Modified distribution of correlation noise for improved Wyner-Ziv video coding performance

This research work was partially funded by the Strategic Educational Pathways Scholarship Scheme (STEPS-Malta) and by European Union - European Social Fund (ESF 1.25).Despite theorems predicting that Distributed Video Coding can achieve the same performance as traditional predictive video coding schemes, the coding efficiency of practical architectures is still far from these bounds. This is attributed to the poor Side Information (SI) estimated at the decoder and to the inability of the channel codes to recover the source at the Slepian-Wolf (SW) limits. This paper tackles the latter issue by recovering the SI bit-planes starting from the most unreliable bit of each coefficient. Most of the mismatch in SI is thus accumulated within the first decoded bit-planes, leaving the last bit-planes with very few or no mismatch. Low-Density Parity-Check Accumulate (LDPCA) codes can then benefit from such compact distribution of correlation noise since they offer a smaller percentage error, from the SW bounds, when mismatch is accumulated in few higher entropy bit-planes. Furthermore, with this setup, most of the last bit-planes can be recovered very effectively using just 8-bit or 16-bit Cyclic Redundancy Codes. Experimental results show that the proposed scheme can reduce the Wyner-Ziv bit-rates by up to 21% compared to the DISCOVER codec.peer-reviewe

Multimedia signal processing

Diplomová práce se zabývá vytvořením vhodných multimediálních podkladů z oblasti signálů a soustav se spojitým časem. Pochopení této problematiky je velmi důležité, neboť povinný předmět Signály a soustavy, resp. BSIS, je vyučován na bakalářském stupni oboru EST. Porozumění vyučované látky je nezbytnou prerekvizitou v dalších předmětech k úspěšnému zvládnutí navazující látky. Další část diplomové práce je zaměřena na jednorozměrné diskrétní signály. Konkrétně si klade za cíl realizaci softwarového systému. Navržený systém disponuje jak základními operacemi (energie signálu, počet průchodů nulou atd.) se zvukovými soubory, tak i funkcemi složitějšími, mezi které se řadí např. vyhledávání samohlásek v plynulé řeči. Systém je rozdělen na dvě části. První program analyzuje právě zvukové soubory, vytváří nový zvukový soubor s hledanou samohláskou a soubory s potřebnými parametry pro další zpracování. Druhý program analyzuje získaná data, která následně statisticky vyhodnocuje. Výsledný systém může být užitečný pro identifikaci mluvčího, jeho emočního stavu atd.The aim of this thesis is creation the appropriate multimedia support for signals and system with continuous time. The understanding of this issue is very important, because the obligatory subject Signals and systems, exactly BSIS, is taught at the EST bachelor degree. The understanding is also necessary prerequisite to successful understanding next topics in other related subjects. The next part of this thesis is focused on one dimension discrete signals. Concretely, the aim of this part is a realization of software system. Designed system has some basic operations (the signal energy, the number of signal zero crossing etc.) with sound files and also some advance functions e.g. vowel seeking and separating in fluent speech. The system is divided into two main parts. The first one analyzes sound files, creates the new sound file with wanted vowel and matrices with important parameters for other processing. The second program computes with given data, which statistically evaluates in other steps. The final system can be useful for speaker recognition, his emotional status etc.

Improving MPEG-4 coding performance by jointly optimising compression and blocking effect elimination

Centre for Multimedia Signal Processing, Department of Electronic and Information EngineeringAccepted ManuscriptPublishe

A fast two-stage algorithm for realizing matching pursuit

Centre for Multimedia Signal Processing, Department of Electronic and Information EngineeringVersion of RecordPublishe

Macroblock-based algorithm for dual-bitstream MPEG video streaming with VCR functionalities

Centre for Multimedia Signal Processing, Department of Electronic and Information EngineeringVersion of RecordPublishe

A feature-assisted search strategy for block motion estimation

Centre for Multimedia Signal Processing, Department of Electronic and Information EngineeringVersion of RecordPublishe

Watermark extraction by magnifying noise and applying global minimum decoder

Author name used in this publication: David ZhangCenter for Multimedia Signal Processing and Department of ComputingVersion of RecordPublishe