Fast compressed domain watermarking of MPEG multiplexed streams

In this paper, a new technique for watermarking of MPEG compressed video streams is proposed. The watermarking scheme operates directly in the domain of MPEG multiplexed streams. Perceptual models are used during the embedding process in order to preserve the quality of the video. The watermark is embedded in the compressed domain and is detected without the use of the original video sequence. Experimental evaluation demonstrates that the proposed scheme is able to withstand a variety of attacks. The resulting watermarking system is very fast and reliable, and is suitable for copyright protection and real-time content authentication applications

Fast watermarking of MPEG-1/2 streams using compressed-domain perceptual embedding and a generalized correlator detector

A novel technique is proposed for watermarking of MPEG-1 and MPEG-2 compressed video streams. The proposed scheme is applied directly in the domain of MPEG-1 system streams and MPEG-2 program streams (multiplexed streams). Perceptual models are used during the embedding process in order to avoid degradation of the video quality. The watermark is detected without the use of the original video sequence. A modified correlation-based detector is introduced that applies nonlinear preprocessing before correlation. Experimental evaluation demonstrates that the proposed scheme is able to withstand several common attacks. The resulting watermarking system is very fast and therefore suitable for copyright protection of compressed video

Optimized Transmission of JPEG2000 Streams Over Wireless Channels

The transmission of JPEG2000 images over wireless channels is examined using reorganization of the compressed images into error-resilient, product-coded streams. The product-code consists of Turbo-codes and Reed-Solomon codes which are optimized using an iterative process. The generation of the stream to be transmitted is performed directly using compressed JPEG2000 streams. The resulting scheme is tested for the transmission of compressed JPEG2000 images over wireless channels and is shown to outperform other algorithms which were recently proposed for the wireless transmission of images

Wireless Image Transmission Using Turbo Codes and Optimal Unequal Error Protection

A novel image transmission scheme is proposed for the communication of SPIHT image streams over wireless channels. The proposed scheme employs turbo codes and Reed-Solomon codes in order to deal effectively with burst errors. An algorithm for the optimal unequal error protection of the compressed bitstream is also proposed and applied in conjunction with an inherently more efficient technique for product code decoding. The resulting scheme is tested for the transmission of images over wireless channels. Experimental evaluation clearly demonstrates the superiority of the proposed transmission system in comparison to well-known robust coding schemes

Robust Image Transmission Based on Product-Code Optimization for Determinate State LDPC Decoding

We propose a novel scheme for error resilient image transmission. The proposed scheme employs a product coder consisting of LDPC codes and RS codes in order to deal effectively with bit errors. The efficiency of the proposed scheme is based on the exploitation of determinate symbols in Tanner graph decoding of LDPC codes and a novel product code optimization technique based on error estimation. Experimental evaluation demonstrates the superiority of the proposed system in comparison to recent state-of-the art techniques for image transmission

Product Code Optimization for Determinate State LDPC Decoding in Robust Image Transmission

We propose a novel scheme for error resilient image transmission. The proposed scheme employs a product coder consisting of LDPC codes and RS codes in order to deal effectively with bit errors. The efficiency of the proposed scheme is based on the exploitation of determinate symbols in Tanner graph decoding of LDPC codes and a novel product code optimization technique based on error estimation. Experimental evaluation demonstrates the superiority of the proposed system in comparison to recent state-of-the art techniques for image transmission

Transmission of Images over Noisy Channels Using Error-resilient Wavelet Coding and Forward Error Correction

A novel embedded wavelet coding scheme is proposed for the transmission of images over unreliable channels. The proposed scheme is based on the partitioning of information into a number of layers which can be decoded independently provided that some important and highly protected information is initially errorlessly transmitted to the decoder. Forward Error Correction is used in conjunction with the error-resilient source coder for the protection of the compressed stream. Unlike many other robust coding schemes presented to-date, the proposed scheme is able to decode portions of the bitstream even after the occurrence of uncorrectable errors. This coding strategy is very suitable for application with block coding schemes such as defined by the JPEG2000 standard. The proposed scheme is compared with other robust image coders and is shown to be very suitable for transmission of images over memoryless channels

Robust Transmission of H.264/AVC Video Using Adaptive Slice Grouping and Unequal Error Protection

We present a novel scheme for the transmission of H.264/AVC video streams over lossy packet networks. The proposed scheme exploits the error resilient features of H.264/AVC codec and employs Reed-Solomon codes to protect effectively the streams. The optimal classification of macroblocks into slice groups and the optimal channel rate allocation are achieved by iterating two interdependent steps. Simulations clearly demonstrate the superiority of the proposed method over other recent algorithms for transmission of H.264/AVC stream

Robust Transmission of H.264/AVC Streams Using Adaptive Group Slicing and Unequal Error Protection

We present a novel scheme for the transmission of H.264/AVC video streams over lossy packet networks. The proposed scheme exploits the error-resilient features of H.264/AVC codec and employs Reed-Solomon codes to protect effectively the streams. A novel technique for adaptive classification of macroblocks into three slice groups is also proposed. The optimal classification of macroblocks and the optimal channel rate allocation are achieved by iterating two interdependent steps. Dynamic programming techniques are used for the channel rate allocation process in order to reduce complexity. Simulations clearly demonstrate the superiority of the proposed method over other recent algorithms for transmission of H.264/AVC streams

Wavelet methods for the coding and transmission of images

In the present thesis, the coding and transmission of images is studied using wavelet methods. In particular, initially the coding of images using pyramidal methods is examined, which use nonlinear filters and achieve better overall performance in comparison to conventional pyramids. Additionally, new decompositions based on integer wavelets are proposed as well as methods for entropy coding which, in conjunction with the new decompositions, yield superior performance in comparison to other methods. Other issues are also examined such as the coding and protection of images for transmission over noisy channels and the reliable transmission of images and image sequences using Multiple Description Coding. Finally, the progressive transmission of stereoscopic images using wavelet methods is examined.Στην παρούσα διατριβή μελετώνται η κωδικοποίηση και μετάδοση εικόνων με χρήση μεθόδων κυματιδίων. Συγκεκριμένα, αρχικά εξετάζεται η κωδικοποίηση εικόνων με πυραμιδικές μεθόδους οι οποίες χρησιμοποιούν μη γραμμικά φίλτρα και οι οποίες επιτυγχάνουν γενικά καλύτερη επίδοση από τις συνηθισμένες πυραμίδες. Επιπρόσθετα προτείνονται νέες αποσυνθέσεις ακεραίων κυματιδίων καθώς και μέθοδοι κωδικοποίησης εντροπίας οι οποίες, σε συνδυασμό με τις νέες αποσυνθέσεις, δίνουν πολύ καλύτερα αποτελέσματα από άλλες μεθόδους. Εξετάζονται επίσης η κωδικοποίηση και η προστασία των εικόνων για μετάδοση σε ενθόρυβα κανάλια καθώς και η αξιόπιστη μετάδοση εικόνων και εικονοσειρών με χρήση Κωδικοποίησης Πολλαπλών Περιγραφών. Τέλος, μελετάται η προοδευτική μετάδοση στερεοσκοπικών εικόνων