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Distortionless data hiding based on integer wavelet transform

ELECTRONICS LETTERS 2002年第25期38卷 1646-1648页

作者： Xuan, GR Zhu, J Chen, JD Shi, YQ Ni, ZC Su, W Tongji Univ Dept Comp Sci Shanghai Peoples R China New Jersey Inst Technol Dept Elect & Comp Engn Newark NJ 07102 USA

A novel distortionless image data hiding algorithm based on integer wavelet transform that can invert the stego-image into the original image without any distortion after the hidden data are extracted is proposed. This algorithm hides data into one (or more) middle bit-plane(s) of the integer wavelet transform coefficients in the middle and high frequency subbands. It can embed much more data compared with the existing distortionless data hiding techniques and satisfy the imperceptibility requirement. The image histogram modification is used to prevent greyscales from possible overflowing. Experimental results have demonstrated the validity of the algorithm.

关键词： wavelet transforms transform coding image and video coding Integral transforms in numerical analysis stego-image inversion integer wavelet transform image coding feature extraction data encapsulation distortionless image data hiding algorithm image histogram modification integer wavelet transform coefficients high frequency subbands middle frequency subbands Data security Computer vision and image processing techniques invertible data hiding

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Low resolution region discriminator for wavelet coding

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ELECTRONICS LETTERS 2001年第12期37卷 748-749页

作者： Syed, YF Rao, KR Cable Televis Labs Louisville CO 80027 USA Univ Texas Dept Elect Engn Arlington TX 76019 USA

A wavelet block chain (WBC) method is used in the initial coding of the low-low subband created by a wavelet transform to separate and label homogenous regions of the image which require no additional overhead in the bitstream. This information is then used to enhance the coding performance in a modified wavelet based coder. This method uses a two stage ZTE/SPIHT entropy coder (called a homogenous connected-region interested ordered transmission coder) to create a bitstream with properties of progressive transmission, scalability, and perceptual optimisation after a minimum bit rate is reached. Simulation results show good scalable low bit rate (0.04-0.4bpp) compression, comparable to a SPIHT coder, but with better perceptual quality due to use of the region based information acquired by the WBC method.

关键词： perceptual quality low-low subband minimum bit rate Integral transforms in numerical analysis wavelet coding perceptual optimisation wavelet block chain bitstream Codes homogenous regions entropy codes region based information image coding two stage ZTE/SPIHT entropy coder Computer vision and image processing techniques wavelet transforms homogenous connected-region interested ordered transmission coder image and video coding progressive transmission low resolution region discriminator image resolution coding performance scalability

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Backward compatible user-defined data insertion into MPEG-4 bitstreams

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ELECTRONICS LETTERS 2000年第12期36卷 1036-1037页

作者： Worrall, ST Sadka, AH Sweeney, P Kondoz, AM Univ Surrey Ctr Commun Syst Res Guildford GU2 7HX Surrey England

It is often useful to provide information related to a video bitstream that is unsupported by the official standard. A method is described by which data can br: inserted in an MPEG-4 bitstream [1], while still retaining compatibility with standard MPEG-4 decoders. Its effectiveness is demonstrated by results from insertion of cyclic redundancy check (CRC) codes.

关键词： code standards user-defined data insertion image and video coding data compression CRC code insertion standard MPEG-4 decoder compatibility Codes synchronisation error detection codes resynchronisation code video bitstream cyclic redundancy check codes video coding decoding backward compatible data insertion MPEG-4 bitstreams

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Fast rate-distortion optimisation algorithm for motion-compensated transform coding of video

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ELECTRONICS LETTERS 2000年第4期36卷 305-306页

作者： Shen, JD Chan, WY IIT Dept Elect & Comp Engn Chicago IL 60616 USA

A reduced-complexity but effective search scheme for rate-distortion (RD) optimisation of motion vector and displaced-frame-difference coding is proposed. Through predicting the relative order of the RD-Lagrange rests, a large proportion of suboptimal displacement Vector positions are eliminated. In comparison with a popular H.263 test model, the proposed scheme leads to a similar to 0.5dB improvement in the peak signal-to-noise ratio.

关键词： transform coding rate distortion theory peak signal-to-noise ratio image and video coding suboptimal displacement vector positions H.263 test model rate-distortion optimisation algorithm motion-compensated transform coding video signal processing RD-Lagrange costs motion compensation video coding displaced-frame-difference coding

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H.266/VVC fast intra prediction using Sobel edge features

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ELECTRONICS LETTERS 2021年第1期57卷 11-13页

作者： Yang, Shih-Hsuan Hsiao, Sheng-Jung Natl Taipei Univ Technol Dept Comp Sci & Informat Engn Taipei Taiwan

Versatile video coding is the next-generation video coding standard. Compared with the previous high efficiency video coding standard, versatile video coding reduces 30% or more bitrate but requires significantly higher encoding complexity. This Letter proposes a fast intra prediction algorithm for partition type selection and mode decision of versatile video coding. The Sobel operator is employed to extract the gradient intensity and edge direction of coding blocks. Early skip conditions for partition types are developed based on the dominant edge indicated by block gradients. The intra prediction modes are further restricted to the directions close to the edge orientation of a coding block. Experimental results indicate that the proposed method in the Intra-only configuration saves 34.66% of the encoding time with a slight (0.61%) increase in Bjontegaard delta bit rate, which achieves the best tradeoff between acceleration and quality among all the investigated methods.

关键词： image and video coding image recognition Computer vision and image processing techniques video signal processing

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Low-power VLSI architectures for 3D discrete cosine transform (DCT) 46

Low-power VLSI architectures for 3D discrete cosine transfor...

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46th IEEE International Midwest Symposium on Circuits and Systems

作者： Saponara, S Fanucci, L Terreni, P Univ Pisa Dept Informat Engn I-56122 Pisa Italy

ISBN: (纸本)0780382943

The 3D Discrete Cosine Transform (DCT) extends the energy compaction properties of conventional 2D-DCT to integral 3D images and to the spatio-temporal coding of 2D video sequences. This paper addresses the problem of a cost-effective VLSI realization of the 3D-DCT and its inverse (IDCT). The VLSI design space is exploited at different levels of abstraction (algorithm, architecture, circuit, technology) to devise a family of 3D-DCT/IDCT macrocells that, implemented in a 0.18 mu m CMOS technology, support the real-time processing of main video formats with different trade-offs between circuit complexity and power consumption. A clock-gating design strategy further reduces power consumption according to input signal statistics.

关键词： VLSI design DCT image and video coding low-power circuits

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INTEGRAL imageS COMPRESSION SCHEME BASED ON VIEW EXTRACTION 23

INTEGRAL IMAGES COMPRESSION SCHEME BASED ON VIEW EXTRACTION

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23rd European Signal Processing Conference (EUSIPCO)

作者： Dricot, A. Jung, J. Cagnazzo, M. Pesquet, B. Dufaux, F. Orange Labs Paris France Telecom ParisTech CNRS LTCI Inst Mines Telecom Paris France

ISBN: (纸本)9780992862633

Integral imaging is a glasses-free 3D video technology that captures a light-field representation of a scene. This representation eliminates many of the limitations of current stereoscopic and autostereoscopic techniques. However, integral images have a large resolution and a structure based on micro-images which is challenging to encode. In this paper a compression scheme for integral images based on view extraction is proposed. Average BD-rate gains of 15.7% and up to 31.3% are reported over HEVC. Parameters of the proposed coding scheme can take a large range of values. Results are first provided with an exhaustive search of the best configuration. Then an RD criterion is proposed to avoid exhaustive search methods, saving runtime while preserving the gains. Finally, additional runtime savings are reported by exploring how the different parameters interact.

关键词： Integral Imaging Plenoptic Imaging Holoscopy image and video coding View Extraction

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High Dynamic Range image & video Compression A Review

High Dynamic Range Image & Video Compression A Review

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18th International Conference on Digital Signal Processing (DSP)

作者： Zhang, Yang Agrafiotis, Dimitris Bull, David R. Univ Bristol Dept Elect & Elect Engn Bristol Avon England

ISBN: (纸本)9781467358057

High Dynamic Range (HDR) imaging technologies can provide high levels of immersion through a dynamic range that meets and even exceeds the instantaneous range of the Human Visual System (HVS). This increase in the level of immersion comes at the cost of significantly higher bit-rate requirements compared to those associated with conventional imaging technologies. As a result, efficient HDR-relevant coding solutions have to be developed. In this paper, we present a review of existing HDR image and video coding methods, thus establishing the current state of the art. We additionally present some of our own recent results in this area.

关键词： High Dynamic Range Imaging image and video coding Human Visual System Backward compatibility Visual perception Visual masking Quality metrics

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Compression of compound images and video for enabling rich media in embedded systems

Compression of compound images and video for enabling rich m...

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Conference on Visual Communications and image Processing 2004

作者： Said, A Hewlett Packard Labs Cupertino CA 95014 USA

ISBN: (纸本)0819452114

It is possible to improve the features supported by devices with embedded systems by increasing the processor computing power, but this always results in higher costs, complexity, and power consumption. An interesting alternative is to use the growing networking infrastructures to do remote processing and visualization, with the embedded system mainly responsible for communications and user interaction. This enables devices to behave as if much more "intelligent" to users, at very low costs and power. In this article we explain how compression can make some of these solutions more bandwidth-efficient, enabling devices to simply decompress very rich graphical information and user interfaces that had been rendered elsewhere. The mixture of natural images and video with text, graphics, and animations simultaneously in the same frame is called compound video. We present a new method for compression of compound images and video, which is able to efficiently identify the different components during compression, and use an appropriate coding method. Our system uses lossless compression for graphics and text, and, on natural images and highly detailed parts, it uses lossy compression with dynamically varying quality. Since it was designed for embedded systems with very limited resources, and it has small executable size, and low complexity for classification, compression and decompression. Other compression methods (e.g., MPEG) can do the same, but are very inefficient for compound content. High-level graphics languages can be bandwidth-efficient, but are much less reliable (e.g., supporting Asian fonts), and are many orders of magnitude more complex. Numerical tests show the very significant gains in compression achieved by these systems.

关键词： embedded systems image and video coding mixed raster content remote visualization

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Origins of the Zigzag Scan in Transform-Based Picture coding 47

Origins of the Zigzag Scan in Transform-Based Picture Coding

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Conference on Applications of Digital image Processing XLVII

作者： Reznik, Yuriy A. Brightcove Inc Boston MA 02210 USA

ISBN: (纸本)9781510679344;9781510679351

We review the history of the development of one of the most iconic tools in image and video coding - the zigzag scan. Despite its simplicity, we will show that its development was a non-trivial process that took several years, multiple iterations, and multiple ideas that eventually led to the formation of its final "zigzag" shape. Remarkably, we also discover that early variants of the zigzag scan appeared before the invention of the DCT, intra-predictors, and many other techniques in image and video coding algorithms. It is one of the oldest and most fundamental techniques in this context. This paper also traces the evolution of image and video codec architectures over the last six decades and brings examples of uses of the zigzag scan in modern-era image and video coding standards.

关键词： image and video coding Fourier analysis Boas-Kac-Lukosz inequalities DFT DCT KLT zigzag scan

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