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Enhanced interframe coding based on morphological segmentation

IEE PROCEEDINGS-VISION IMAGE AND SIGNAL PROCESSING 1997年第4期144卷 220-226页

作者： Czerepinski, PJ Bull, DR Univ Bristol Ctr Commun Res Image Commun Grp Bristol BS8 1UB Avon England

Morphological segmentation has been proposed as an attractive alternative to transform-based compression for interframe coding of digital video. Being a spatial approach, segmentation based coding eliminates the artefacts commonly associated with transform coding, such as ringing around sharp edges. One disadvantage of this method is that it can introduce spurious edges in the reconstructed video sequence. associated with the boundaries of the transmitted regions. The authors present a statistically derived smoothing algorithm that reduces this problem. In addition, a single-stage entropy coder for the update signal is proposed in place of the conventional two-stage algorithm. Comparisons are made between the performance of a traditional motion compensated DCT coder and segmentation based codecs (with and without smoothing) for CIF sequences at bit rates between 64 and 256 kbps. It is concluded that, at the bit rates under investigation, the segmentation based method yields improved subjective quality of the reconstructed video.

关键词： digital video interframe coding morphological segmentation transform coding smoothing algorithm

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A Lossless Compression Method for Medical Image Sequences Using JPEG-LS and interframe coding

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IEEE TRANSACTIONS ON INFORMATION TECHNOLOGY IN BIOMEDICINE 2009年第5期13卷 818-821页

作者： Miaou, Shaou-Gang Ke, Fu-Sheng Chen, Shu-Ching Chung Yuan Christian Univ Dept Elect Engn Chungli 32023 Taiwan

Hospitals and medical centers produce an enormous amount of digital medical images every day, especially in the form of image sequences, which requires considerable storage space. One solution could be the application of lossless compression. Among available methods, JPEG-LS has excellent coding performance. However, it only compresses a single picture with intracoding and does not utilize the interframe correlation among pictures. Therefore, this paper proposes a method that combines the JPEG-LS and an interframe coding with motion vectors to enhance the compression performance of using JPEG-LS alone. Since the interframe correlation between two adjacent images in a medical image sequence is usually not as high as that in a general video image sequence, the interframe coding is activated only when the interframe correlation is high enough. With six capsule endoscope image sequences under test, the proposed method achieves average compression gains of 13.3% and 26.3% over the methods of using JPEG-LS and JPEG2000 alone, respectively. Similarly, for an MRI image sequence, coding gains of 77.5% and 86.5% are correspondingly obtained.

关键词： interframe coding JPEG-LS lossless compression medical image sequences

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Application of leaky prediction to an interframe coding scheme

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART I-COMMUNICATIONS 1997年第4期80卷 20-28页

作者： Fujimura, M Kuroda, H Nakamura, A Faculty of Engineering Nagasaki University Nagasaki 852 Japan Fukui University Japan FACOM HITAC Ltd. Japan Nagasaki University Japan Inst. Electronics Info. and Commun. Information Processing Society Japan Kyushu Institute of Technology Kitakyushu Japan Faculty of Engineering Nagasaki University Japan Inst. Electronics Info. Commun. E. Inst. Television Engineers of Japan IEEE Japan Kyushu University Fukuoka Japan Department of Electronic Engineering Kumamoto Institute of Technology Japan Info. Processing Society of Japan Japan

In existing interframe predictive coding schemes, prediction error is minimized when the prediction factor is the same as the interframe correlation;methods based on complete prediction (with a prediction factor of 1) thus do not achieve optimum prediction. interframe leaky prediction was used in art effort to solve this problem. In the leaky prediction method proposed here, the frame type is determined from the interframe correlation and the leaky prediction coefficient, resulting in more efficient interframe ceding. Complete prediction is used for nonsignificant blocks, preventing the number of significant blocks from increasing. To eliminate errors, intraframe cyclic refresh was combined with leaky prediction, thus improving recovery of image quality. The new method is well suited to moving image coding in ATM systems. Software simulations demonstrate that the method is effective.

关键词： interframe coding leaky prediction hierarchical coding

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Application of leaky prediction to an interframe coding scheme

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Electronics and Communications in Japan (Part I: Communications) 1998年第4期80卷

作者： Makoto Fujimura Hideo Kuroda Akira Nakamura Faculty of Engineering Nagasaki University Nagasaki Japan 852

In existing interframe predictive coding schemes, prediction error is minimized when the prediction factor is the same as the interframe correlation; methods based on complete prediction (with a prediction factor of 1) thus do not achieve optimum prediction. interframe leaky prediction was used in an effort to solve this problem. In the leaky prediction method proposed here, the frame type is determined from the interframe correlation and the leaky prediction coefficient, resulting in more efficient interframe coding. Complete prediction is used for nonsignificant blocks, preventing the number of significant blocks from increasing. To eliminate errors, intraframe cyclic refresh was combined with leaky prediction, thus improving recovery of image quality. The new method is well suited to moving image coding in ATM systems. Software simulations demonstrate that the method is effective. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 1, 80 (4): 20–28, 1996

关键词： interframe coding leaky prediction hierarchical coding

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Single and double frame coding of speech LPC parameters using a lattice-based quantization scheme

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IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING 2006年第5期14卷 1624-1632页

作者： Lahouti, Farshad Fazel, Ahmad Reza Safavi-Naeini, Amir H. Khandani, Amir K. Univ Tehran Dept Elect & Comp Engn Tehran Iran Univ Waterloo Dept Elect & Comp Engn Waterloo ON N2L 3G1 Canada

A lattice-based scheme for the single-frame and the double-frame quantization of the speech line spectral frequency parameters is proposed. The lattice structure provides a low-complexity vector quantization framework, which is implemented using a trellis structure. In the single-frame scheme, the intraframe dependencies are exploited using a linear predictor. In the double-frame scheme, the parameters of two consecutive frames are jointly quantized and hence the interframe dependencies are also exploited. A switched scheme is also considered in which, lattice-based double-frame and single-frame quantization is performed for each two frame and the one which results in a lower distortion is chosen. Comparisons to the Split-VQ [13], the Multi-Stage VQ [12], the Trellis Coded Quantization [15], the interframe Block-Based Trellis Quantizer [17], and the interframe scheme used in IS-641 EFRC [26] and the GSM AMR codec [28] are provided. These results demonstrate the effectiveness of the proposed lattice-based quantization schemes, while maintaining a very low complexity. Finally, the issue of the robustness to channel errors is investigated.

关键词： CELP interframe coding intraframe coding lattice-based quantization LPC LSF quantization speech coding

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VLSI ARCHITECTURAL ASSESSMENT OF STANDARD IMAGE-coding SYSTEMS

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ANNALES DES TELECOMMUNICATIONS-ANNALS OF TELECOMMUNICATIONS 1991年第1-2期46卷 121-141页

作者： PRIVAT, G RENAUDIN, M CNET-Grenoble BP 98 Meylan Cedex

Image coding systems currently undergoing standardisation within ISO and CCITT are the final outcome of a process of incremental improvements to classical hybrid (transform-predictive) algorithms. The task of VLSI architecture synthesis for these complete systems is made somewhat awkward due to the unstructured, irregular and non-modular nature of these algorithms. An ad hoc methodology for pruning the architectural search space, directed by the goal of minimizing the overall internal memory, leads to a strongly control-flow solution, using a pipeline scheme more efficient than with the original signal-flow graph. A generic image coding processor using a parallel programmable architecture is another solution. It may be inferred that second generation image coding techniques should be designed with massive fine-grain parallelism in view, if they are to take advantage of the full potential of dedicated VLSI implementations.

关键词： IMAGE coding VLSI CIRCUIT CODEC PARALLEL PROCESSING ALGORITHM FIXED IMAGE MOVING IMAGE interframe coding INTRAFRAME coding METHODOLOGY

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Quantization of LSF parameters using a trellis modeling

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IEEE TRANSACTIONS ON SPEECH AND AUDIO PROCESSING 2003年第5期11卷 400-412页

作者： Lahouti, F Khandani, AK Univ Waterloo Dept Elect & Comp Engn Coding & Signal Transmiss Lab Waterloo ON N2L 3G1 Canada

An efficient Block-based Trellis Quantization (BTQ) scheme is proposed for the quantization of the Line Spectral Frequencies (LSF) in speech coding applications. The scheme is based on the modeling of the LSF intraframe dependencies with a trellis structure. The ordering property and the fact that LSF parameters are bounded within a range is explicitly incorporated in the trellis model. BTQ search and design algorithms are discussed and an efficient algorithm for the index generation (finding the index of a path in the trellis) is presented. Also the Sequential Vector Decorrelation Technique is presented to effectively exploit the intraframe correlation of LSF parameters within the trellis. Based on the proposed Block-based. Trellis Quantizer, two intraframe schemes and one interframe scheme are proposed. Comparisons to the Split-VQ [13], the Trellis Coded Quantization of LSF parameters [15], and the Multi-Stage VQ [12], as well as the interframe scheme used in IS-641 EFRC [28] and the GSM AMR codec [29] are provided. These results demonstrate that the proposed BTQ schemes outperform the above systems.

关键词： addressing CELP interframe coding intraframe coding LPC LSF quantization quantizer design speech coding trellis modeling

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OPTICAL COMPUTING TECHNIQUES FOR IMAGE VIDEO COMPRESSION

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PROCEEDINGS OF THE IEEE 1994年第6期82卷 948-954页

作者： YOSHIDA, A REIF, JH Dept. of Comput. Sci. Duke Univ. Durham NC

The advantage of optics is its capability of providing highly parallel operations in a three-dimensional space. In this paper, we propose optical architectures to execute various image compression techniques. We optically implement the following compression techniques: transform coding vector quantization video coding We show many generally used transform coding methods, for example, the cosine transform, can be implemented by a simple optical system. The transform coding can be carried out in constant time. Most of this paper is concerned with an innovative optical system for vector quantization using holographic associative matching. Limitations of conventional vector quantization schemes are caused by a large number of sequential searches through a large vector space. Holographic associative matching provided by multiple exposure holograms can offer advantageous techniques for vector-quantization-based compression schemes. Photorefractive crystals, which provide high-density recording in real time, are used as our holographic media. The reconstruction alphabet can be dynamically constructed through training or stored in the Photorefractive crystal in advance. Encoding a new vector can be carried out by holographic associative matching in constant time. An extension to interframe coding using optical block matching methods is also discussed. Most of the results in this paper were previously presented in our earlier paper [1].

关键词： block codes cosine transform encoding highly parallel operations holographic associative matching holography image coding image compression interframe coding optical block matching methods optical computing techniques optical information processing parallel processing photorefractive crystals reconstruction alphabet sequential searches transform coding transforms vector quantisation vector quantization video coding video compression video signals

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interframe LSF quantization for noisy channels

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IEEE TRANSACTIONS ON SPEECH AND AUDIO PROCESSING 1999年第5期7卷 495-509页

作者： Eriksson, T Lindén, J Skoglund, J Chalmers Univ Technol Dept Informat Theory SE-41296 Gothenburg Sweden

In linear predictive speech coding algorithms, transmission of linear predictive coding (LPC) parameters-often transformed to the line spectrum frequencies (LSF) representation-consumes' a large part of the total bit rate of the coder. Typically, the LSF parameters are highly correlated from one frame to the next, and a considerable reduction in bit rate can be achieved by exploiting this interframe correlation. However, interframe coding leads to error propagation if the channel is noisy, which possibly cancels the achievable gain. In this paper, several algorithms for exploiting interframe correlation of LSF parameters are compared. Especially, performance for transmission over noisy channels is examined, and methods to improve noisy channel performance are proposed, By combining an interframe quantizer and a memoryless "safety-net" quantizer, we demonstrate that the advantages of both quantization strategies can be utilized, and the performance for both noiseless and noisy channels improves. The results indicate that the best interframe method performs as good as a memoryless quantizing scheme, with 4 bits less per frame. Subjective listening tests have been employed that verify the results from the objective measurements.

关键词： interframe coding memory-based vector quantization robust coding spectrum coding speech coding vector quantization

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HYBRID CODERS WITH MOTION COMPENSATION

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MULTIDIMENSIONAL SYSTEMS AND SIGNAL PROCESSING 1992年第2-3期3卷 241-266页

作者： CHEN, CF PANG, KK Video Communication Group Department of Electrical and Computer Systems Engineering Monash University Clayton Australia

This paper investigates analytically the effects of motion compensation in a coder based on the observed properties of motion-compensated frame difference (MCFD) signals. The AR(1) processes with a given pixel-to-pixel autocorrelation coefficient will be used to model the interframe images. For interframe motion, each image is allowed to have both moving and nonmoving parts, with the moving parts executing a range of translational motion. From this mathematical model, the statistical characteristics of MCFD signals am derived. Motion compensation gain, 2-D intraframe transform gain, and hybrid gain are next evaluated to ascertain their suitability for the coding process. Experimental results on the Trevor sequence seem to confirm the model and conform with its analytical results.

关键词： MOTION COMPENSATION MOTION ESTIMATION interframe coding INTRAFRAME coding HYBRID coding CORRELATION MATRIX DISTORTION RATE FUNCTION

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