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.

Joint Source-Channel Coding of JPEG 2000 Image Transmission Over Two-Way Multi-Relay Networks

Abstract: In this paper, we develop a two-way multi-relay scheme for JPEG 2000 image transmission. We adopt a modified time-division broadcast cooperative protocol, and derive its power allocation and relay selection under a fairness constraint. The symbol error probability of the optimal system configuration is then derived. After that, a joint source-channel coding (JSCC) problem is formulated to find the optimal number of JPEG 2000 quality layers for the image and the number of channel coding packets for each JPEG 2000 codeblock that can minimize the reconstructed image distortion for the two users, subject to a rate constraint. Two fast algorithms based on dynamic programming and branch and bound are then developed. Simulation demonstrates that the proposed JSCC scheme achieves better performance and lower complexity than other similar transmission systems.

FPGA based simple and fast JPEG encryptor

Abstract: The efficient transmission of images at low bit rate with high security has gained momentum due to recent explosion in networking and multimedia applications. Mixing several existing standard encryption techniques with image encoding tend to change the bit rate greatly. In this paper, FPGA implementation of a novel image encryption algorithm, based on block and symbol scrambling is proposed as a part of JPEG image encoding scheme to meet four major requirements: (1) to provide temporal security, (2) to preserve the overall bit rate with negligible overhead, (3) remain complaint with the JPEG file format, (4) fast and less complex implementation for real time applications. Implementation of the algorithm in an efficient manner with low complexity is a requirement for real time tactical security applications. The algorithm is implemented on STRATIX II and IV FPGAs using only 1 % extra hardware for encryption than that of the basic JPEG. Further, the JPEG implementation without encryption is competitive with other implementations available in literature. The implemented encryption module can be used in the image transmission system for secure image coding and tactical communications.

Compressed File Length Predicts Search Time and Errors on Visual Displays

Abstract: Search times and errors were recorded for targets (a triangle or trapezoid) in marine radar, chart, and radar-chart overlay bitmap computer displays. Lossless JPEG and ZIP compressed file lengths were obtained for each display. The two types of file length were correlated and they predicted both the maximum time to search each display and the number of errors made per search. Compressed file length is analogous to algorithmic complexity, a theoretical measure of bit string complexity. It predicts both subjective complexity judgments (previous research) and search performance (this study) for a set of static marine electronic displays. The data suggest that compressed file length will predict minimum anticipated performance in a range of applied visual search tasks

A method of extracting embedded binary data from JPEG bitstreams using standard JPEG decoder

Abstract: We proposed a method for embedding binary data into JPEG bitstreams and extracting embedded data from JPEG bitstreams using the standard JPEG decoder. In the proposed method, we can decode the image from the embedded binary data JPEG bitstreams first using the traditional standard JPEG decoder, and then we can extract the embedded binary data perfectly by the post-processing from the decoded JPEG image. For the post-processing, we use only the decoded image data to extract the embedded binary data. Namely, we do not need any kind of particular parameters, which are used for JPEG decoding, such as quantization table value. Thus, we can use the traditional standard JPEG decoder for the pre-processing of extracting binary data. Furthermore, we address the effect of the calculation bit accuracy of the DCT and inverse discrete cosine transform (IDCT) for extracting embedded binary data perfectly as post-processing. Simulations using extracting embedded binary data as post-processing are presented to quantify some performance factors of concern. We confirmed that the proposed method could be of practical use.

Error Bounds for HDR Image Coding with JPEG XT

Abstract: ISO recently published a new image compression standard, JPEG XT, which extends the popular JPEG standard towards higher dynamic range, compression of alpha channels and lossless coding. In part 7 ofJPEG XT, a two-layer lossy image compression for HDR images isintroduced that reconstructs HDR signals by the combination of a baselayer following the legacy JPEG standard, and an extension layer thatenlarges the dynamic range to that of the original image. While bothbase and extension layer are entropy coded by the mechanisms specifiedin the legacy JPEG standard, only the base layer is visible to legacyJPEG decoders. The original JPEG standard now enforces in its part 2error bounds conforming implementations shall satisfy. The questionanswered in this article is in how far these error bounds carry overto error bounds of JPEG~XT for coding of HDR image signals.