Lossless JPEG

About: Lossless JPEG is a research topic. Over the lifetime, 2415 publications have been published within this topic receiving 51110 citations. The topic is also known as: Lossless JPEG & .jls.

Multicomponent transforms for motion JPEG 2000 applications

Abstract: Motion JPEG 2000 (M-JPEG 2000) has been developed as a new video standard exploiting the still image codec JPEG 2000. The main benefits of this standard, as high scalability and quick random access to the frames, are paid in terms of compression efficiency. In order to fix this drawback while maintaining all previously mentioned features, we propose a novel technique to exploit the multicomponents transform feature of JPEG 2000 part-2; this is achieved taking advantage of the temporal correlation, while maintaining a relatively low complexity in comparison with motion compensation based video codecs.

Efficient SecuredLosslessCompression ofMedical Images - UsingModifiedRunlength Coding for Character Representation

Abstract: Lossless compression schemeswithsecure transmission playakeyroleintelemedicine applications that helpsin accurate diagnosis and research. Traditional cryptographic algorithms fordatasecurity arenotfast enough toprocess vastamountofdata. HenceanovelSecured lossless compression approach proposed inthispaperisbasedon reversible integer wavelet transform, SPIHTalgorithm, new modified runlength coding forcharacter representation and selective bitscrambling. Theuseofthelifting scheme allows to generate truly lossless integer-to-integer wavelet transforms. Images arecompressed/decompressed bywell-known SPIHT algorithm. Theproposed modified runlength coding greatly improves thecompression performance andalso increases the security level. Thisworkemploys scrambling method whichis fast, simple toimplement anditprovides security. Lossless compression ratios anddistortion performance ofthis proposed method arefound tobebetter thanother lossless techniques. Keywords - SPIHT algorithm, lifting scheme,lossless compression, reversible integer wavelet transform, secure transmission, selective bitscrambling, modified runlength coding.

A lossless hybrid shape-adaptive image coder

Abstract: Lossless image compression continues to be the focus of the medical picture archiving system designers because of the possibility of reducing the bandwidth required to transmit medical images. The lossless Differential Pulse Code Modulation (DPCM) and Hierarchical Interpolation (HINT) have been suggested as solutions to this problem. However, there are limitations due to the inability of these schemes to adapt to local image statistics. Efforts to alleviate this problem can be seen in various adaptive schemes found in the literature. This paper introduces a new adaptive DPCM (ADPCM) scheme based on the shape of the region of support (ROS) of the predictor. The shape information of the local region is obtained through a universal Vector Quantization (VQ) scheme. The proposed lossless encoding scheme switches predictor type depending on the local shape. Simulation results show that improvements of about 0.4 bits/ pixel over basic DPCM and 0.2 bits/pixel over HINT can be obtained. Comparison with lossless JPEG indicates that the proposed scheme can cope more easily with the changes in local image statistics. The computation required is moderate, since a universal VQ is used in encoding the shape information.

Post-Segmentation Approach for Lossless Region of Interest Coding

Abstract: This paper presents a lossless region of interest coding technique that is suitable for interactive telemedicine over networks. The new encoding scheme allows a server to transmit only a part of a compressed image data progressively as a client requests it. This technique is different from region scalable coding in JPEG2000 since it does not define region of interest (ROI) when encoding occurs. In the proposed method, the image is fully encoded and stored in the server. It also allows a user to select a ROI after the compression is done. This feature is the main contribution of research. The proposed coding method achieves the region scalable coding by using the integer wavelet lifting, successive quantization, and partitioning that rearranges the wavelet coefficients into subsets. Each subset that represents a local area in an image is then separately coded using run-length and entropy coding. In this paper, we will show the benefits of using the proposed technique with examples and simulation results.

Performance Analysis of Wavelet Based Transforms in JPEG

Abstract: In this paper, a performance analysis of different transforms DCT, DWT and a combined approach of DCT and DWT is used to compress a digital image. JPEG is the first international digital image compression standard for continuous-tone still images, both grey scale and color. JPEG is a transform coder, which uses DCT as the default transform. It has been proved that we can easily plug in Discrete Wavelet Transform (DWT) to JPEG standard with minimal changes in the basic operations. The experimental results show that DWT based JPEG gives better quality at higher bit-rates than DCT based JPEG. Since the bit-rate is less, DCT-JPEG outperforms DWT JPEG. But the computational complexity of DWT-JPEG is much higher than that of DCT-JPEG. A combination of DCT and DWT transforms can be used to reduce the computational complexity and also to get better quality image than DCT-JPEG at higher bit-rates.