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Touradj Ebrahimi - One of the best experts on this subject based on the ideXlab platform.

  • Overview and evaluation of the JPEG XT HDR image Compression Standard
    Journal of Real-Time Image Processing, 2019
    Co-Authors: Alessandro Artusi, Rafał K. Mantiuk, Massimiliano Agostinelli, Arkady Ten, Thomas Richter, Philippe Hanhart, Pavel Korshunov, Touradj Ebrahimi
    Abstract:

    Standards play an important role in providing a common set of specifications and allowing inter-operability between devices and systems. Until recently, no Standard for high-dynamic-range (HDR) image coding had been adopted by the market, and HDR imaging relies on proprietary and vendor-specific formats which are unsuitable for storage or exchange of such images. To resolve this situation, the JPEG Committee is developing a new coding Standard called JPEG XT that is backward compatible to the popular JPEG Compression, allowing it to be implemented using Standard 8-bit JPEG coding hardware or software. In this paper, we present design principles and technical details of JPEG XT. It is based on a two-layer design, a base layer containing a low-dynamic-range image accessible to legacy implementations, and an extension layer providing the full dynamic range. The paper introduces three of currently defined profiles in JPEG XT, each constraining the common decoder architecture to a subset of allowable configurations. We assess the coding efficiency of each profile extensively through subjective assessments, using 24 naïve subjects to evaluate 20 images, and objective evaluations, using 106 images with five different tone-mapping operators and at 100 different bit rates. The objective results (based on benchmarking with subjective scores) demonstrate that JPEG XT can encode HDR images at bit rates varying from 1.1 to 1.9 bit/pixel for estimated mean opinion score (MOS) values above 4.5 out of 5, which is considered as fully transparent in many applications. This corresponds to 23-times bitstream reduction compared to lossless OpenEXR PIZ Compression.

  • overview and evaluation of the jpeg xt hdr image Compression Standard
    Journal of Real-time Image Processing, 2019
    Co-Authors: Alessandro Artusi, Rafał K. Mantiuk, Massimiliano Agostinelli, Arkady Ten, Thomas Richter, Philippe Hanhart, Pavel Korshunov, Touradj Ebrahimi
    Abstract:

    Standards play an important role in providing a common set of specifications and allowing inter-operability between devices and systems. Until recently, no Standard for High Dynamic Range (HDR) image coding had been adopted by the market, and HDR imaging relies on proprietary and vendor specific formats which are unsuitable for storage or exchange of such images. To resolve this situation, the JPEG Committee is developing a new coding Standard called JPEG XT that is backwards compatible to the popular JPEG Compression, allowing it to be implemented using Standard 8-bit JPEG coding hardware or software. In this paper, we present design principles and technical details of JPEG XT. It is based on a two-layers design, a base layer containing a Low Dynamic Range (LDR) image accessible to legacy implementations, and an extension layer providing the full dynamic range. The paper introduces three of currently defined profiles in JPEG XT, each constraining the common decoder architecture to a subset of allowable configurations. We assess the coding efficiency of each profile extensively through subjective assessments, using 24 naive subjects to evaluate 20 images, and objective evaluations, using 106 images with five different tone-mapping operators and at 100 different bit rates. The objective results (based on benchmarking with subjective scores) demonstrate that JPEG XT can encode HDR images at bit rates varying from 1.1 to 1.9 bit/pixel for estimated mean opinion score (MOS) values above 4.5 out of 5, which is considered as fully transparent in many applications. This corresponds to 23-times bitstream reduction compared to lossless OpenEXR PIZ Compression.

  • jpeg xt a Compression Standard for hdr and wcg images Standards in a nutshell
    IEEE Signal Processing Magazine, 2016
    Co-Authors: Alessandro Artusi, Rafał K. Mantiuk, Thomas Richter, Philippe Hanhart, Pavel Korshunov, Touradj Ebrahimi, Massimiliano Agostinelli
    Abstract:

    High bit depth data acquisition and manipulation have been largely studied at the academic level over the last 15 years and are rapidly attracting interest at the industrial level. An example of the increasing interest for high-dynamic range (HDR) imaging is the use of 32-bit floating point data for video and image acquisition and manipulation that allows a variety of visual effects that closely mimic the real-world visual experience of the end user [1] (see Figure 1). At the industrial level, we are witnessing increasing traction toward supporting HDR and wide color gamut (WCG). WCG leverages HDR for each color channel to display a wider range of colors. Consumer cameras are currently available with a 14- or 16-bit analog-to-digital converter. Rendering devices are also appearing with the capability to display HDR images and video with a peak brightness of up to 4,000 nits and to support WCG (ITU-R Rec. BT.2020 [2]) rather than the historical ITU-R Rec. BT.709 [3]. This trend calls for a widely accepted Standard for higher bit depth support that can be seamlessly integrated into existing products and applications.

  • performance evaluation of the emerging jpeg xt image Compression Standard
    Multimedia Signal Processing, 2014
    Co-Authors: Antonio M G Pinheiro, Pavel Korshunov, Karel Fliegel, Lukas Krasula, Marco V Bernardo, Manuela Pereira, Touradj Ebrahimi
    Abstract:

    The upcoming JPEG XT is under development for High Dynamic Range (HDR) image Compression. This Standard encodes a Low Dynamic Range (LDR) version of the HDR image generated by a Tone-Mapping Operator (TMO) using the conventional JPEG coding as a base layer and encodes the extra HDR information in a residual layer. This paper studies the performance of the three profiles of JPEG XT (referred to as profiles A, B and C) using a test set of six HDR images. Four TMO techniques were used for the base layer image generation to assess the influence of the TMOs on the performance of JPEG XT profiles. Then, the HDR images were coded with different quality levels for the base layer and for the residual layer. The performance of each profile was evaluated using Signal to Noise Ratio (SNR), Feature SIMilarity Index (FSIM), Root Mean Square Error (RMSE), and CIEDE2000 color difference objective metrics. The evaluation results demonstrate that profiles A and B lead to similar saturation of quality at the higher bit rates, while profile C exhibits no saturation. Profiles B and C appear to be more dependent on TMOs used for the base layer compared to profile A.

  • subjective quality evaluation of the upcoming hevc video Compression Standard
    Proceedings of SPIE, 2012
    Co-Authors: Philippe Hanhart, Martin Rerabek, Francesca De Simone, Touradj Ebrahimi
    Abstract:

    High Efficiency Video Coding (HEVC) is the latest attempt by ISO/MPEG and ITU-T/VCEG to define the next generation Compression Standard beyond H.264/MPEG-4 Part 10 AVC. One of the major goals of HEVC is to provide efficient Compression for resolutions beyond HDTV. However, the subjective evaluations that led to the selection of technologies were bound to HDTV resolution. Moreover, performance evaluation metrics to report efficiency results of this Standard are mainly based on PSNR, especially for resolutions beyond HDTV. This paper provides subjective evaluation results to assess the performance of the current HEVC codec for resolutions beyond HDTV.

C M Brislawn - One of the best experts on this subject based on the ideXlab platform.

  • FBI Compression Standard for digitized fingerprint images
    Applications of Digital Image Processing XIX, 1996
    Co-Authors: C M Brislawn, J N Bradley, Remigius J. Onyshczak, Thomas Hopper
    Abstract:

    The FBI has formulated national Standards for digitization and Compression of gray-scale fingerprint images. The Compression algorithm for the digitized images is based on adaptive uniform scalar quantization of a discrete wavelet transform subband decomposition, a technique referred to as the wavelet/scalar quantization method. The algorithm produces archival-quality images at Compression ratios of around 15 to 1 and will allow the current database of paper fingerprint cards to be replaced by digital imagery. A compliance testing program is also being implemented to ensure high Standards of image quality and interchangeability of data between different implementations. We will review the current status of the FBI Standard, including the compliance testing process and the details of the first-generation encoder.

  • The FBI Compression Standard for digitized fingerprint images
    1996
    Co-Authors: C M Brislawn, J N Bradley, Remigius J. Onyshczak, Thomas Hopper
    Abstract:

    The FBI has formulated national Standards for digitization and Compression of gray-scale fingerprint images. The Compression algorithm for the digitized images is based on adaptive uniform scalar quantization of a discrete wavelet transform subband decomposition, a technique referred to as the wavelet/scalar quantization method. The algorithm produces archival-quality images at Compression ratios of around 15 to 1 and will allow the current database of paper fingerprint cards to be replaced by digital imagery. A compliance testing program is also being implemented to ensure high Standards of image quality and interchangeability of data between different implementations. We will review the current status of the FBI Standard, including the compliance testing process and the details of the first-generation encoder.

  • Wavelet/scalar quantization Compression Standard for fingerprint images
    1996
    Co-Authors: C M Brislawn
    Abstract:

    US Federal Bureau of Investigation (FBI) has recently formulated a national Standard for digitization and Compression of gray-scale fingerprint images. Fingerprints are scanned at a spatial resolution of 500 dots per inch, with 8 bits of gray-scale resolution. The Compression algorithm for the resulting digital images is based on adaptive uniform scalar quantization of a discrete wavelet transform subband decomposition (wavelet/scalar quantization method). The FBI Standard produces archival-quality images at Compression ratios of around 15 to 1 and will allow the current database of paper fingerprint cards to be replaced by digital imagery. The Compression Standard specifies a class of potential encoders and a universal decoder with sufficient generality to reconstruct compressed images produced by any compliant encoder, allowing flexibility for future improvements in encoder technology. A compliance testing program is also being implemented to ensure high Standards of image quality and interchangeability of data between different implementations.

  • the wavelet scalar quantization Compression Standard for digital fingerprint images
    International Symposium on Circuits and Systems, 1994
    Co-Authors: J N Bradley, C M Brislawn
    Abstract:

    A new digital image Compression Standard has been adopted by the US Federal Bureau of Investigation for use on digitized gray-scale fingerprint images. The algorithm is based on adaptive uniform scalar quantization of a discrete wavelet transform image decomposition and is referred to as the wavelet/scalar quantization Standard. The Standard produces archival quality images at Compression ratios of around 20:1 and will allow the FBI to replace their current database of paper fingerprint cards with digital imagery. >

  • ISCAS - The wavelet/scalar quantization Compression Standard for digital fingerprint images
    Proceedings of IEEE International Symposium on Circuits and Systems - ISCAS '94, 1
    Co-Authors: J N Bradley, C M Brislawn
    Abstract:

    A new digital image Compression Standard has been adopted by the US Federal Bureau of Investigation for use on digitized gray-scale fingerprint images. The algorithm is based on adaptive uniform scalar quantization of a discrete wavelet transform image decomposition and is referred to as the wavelet/scalar quantization Standard. The Standard produces archival quality images at Compression ratios of around 20:1 and will allow the FBI to replace their current database of paper fingerprint cards with digital imagery. >

Martin Vaculik - One of the best experts on this subject based on the ideXlab platform.

  • Impact of GoP on the video quality of VP9 Compression Standard for full HD resolution
    Advances in Electrical and Electronic Engineering, 2016
    Co-Authors: Miroslav Uhrina, Juraj Bienik, Martin Vaculik
    Abstract:

    In the last years, the interest on multimedia services has significantly increased. This leads to requirements for quality assessment, especially in video domain. Compression together with the transmission link imperfection are two main factors that influence the quality. This paper deals with the assessment of the Group of Pictures (GoP) impact on the video quality of VP9 Compression Standard. The evaluation was done using selected objective and subjective methods for two types of Full HD sequences depending on content. These results are part of a new model that is still being created and will be used for predicting the video quality in networks based on IP.

  • Procedure for mapping of objective video quality metrics to subjective MOS scale of VP 9 Compression Standard for Full HD resolution
    2016 International Conference on Information and Digital Technologies (IDT), 2016
    Co-Authors: Miroslav Uhrina, Juraj Bienik, Martin Vaculik
    Abstract:

    In the last years the interest on multimedia services has rapidly increased which leads to requirements of quality assessment, especially in video domain. Compression together with transmission link imperfection are two main factors that influence the quality. This paper deals with the video quality assessment of the impact of VP9 Compression Standard using both objective and subjective methods for Full HD resolution. Afterwards the correlation between all objective and subjective methods is calculated as well as the mapping procedure of selected objective method into the subjective MOS scale is done.

  • SPECTS - Subjective video quality assessment of VP9 Compression Standard for full HD resolution
    2016 International Symposium on Performance Evaluation of Computer and Telecommunication Systems (SPECTS), 2016
    Co-Authors: Miroslav Uhrina, Martin Vaculik, Juraj Bienik, Miroslav Voznak
    Abstract:

    Interest in new multimedia services has rapidly increased over last years. This concern goes hand in hand with demand for higher bandwidth which leads to need to develop new Compression Standards as VP9 or H.265/HEVC. This results in requirements for video quality assessment as one main part of the multimedia stream. Compression together with transmission link imperfection are two major factors that influence the quality. This paper deals with assessment of impact of VP9 Compression Standard on the video quality using different subjective metrics. The evaluation is done for two types of sequences with Full HD resolution depending on content. The main outcome obtained from the results is the determination of the threshold in the means of point where the quality do not rise so swift. This threshold was set between 5 and 7 Mbps. After this threshold the observers did not evaluate the quality of both sequence with quite higher marks which means there is no need to compress the sequences to higher bitrates than to 7 Mbps. These results are part of a new model that is still being created and will be used for predicting the video quality in networks based on IP.

  • Subjective Video Quality Assessment of H.265 Compression Standard for Full HD Resolution
    Advances in Electrical and Electronic Engineering, 2015
    Co-Authors: Miroslav Uhrina, Michal Malicek, Martin Vaculik
    Abstract:

    Recently increasing interest in multimedia services leads to requirements for quality assessment, especially in the video domain. There are many factors that influence the video quality. Compression technology and transmission link imperfection can be considered as the main ones. This paper deals with the assessment of the impact of H.265/HEVC Compression Standard on the video quality using subjective metrics. The evaluation is done for two types of sequences with Full HD resolution depending on content. The paper is divided as follows. In the first part of the article, a short characteristic of the H.265/HEVC Compression Standard is written. In the second part, the subjective video quality methods used in our experiments are described. The last part of this article deals with the measurements and experimental results. They showed that quality of sequences coded between 5 and 7 Mbps is for observers sufficient, so there is no need for providers to use higher bitrates in streaming than this threshold. These results are part of a new model that is still being created and will be used for predicting the video quality in networks based on IP.

  • TSP - The impact of bitrate and packet loss on the video quality of H.264/AVC Compression Standard
    2015 38th International Conference on Telecommunications and Signal Processing (TSP), 2015
    Co-Authors: Miroslav Uhrina, Martin Vaculik
    Abstract:

    This article focuses on the relationship between the bitrate of the H.264/AVC Compression Standard and the packet loss and its impact on the video quality. This testing is the second part of the research of a global video quality factor which will rate the impact of the Compression and the transmission link on the video quality. In the first part of this paper a short characteristic of the H.264/AVC Compression Standard is written. The second part deals with the objective video quality assessment. In the last part the measurements and experimental results are described.

Charilaos Christopoulos - One of the best experts on this subject based on the ideXlab platform.

  • jpeg2000 the upcoming still image Compression Standard
    Pattern Recognition Letters, 2001
    Co-Authors: A N Skodras, Charilaos Christopoulos, Touradj Ebrahimi
    Abstract:

    With the increasing use of multimedia technologies, image Compression requires higher performance as well as new features. To address this need in the specific area of still image encoding, a new Standard is currently being developed, the JPEG2000. It is not only intended to provide rate-distortion and subjective image quality performance superior to existing Standards, but also to provide functionality that current Standards can either not address efficiently or not address at all.

  • jpeg2000 the new still picture Compression Standard
    ACM Multimedia, 2000
    Co-Authors: Charilaos Christopoulos, Touradj Ebrahimi, A N Skodras
    Abstract:

    This paper presents an overview of the upcoming JPEG2000 still picture Compression Standard. JPEG2000 is not only intended to provide rate-distortion and subjective image quality performance superior to existing JPEG Standard, but to also provide functionality that the current JPEG Standard can either not address efficiently nor address at all. Lossless and lossy Compression, encoding of very large images, progressive transmission by pixel accuracy and by resolution, robustness to the presence of bit-errors and region-of-interest coding, are some representative examples of its features.

  • ACM Multimedia Workshops - JPEG2000: the new still picture Compression Standard
    Proceedings of the 2000 ACM workshops on Multimedia - MULTIMEDIA '00, 2000
    Co-Authors: Charilaos Christopoulos, Touradj Ebrahimi, A N Skodras
    Abstract:

    This paper presents an overview of the upcoming JPEG2000 still picture Compression Standard. JPEG2000 is not only intended to provide rate-distortion and subjective image quality performance superior to existing JPEG Standard, but to also provide functionality that the current JPEG Standard can either not address efficiently nor address at all. Lossless and lossy Compression, encoding of very large images, progressive transmission by pixel accuracy and by resolution, robustness to the presence of bit-errors and region-of-interest coding, are some representative examples of its features.

A N Skodras - One of the best experts on this subject based on the ideXlab platform.

  • jpeg2000 the new still picture Compression Standard
    ACM Multimedia, 2000
    Co-Authors: Charilaos Christopoulos, Touradj Ebrahimi, A N Skodras
    Abstract:

    This paper presents an overview of the upcoming JPEG2000 still picture Compression Standard. JPEG2000 is not only intended to provide rate-distortion and subjective image quality performance superior to existing JPEG Standard, but to also provide functionality that the current JPEG Standard can either not address efficiently nor address at all. Lossless and lossy Compression, encoding of very large images, progressive transmission by pixel accuracy and by resolution, robustness to the presence of bit-errors and region-of-interest coding, are some representative examples of its features.

  • ACM Multimedia Workshops - JPEG2000: the new still picture Compression Standard
    Proceedings of the 2000 ACM workshops on Multimedia - MULTIMEDIA '00, 2000
    Co-Authors: Charilaos Christopoulos, Touradj Ebrahimi, A N Skodras
    Abstract:

    This paper presents an overview of the upcoming JPEG2000 still picture Compression Standard. JPEG2000 is not only intended to provide rate-distortion and subjective image quality performance superior to existing JPEG Standard, but to also provide functionality that the current JPEG Standard can either not address efficiently nor address at all. Lossless and lossy Compression, encoding of very large images, progressive transmission by pixel accuracy and by resolution, robustness to the presence of bit-errors and region-of-interest coding, are some representative examples of its features.