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Title: Wavelet based images/video compression techniques for telemedicine application
Author: Ma, Jinming
Awarding Body: University of Buckingham
Current Institution: University of Buckingham
Date of Award: 2002
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The advent of multimedia computing has lead to an increased demand for digital images and videos (sequence of frames). Telemedicine is a major application of digital image processing and is increasingly deployed over different venues. However, there are still many challenges associated with this technology, especially on high quality real-time video compression. Wavelet transform has been becoming important in image compression applications because of its flexibility and efficiency in representing non-stationary signals. Generally, wavelet based compressions do not result in blocky effects and/or artifacts. However, existing wavelet-based compression systems are computationally intensive for real-time transmission of videos. In this thesis, we propose a novel region of interest (ROI) wavelet-based real-time video compression technique that is especially suited for telemedical applications. We shall demonstrate that with currently available and affordable hardware, the proposed ROI-based compression technique can simultaneously meet the stringent constraints imposed by the special requirements of telemedicine on processing time, bandwidth and high quality. The region of interest (e.g. the area of medical examination/surgery) in the decompressed images will have the highest possible image quality throughout the transmission at the expense of the unimportant outside region. Corresponding to the novel ROI-based wavelet transformation, suitable quantization and coding schemes are explored and incorporated into a complete video compression and transmission system. Factors that influence the ROI system performance with respect to computation time, compression ratio and video quality, are investigated with the aim of providing relevant suggestions on how to achieve desired performances. Software and user requirement factors include video frame size, the size of the ROI, the choice of wavelet filter, the scheme and depth of decomposition, and the quantization and coding schemes. Other performance influencing factors relate to the implementation platform, such as the local machine performance and network bandwidth. Comprehensive testing on the various software influencing factors and the CPU speed win be carried out to demonstrate the viability of the ROI system on currently available technology.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available