”

  • The authors state this as an assumption.

    The occurrence of bit errors is independent of each other.

    “It should be noticed that the GE model is used to introduce bit errors in the selectively encrypted bitstream, assuming that the occurrence of bit errors is independent of each other.”

  • The authors state this as an assumption.

    The channel is assumed to be in one of two states only, G or B.

    “As in this work, the channel is assumed to be in one of the two states only, i.e., G or B, so the mean sojourn time of state G and state B denoted by TG and TB, respectively, can be estimated through (3) and (4) as:”

  • The authors state this as an assumption.

    For inducing a small number of error bits, the G state has a higher probability compared to the probability of error occurrence in the B state.

    “For inducing a small number of error bits, we assume P(G)>P(B) that the G state has a higher probability compared to the probability of error occurrence in the B state.”

  • The paper relies on this without support.

    The human visual system is more sensitive to luminance than to chrominance.

    “as the human visual system is more sensitive to luminance than chrominance (recorded in the U and V components).”

  • The authors state this as an assumption.

    The Gilbert–Elliot model adequately models the error-prone communication channel used in the experiments.

    “channel error simulation is performed using the Gilbert–Elliot model.”
6 of 6

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Reported channel-error rates differ by a factor of 100

    Major

    The abstract says errors affected 7-10% of video data bits, whereas the channel-model description says the mean bit-error rate varied from 0.07 to 0.1%. These are different ranges, not alternate ways of expressing the same percentages.

  • Six processing-time comparisons have only five without-FEC inputs

    Minor

    The processing-time statement names six videos and supplies six with-FEC times and six differences, but lists only five without-FEC times. The stated 122 ms difference for the sixth video therefore has no corresponding listed without-FEC time.

  • Generator and parity-check matrices are incompatible

    Minor

    The fourth generator-matrix row specifies parity bits 0,1,0, but the parity-check matrix's fourth column is 0,1,1. Consequently, the error-free word generated from dataword 0001 has a nonzero syndrome under the stated parity-check matrix.

  • Bad-state error probability is specified as both 1 and 0.8

    Minor

    The channel-model description first makes an error certain in the bad state, then states that the implemented probability of an error in that state was 0.8.

  • Mobile-video processing-time difference is miscalculated

    Minor

    For Mobile, the listed times with and without FEC are 620 ms and 491 ms, a difference of 129 ms rather than the reported 123 ms.

    Reported 123 · recomputed 129

  • Stated generator matrix cannot uniquely correct every single-bit error

    Minor

    The generator matrix makes both 0000000 and 0001010 valid codewords, only two bits apart. A received word one bit away from each cannot have a unique single-bit correction, contrary to the claimed one-to-one correspondence.

  • Claimed ordering of state-error probabilities reverses the stated values

    Minor

    The text assumes P(G)>P(B), but its stated values are P(G)=0 and P(B)=1.

7 of 7

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. Nunome, 2020, The Effect of MMT ALFEC on QoE of Error-Concealed Video Streaming, ITE Trans. Media Technol. Appl., 8, 186

Cited by

Still being checked.

Related

Authors
Gillani, S. M., Asghar, M. N., Shifa, A., Abdullah, S., Kanwal, N., & Fleury, M.
Affiliations
  • Islamia University of Bahawalpur (PK)
  • Lahore College for Women University (PK)
  • University of Suffolk (GB)
Corresponding author
Asghar, Mamoona Naveed
ORCID
Venue
Entropy
Publisher
MDPI AG
Published
2022-05-26
Volume
24
Issue
6
Pages
755
ISSN
1099-4300 (ISSN-L)
DOI
10.3390/e24060755
PMC
PMC9231263
OpenAlex
W4281729474
Semantic Scholar
c2d4d0b9d3b8b9a27dc49803f154bca0109df86b
Cited by
5
References
73
Citations by year
2026: 1 · 2025: 1 · 2024: 1 · 2023: 2
FWCI
0.32
Type
journal article
Language
en
Open access
Licence
Locations
  • Entropy (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Keele Research Repository (Keele University) (submittedVersion, cc-by)
  • PubMed Central (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Topics
  • Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Image and Video Quality Assessment
  • Physical Sciences › Computer Science › Signal Processing › Video Coding and Compression Technologies
  • Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Chaos-based Image/Signal Encryption
Keywords
selective encryption, video streaming, forward error correction, cognitive radio, 5G, video quality assessment

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