The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Jari Korhonen - One of the best experts on this subject based on the ideXlab platform.

  • no reference Video quality assessment using codec analysis
    IEEE Transactions on Circuits and Systems for Video Technology, 2015
    Co-Authors: Jacob Sogaard, Soren Forchhammer, Jari Korhonen
    Abstract:

    A no-reference (NR) Video quality assessment (VQA) method is presented for Videos distorted by H.264/Advanced Video Coding (AVC) and MPEG-2. The assessment is performed without access to the bitstream. Instead, we analyze and estimate coefficients based on decoded pixels. The approach involves distinguishing between the two types of Videos, estimating the level of quantization used in the I-frames, and exploiting this information to assess the Video quality. To do this for H.264/AVC, the distribution of the discrete cosine transform-coefficients after intra-prediction and deblocking are modeled. To obtain VQA features for H.264/AVC, we propose a novel estimation method of the quantization in H.264/AVC Videos without bitstream access, which can also be used for peak signal-to-noise ratio estimation. The results from the MPEG-2 and H.264/AVC analysis are mapped to a perceptual measure of Video quality by support vector regression. For validation purposes, the proposed method was tested on two databases. In both cases, a good performance compared with state of the art full, reduced, and NR VQA algorithms was achieved.

Shiguo Lian - One of the best experts on this subject based on the ideXlab platform.

  • efficient Video encryption scheme based on Advanced Video Coding
    Multimedia Tools and Applications, 2008
    Co-Authors: Shiguo Lian, Jinsheng Sun, Guangjie Liu, Zhiquan Wang
    Abstract:

    A Video encryption scheme combining with Advanced Video Coding (AVC) is presented and analyzed in this paper, which is different from the ones used in MPEG1/2 Video encryption. In the proposed scheme, the intra-prediction mode and motion vector difference are encrypted with the length-kept encryption algorithm (LKE) in order to keep the format compliance, and the residue data of the macroblocks are encrypted with the residue data encryption algorithm (RDE) in order to keep low cost. Additionally, a key distribution scheme is proposed to keep the robustness to transmission errors, which assigns sub-keys to different frames or slices independently. The encryption scheme's security, time efficiency and error robustness are analyzed in detail. Experimental results show that the encryption scheme keeps file format unchanged, is secure against replacement attacks, is efficient in computing, and is robust to some transmission errors. These properties make it a suitable choice for real-time applications, such as secure IPTV, secure Videoconference or mobile/wireless multimedia, etc.

  • commutative encryption and watermarking in Video compression
    IEEE Transactions on Circuits and Systems for Video Technology, 2007
    Co-Authors: Shiguo Lian, Zhongxuan Liu, Zhen Ren, Haila Wang
    Abstract:

    A scheme is proposed to implement commutative Video encryption and watermarking during Advanced Video Coding process. In H.264/AVC compression, the intra-prediction mode, motion vector difference and discrete cosine transform (DCT) coefficients' signs are encrypted, while DCT coefficients' amplitudes are watermarked adaptively. To avoid that the watermarking operation affects the decryption operation, a traditional watermarking algorithm is modified. The encryption and watermarking operations are commutative. Thus, the watermark can be extracted from the encrypted Videos, and the encrypted Videos can be re-watermarked. This scheme embeds the watermark without exposing Video content's confidentiality, and provides a solution for signal processing in encrypted domain. Additionally, it increases the operation efficiency, since the encrypted Video can be watermarked without decryption. These properties make the scheme a good choice for secure media transmission or distribution

  • secure Advanced Video Coding based on selective encryption algorithms
    IEEE Transactions on Consumer Electronics, 2006
    Co-Authors: Shiguo Lian, Zhongxuan Liu, Zhen Ren, Haila Wang
    Abstract:

    Advanced Video Coding is recently announced and widely used, although the according protection means have not been developed thoroughly. In this paper, a secure AVC Coding scheme is presented based on some partial encryption algorithms. During AVC enCoding, such sensitive data as intra-prediction mode, residue data and motion vector are encrypted partially. Among them, the infra-prediction mode is encrypted based on exp-Golomb entropy Coding, the intra-macroblocks' DCs are encrypted based on context-based adaptive variable length Coding (CAVLC), and infra-macroblocks' ACs and the inter-macroblocks' MVDs are sign-encrypted with a stream cipher followed with variable-length Coding. This encryption scheme is secure in perception, keeps format compliance, and obtains high time efficiency though reducing the encrypted data volumes. These properties make it practical to incorporate encryption/decryption process into compression/decompression process, and thus suitable for secure Video transmission or sharing.

  • selective Video encryption based on Advanced Video Coding
    Lecture Notes in Computer Science, 2005
    Co-Authors: Shiguo Lian, Zhongxuan Liu, Zhen Ren, Zhiquan Wang
    Abstract:

    Advanced Video Coding is recently announced and widely used, although the according protection means have not been developed thoroughly. In this paper, a selective encryption scheme is constructed on Advanced Video Coding. During AVC enCoding, such sensitive data as intra-prediction mode, residue data, inter-prediction mode and motion vector are partially encrypted. This encryption scheme keeps secure against brute-force attack, replacement attack or known-plaintext attack, combines encryption process with compression process with low cost, and keeps the file format unchanged with some direct operations (such as displaying, time seeking, copying, cutting, etc.) supported. These properties make it suitable for secure Video transmission.

Gary J Sullivan - One of the best experts on this subject based on the ideXlab platform.

  • High efficiency Video Coding: the next frontier in Video compression [Standards in a Nutshell]
    IEEE Signal Processing Magazine, 2013
    Co-Authors: Jensrainer Ohm, Gary J Sullivan
    Abstract:

    High Efficiency Video Coding (HEVC) is a new Video compression standard developed jointly by ITU-T Video Coding Experts Group (VCEG) and ISO/IEC Moving Pictures Expert Group (MPEG) through their Joint Collaborative Team on Video Coding (JCT-VC). The first version of HEVC will be finalized by the JCT-VC in January 2013. The HEVC project was launched to achieve major savings-e.g., reduction by about half for 1,280 × 720 high-definition (HD) and higher-resolution progressives can Video-for equivalent visual quality relative to the bit rate needed by the widely used H.264/ MPEG-4 Advanced Video Coding (AVC) standard. For high resolution Video where such additional compression is most urgently required, implementations of the current draft standard are already meeting or exceeding the targeted goal. We review the architecture and building blocks of HEVC, which were carefully selected with regard to compression capability versus complexity and to enable parallelism for the signal processing operations. Given the benefits that HEVC provides, it is likely to become the new primary reference for Video compression.

  • comparison of the Coding efficiency of Video Coding standards including high efficiency Video Coding hevc
    IEEE Transactions on Circuits and Systems for Video Technology, 2012
    Co-Authors: Jensrainer Ohm, Heiko Schwarz, Gary J Sullivan, Thiow Keng Tan, Thomas Wiegand
    Abstract:

    The compression capability of several generations of Video Coding standards is compared by means of peak signal-to-noise ratio (PSNR) and subjective testing results. A unified approach is applied to the analysis of designs, including H.262/MPEG-2 Video, H.263, MPEG-4 Visual, H.264/MPEG-4 Advanced Video Coding (AVC), and High Efficiency Video Coding (HEVC). The results of subjective tests for WVGA and HD sequences indicate that HEVC encoders can achieve equivalent subjective reproduction quality as encoders that conform to H.264/MPEG-4 AVC when using approximately 50% less bit rate on average. The HEVC design is shown to be especially effective for low bit rates, high-resolution Video content, and low-delay communication applications. The measured subjective improvement somewhat exceeds the improvement measured by the PSNR metric.

  • the h 264 mpeg4 Advanced Video Coding standard and its applications
    IEEE Communications Magazine, 2006
    Co-Authors: Detlev Marpe, Thomas Wiegand, Gary J Sullivan
    Abstract:

    H.264/MPEG4-AVC is the latest Video Coding standard of the ITU-T Video Coding experts group (VCEG) and the ISO/IEC moving picture experts group (MPEG). H.264/MPEG4-AVC has recently become the most widely accepted Video Coding standard since the deployment of MPEG2 at the dawn of digital television, and it may soon overtake MPEG2 in common use. It covers all common Video applications ranging from mobile services and Videoconferencing to IPTV, HDTV, and HD Video storage. This article discusses the technology behind the new H.264/MPEG4-AVC standard, focusing on the main distinct features of its core Coding technology and its first set of extensions, known as the fidelity range extensions (FRExt). In addition, this article also discusses the current status of adoption and deployment of the new standard in various application areas

  • the h 264 avc Advanced Video Coding standard overview and introduction to the fidelity range extensions
    Optical Science and Technology the SPIE 49th Annual Meeting, 2004
    Co-Authors: Gary J Sullivan, Pankaj N Topiwala, Ajay Luthra
    Abstract:

    H.264/MPEG-4 AVC is the latest international Video Coding standard. It was jointly developed by the Video Coding Experts Group (VCEG) of the ITU-T and the Moving Picture Experts Group (MPEG) of ISO/IEC. It uses state-of-the-art Coding tools and provides enhanced Coding efficiency for a wide range of applications, including Video telephony, Video conferencing, TV, storage (DVD and/or hard disk based, especially high-definition DVD), streaming Video, digital Video authoring, digital cinema, and many others. The work on a new set of extensions to this standard has recently been completed. These extensions, known as the Fidelity Range Extensions (FRExt), provide a number of enhanced capabilities relative to the base specification as approved in the Spring of 2003. In this paper, an overview of this standard is provided, including the highlights of the capabilities of the new FRExt features. Some comparisons with the existing MPEG-2 and MPEG-4 Part 2 standards are also provided.

  • rate constrained coder control and comparison of Video Coding standards
    IEEE Transactions on Circuits and Systems for Video Technology, 2003
    Co-Authors: Thomas Wiegand, Anthony Joch, Faouzi Kossentini, Heiko Schwarz, Gary J Sullivan
    Abstract:

    A unified approach to the coder control of Video Coding standards such as MPEG-2, H.263, MPEG-4, and the draft Video Coding standard H.264/AVC (Advanced Video Coding) is presented. The performance of the various standards is compared by means of PSNR and subjective testing results. The results indicate that H.264/AVC compliant encoders typically achieve essentially the same reproduction quality as encoders that are compliant with the previous standards while typically requiring 60% or less of the bit rate.

Soren Forchhammer - One of the best experts on this subject based on the ideXlab platform.

  • no reference Video quality assessment using codec analysis
    IEEE Transactions on Circuits and Systems for Video Technology, 2015
    Co-Authors: Jacob Sogaard, Soren Forchhammer, Jari Korhonen
    Abstract:

    A no-reference (NR) Video quality assessment (VQA) method is presented for Videos distorted by H.264/Advanced Video Coding (AVC) and MPEG-2. The assessment is performed without access to the bitstream. Instead, we analyze and estimate coefficients based on decoded pixels. The approach involves distinguishing between the two types of Videos, estimating the level of quantization used in the I-frames, and exploiting this information to assess the Video quality. To do this for H.264/AVC, the distribution of the discrete cosine transform-coefficients after intra-prediction and deblocking are modeled. To obtain VQA features for H.264/AVC, we propose a novel estimation method of the quantization in H.264/AVC Videos without bitstream access, which can also be used for peak signal-to-noise ratio estimation. The results from the MPEG-2 and H.264/AVC analysis are mapped to a perceptual measure of Video quality by support vector regression. For validation purposes, the proposed method was tested on two databases. In both cases, a good performance compared with state of the art full, reduced, and NR VQA algorithms was achieved.

  • fast compressed domain motion detection in h 264 Video streams for Video surveillance applications
    Advanced Video and Signal Based Surveillance, 2009
    Co-Authors: Krzysztof Szczerba, Soren Forchhammer, Jesper Stottrupandersen, Peder Tanderup Eybye
    Abstract:

    This paper presents a novel approach to fast motion detection in H.264/MPEG-4 Advanced Video Coding (AVC) compressed Video streams for IP Video surveillance systems. The goal is to develop algorithms which may be useful in a real-life industrial perspective by facilitating the processing of large numbers of Video streams on a single server. The focus of the work is on using the information in coded Video streams to reduce the computational complexity and memory requirements, which translates into reduced hardware requirements and costs. The devised algorithm detects and segments activity based on motion vectors embedded in the Video stream without requiring a full deCoding and reconstruction of Video frames. To improve the robustness to noise, a confidence measure based on temporal and spatial clues is introduced to increase the probability of correct detection. The algorithm was tested on indoor surveillance H.264 sequences.

Jacob Sogaard - One of the best experts on this subject based on the ideXlab platform.

  • no reference Video quality assessment using codec analysis
    IEEE Transactions on Circuits and Systems for Video Technology, 2015
    Co-Authors: Jacob Sogaard, Soren Forchhammer, Jari Korhonen
    Abstract:

    A no-reference (NR) Video quality assessment (VQA) method is presented for Videos distorted by H.264/Advanced Video Coding (AVC) and MPEG-2. The assessment is performed without access to the bitstream. Instead, we analyze and estimate coefficients based on decoded pixels. The approach involves distinguishing between the two types of Videos, estimating the level of quantization used in the I-frames, and exploiting this information to assess the Video quality. To do this for H.264/AVC, the distribution of the discrete cosine transform-coefficients after intra-prediction and deblocking are modeled. To obtain VQA features for H.264/AVC, we propose a novel estimation method of the quantization in H.264/AVC Videos without bitstream access, which can also be used for peak signal-to-noise ratio estimation. The results from the MPEG-2 and H.264/AVC analysis are mapped to a perceptual measure of Video quality by support vector regression. For validation purposes, the proposed method was tested on two databases. In both cases, a good performance compared with state of the art full, reduced, and NR VQA algorithms was achieved.