Standard JPEG Research Articles

JPEG2000-Compatible Scalable Scheme for Wavelet-Based Video Coding

We present a simple yet efficient scalable scheme for wavelet-based video coders, able to provide on-demand spatial, temporal, and SNR scalability, and fully compatible with the still-image coding standard JPEG2000. Whereas hybrid video coders must undergo significant changes in order to support scalability, our coder only requires a specific wavelet filter for temporal analysis, as well as an adapted bit allocation procedure based on models of rate-distortion curves. Our study shows that scalably encoded sequences have the same or almost the same quality than nonscalably encoded ones, without a significant increase in complexity. A full compatibility with Motion JPEG2000, which tends to be a serious candidate for the compression of high-definition video sequences, is ensured.

Evaluation of Mammographic Phantom Images Using JPEG2000 Image Compression

Purpose: To determine the usefulness of compression standard JPEG2000 for compression of mammographic images. Materials and Methods: Image of a mammographic phantom was compressed using JPEG2000 at ratios of 10:1, 20:1, 30:1, 40:1, 50:1 and 60:1. The sizes of the images were compared, and scores were recorded by counting the numbers of fibers, groups of specks and masses seen in each phantom image. More than four fibers, three groups of specks and three masses and a total score of 10 were considered acceptable. Results: The size of a DICOM image was 17,042 KB, a TIFF image was 8,324 KB, the original JPEG image was 1,506 KB and the most compressed image (50:1) above an acceptable total score of 10 was 43 KB. In each category, the compression image of fiber was acceptable up to compression ratio of 50:1 (score of 5), groups of specks was acceptable up to 60:1 (score of 3) and mass was acceptable up to 50:1 (score of 3.5). The total score, which was acquired by adding up the individual scores of all three categories, for a compression ratio of 50:1 was 12 and was acceptable, but the total score for 60:1 was 8 and was not acceptable. Conclusion: The compression standard JPEG2000 is an efficient means for compressing mammographic images at high ratios without compromising diagnostic value.

Burrows-Wheeler based JPEG

Recently, the use of the Burrows-Wheeler method for data compression has been expanded. A method of enhancing the compression efficiency of the common JPEG standard is presented in this paper, exploiting the Burrows-Wheeler compression technique. The paper suggests a replacement of the traditional Huffman compression used by JPEG by the Burrows-Wheeler compression. When using high quality images, this replacement will yield a better compression ratio. If the image is synthetic, even a poor quality image can be compressed better.

Matrix Factorizations for Parallel Integer Transformation

Integer mapping is critical for lossless source coding and has been used for multicomponent image compression in the new international image compression standard JPEG 2000. In this paper, starting from block factorizations for any nonsingular transform matrix, we introduce two types of parallel elementary reversible matrix (PERM) factorizations which are helpful for the parallelization of perfectly reversible integer transforms. With improved degree of parallelism and parallel performance, the cost of multiplications and additions can be, respectively, reduced to O(logN) and O(log2N) for an N by N transform matrix. These make PERM factorizations an effective means of developing parallel integer transforms for large matrices. We also present a scheme to block the matrix and allocate the load of processors for efficient transformation

Comparative Survey of the DCT and the Wavelet Transforms for Image Compression

Abstract In the framework of the image compression by transform coding, we studied two transformation techniques, respectively, used in the JPEG and JPEG2000 standards: the discrete cosine transform (DCT) and the wavelets transform (WT). We also studied the influence of different coding techniques on the compression rate.We compare the performances of different wavelets. The set of the techniques that we implemented have been applied on different types of images.We verified the compromise that exists between the compression rate and the quality of the reconstructed image.We noted that when we apply the wavelet transform, we succeeded with best results of those found by the use of the DCT.We note also that the quality of reconstruction is better as we increase the order of the filter associated to the Daubechies wavelets.

A Flexible Hardware JPEG 2000 Decoder for Digital Cinema

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> &lt;?Pub _touchup WordspNominal="1.6" WordspMinimum="1.3" WordspMaximum="2.9"?&gt;The image compression standard JPEG 2000 proposes a large set of features that is useful for today's multimedia applications. Unfortunately, it is much more complex than older standards. Real-time applications, such as digital cinema, require a specific, secure, and scalable hardware implementation. In this paper, a decoding scheme is proposed with two main characteristics. First, the complete scheme takes place in a field-programmable gate array without accessing any external memory, allowing integration in a &lt;?Pub /_touchup?&gt;secured system. Second, a customizable level of parallelization allows to satisfy a broad range of constraints, depending on the signal resolution. The resulting architecture is therefore ready to meet upcoming digital cinema specifications. </para>

Tiling of the Wavelet Lowpass Subbands for Progressive Browsing of Images

This letter presents a new tiling scheme to achieve multiresolution and subregion image access as well as progressive retrieval, such as drill-down browsing and remote zooming/panning. This new scheme is based on the standard JPEG2000 algorithm. While JPEG2000 only divides the original image into tiles, the presented scheme divides each coarse version of the image into equal-sized tiles and reorders the wavelet coefficients in each of the steps of the analysis process. This new scheme avoids the problems associated with the traditional tiling, as used in JPEG2000, getting better lossy and lossless compression ratios, reducing disk or network latency, and improving the quality of the image.

NNIC—neural network image compressor for satellite positioning system

We have developed an algorithm, based on novel techniques of data compression and neural networks for the optimal positioning of a satellite. The algorithm is described in detail, and examples of its application are given. The heart of this algorithm is the program NNIC—neural network image compressor. This program was developed for compression color and grayscale images with artificial neural networks (ANNs). NNIC applies three different methods for compression. Two of them are based on neural networks architectures—multilayer perceptron and kohonen network. The third is based on a widely used method of discrete cosine transform, the basis for the JPEG standard. The program also serves as a tool for determining numerical and visual quality parameters of compression and comparison between different methods. A number of advantages and disadvantages of the compression using ANNs were discovered in the course of the present research, some of them presented in this report. The thrust of the report is the discussion of ANNs implementation problems for modern platforms, such as a satellite positioning system that include intensive image flowing and processing.

VLSI Algorithms and architectures for JPEG2000

In this paper, we presented VLSI algorithms and architectures for JPEG2000. JPEG2000 is the new standard for image compression. We briefly described the core algorithms for JPEG2000 standard and its several features desirable in many interactive multimedia applications. The core compression algorithm has three major components - discrete wavelet transform (DWT), fractional bit plane coding (BPC), and context adaptive binary arithmetic coding. DWT and BPC are very computationally, as well as memory expensive operations. As a result, special purpose VLSI implementations of these algorithms are desirable for many devices to compress large size images in real time. Traditionally, the DWT is realized by convolution based finite impulse response (FIR) filtering techniques. However, Lifting based implementation of DWT is found to be computationally efficient and suitable for VLSI implementations. The basic principle behind the lifting based scheme is to decompose the finite impulse response filters in wavelet transform into a finite sequence of simple filtering steps. Lifting based DWT implementation have been recommended in JPEG2000 standard. Consequently, this has become an area of active research and several architectures have been proposed in recent years. In this paper, we reviewed some of the key lifting architectures suitable for VLSI implementation. The embedded block coding with optimized truncation (EBCOT) algorithm has been adopted for computation of BPC in JPEG2000. This algorithm is complex and inefficient to implement in a general purpose machine. We have described a special purpose architecture suitable for VLSI implementation of EBCOT algorithm. We also reviewed some elegant architectures in the literature which exploit the underlying data and computational parallelism inherent in the EBCOT algorithms. We also presented a top-level systems architecture for VLSI implementation of the JPEG2000 standard.

VLSI Algorithms and architectures for JPEG2000

In this paper, we presented VLSI algorithms and architectures for JPEG2000. JPEG2000 is the new standard for image compression. We briefly described the core algorithms for JPEG2000 standard and its several features desirable in many interactive multimedia applications. The core compression algorithm has three major components - discrete wavelet transform (DWT), fractional bit plane coding (BPC), and context adaptive binary arithmetic coding. DWT and BPC are very computationally, as well as memory expensive operations. As a result, special purpose VLSI implementations of these algorithms are desirable for many devices to compress large size images in real time. Traditionally, the DWT is realized by convolution based finite impulse response (FIR) filtering techniques. However, Lifting based implementation of DWT is found to be computationally efficient and suitable for VLSI implementations. The basic principle behind the lifting based scheme is to decompose the finite impulse response filters in wavelet transform into a finite sequence of simple filtering steps. Lifting based DWT implementation have been recommended in JPEG2000 standard. Consequently, this has become an area of active research and several architectures have been proposed in recent years. In this paper, we reviewed some of the key lifting architectures suitable for VLSI implementation. The embedded block coding with optimized truncation (EBCOT) algorithm has been adopted for computation of BPC in JPEG2000. This algorithm is complex and inefficient to implement in a general purpose machine. We have described a special purpose architecture suitable for VLSI implementation of EBCOT algorithm. We also reviewed some elegant architectures in the literature which exploit the underlying data and computational parallelism inherent in the EBCOT algorithms. We also presented a top-level systems architecture for VLSI implementation of the JPEG2000 standard.

Adaptive downsampling to improve image compression at low bit rates

At low bit rates, better coding quality can be achieved by downsampling the image prior to compression and estimating the missing portion after decompression. This paper presents a new algorithm in such a paradigm, based on the adaptive decision of appropriate downsampling directions/ratios and quantization steps, in order to achieve higher coding quality with low bit rates with the consideration of local visual significance. The full-resolution image can be restored from the DCT coefficients of the downsampled pixels so that the spatial interpolation required otherwise is avoided. The proposed algorithm significantly raises the critical bit rate to approximately 1.2 bpp, from 0.15-0.41 bpp in the existing downsample-prior-to-JPEG schemes and, therefore, outperforms the standard JPEG method in a much wider bit-rate scope. The experiments have demonstrated better PSNR improvement over the existing techniques before the critical bit rate. In addition, the adaptive mode decision not only makes the critical bit rate less image-independent, but also automates the switching coders in variable bit-rate applications, since the algorithm turns to the standard JPEG method whenever it is necessary at higher bit rates.

An Efficient Context-Based BPGC Scalable Image Coder

In this brief, we present an image entropy coder, context-based bit-plane Golomb coder (CB-BPGC), for wavelet-based scalable image coding. CB-BPGC follows the idea of the state-of-the-art image coding standard JPEG2000 entropy coding to apply the rate-distortion optimization algorithm after block coding. However, it explores a more efficient block coding where statistical properties of the block coefficients are considered. Compression ratio and error resilience performances of the proposed coder are evaluated, and the experimental results show that, compared with the JPEG2000, it achieves better lossless and lossy coding performance with lower complexity and greater resilience to transmission errors when simulated on the wireless Rayleigh fading channel

A new approach for optical colored image compression using the JPEG standards

Image compression consists in reducing information volume representing an image. Elimination of redundancies and non-pertinent information enables memory space minimization and thus faster data transmission. The present work aims to improve the quality of the compressed image while minimizing the time required for compression by using the principle of coherent optics. We present an optical adaptation of the method of JPEG compression technique for binary, gray-level and color images. Illustrative simulations will be given at the end to validate our architecture and to evaluate the performance on different types of images (binary, gray and color). An optical implementation setup is proposed and validated experimentally.

Fast search for best representations in multitree dictionaries

We address the best basis problem--or, more generally, the best representation problem: Given a signal, a dictionary of representations, and an additive cost function, the aim is to select the representation from the dictionary which minimizes the cost for the given signal. We develop a new framework of multitree dictionaries, which includes some previously proposed dictionaries as special cases. We show how to efficiently find the best representation in a multitree dictionary using a recursive tree-pruning algorithm. We illustrate our framework through several examples, including a novel block image coder, which significantly outperforms both the standard JPEG and quadtree-based methods and is comparable to embedded coders such as JPEG2000 and SPIHT.

Design of IIR orthogonal wavelet filter banks using lifting scheme

The lifting scheme is well known to be an efficient tool for constructing second generation wavelets and is often used to design a class of biorthogonal wavelet filter banks. For its efficiency, the lifting implementation has been adopted in the international standard JPEG2000. It is known that the orthogonality of wavelets is an important property for many applications. This paper presents how to implement a class of infinite-impulse-response (IIR) orthogonal wavelet filter banks by using the lifting scheme with two lifting steps. It is shown that a class of IIR orthogonal wavelet filter banks can be realized by using allpass filters in the lifting steps. Then, the design of the proposed IIR orthogonal wavelet filter banks is discussed. The designed IIR orthogonal wavelet filter banks have approximately linear phase responses. Finally, the proposed IIR orthogonal wavelet filter banks are applied to the image compression, and then the coding performance of the proposed IIR filter banks is evaluated and compared with the conventional wavelet transforms

A new algorithm for the embedding of a prediction mechanism into the JPEG2000 coding chain

In this paper, we propose the embedding of a prediction mechanism into a part of the coding structure of JPEG2000 image compression standard, in order to reduce the amount of bits sent to the arithmetic coder, without any significant changes into the standard architecture and without loosing performance. The prediction is based upon an innovative processing of the data structures used by the standard JPEG2000 in progressive coding and the addition of a Prediction Matrix, whose computation does not add any overhead at the decoder side. Experiments are performed to test the efficacy of the prediction mechanism, and results are compared to the standard JPEG2000 and other similar approaches. Tests are documented over a set of well-known images from literature, also against different kinds of added noise. Performance, in terms of saved bits are reported, and a new figure of merit is defined to test the efficiency of Prediction. The results prove that the new proposal overcomes the standard and other related approaches for the entire set of referenced images, with significant gain in synthetic images, also in presence of noise.

Efficient selective encryption for JPEG 2000 images using private initial table

In this paper, we propose an efficient selective encryption scheme for encrypting JPEG 2000 images. The proposed scheme uses a secret key and a mapping function to generate a private initial table to encrypt the selected DWT codeblocks in the entropy coding stage of JPEG 2000 coding scheme. Theoretical analysis and experimental results show that the proposed scheme can achieve various purposes of selective encryption and is computationally secure. Moreover, the proposed scheme does not decrease the compressibility of the standard JPEG 2000 coding scheme. The proposed selective encryption scheme is practical for applications of JPEG 2000 image protection.

Compression of interference patterns with application to phase-shifting digital holography

A compression method of phase-shifting digital holographic data is presented. Three interference patterns are recorded, and holographic information is extracted from them by phase-shifting interferometry. The scheme uses standard baseline Joint Photographic Experts Group (JPEG) or standard JPEG-2000 image compression techniques on the recorded interference patterns to reduce the amount of data to be stored. High compression rates are achieved for good reconstructed object image quality. The utility of the proposed method is experimentally verified with real holographic data. Results for compression rates using JPEG-2000 and JPEG of approximately 27 and 20, respectively, for a normalized root-mean-square error of approximately 0.7 are demonstrated.

Wavelet-based image processing

The 1990s witnessed an explosion of wavelet-based methods in the field of image processing. This article will focus primarily on wavelet-based image compression. We shall describe the connection between wavelets and vision, and how wavelet techniques provide image compression algorithms that are clearly superior to the present JPEG standard. In particular, the wavelet-based algorithms known as SPIHT, ASWDR, and the new standard JPEG2000, will be described and compared. Our comparison will show that, in many respects, ASWDR is the best algorithm. Applications to denoising will also be briefly referenced and pointers supplied to other references on wavelet-based image processing.

Still Image Compression with Mean-Residual Domain Adaptive Resolution Vector Quantization Technique

Abstract With the glowing importance of an advanced image processing methods for digital image, an efficient compression algorithm is increasingly important. In this paper we present progressive image compression algorithm based on Vector Quantization (VQ). Mean-Residual domain Adaptive Resolution Vector Quantization technique (MAR-VQ) that combines the adaptive resolution method with the mean-residual method has been developed. The adaptive resolution method changes the resolution of image adaptively according to the form of a pixel block texture in order to increase the performance of compound image compression. In addition, the mean-residual method was introduced as one of the additional techniques to increase continuous-tone image quality by VQ. As a result, MAR-VQ can realize much superior compression performance than the worldwide standard JPEG 2000.