Anew approach of reliable image and video transmission over noisy channels is proposed, For subband decomposed image and video, combined source coding and channel modulation design can achieve high compression efficie...
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Anew approach of reliable image and video transmission over noisy channels is proposed, For subband decomposed image and video, combined source coding and channel modulation design can achieve high compression efficiency and preferable quality. Further performance gain is obtained by multiresolution modulation as well as a bit-remapping scheme that assigns efficient mapping from each source codeword to channelmodulation points. We show that the combinedsourcecoding and modulation design outperforms conventional approaches, which design sourcecoding and modulation separately, A simple channel distortion approximation is derived by applying a bit-remapping scheme, which allows the power allocation to be employed to further enhance the performance. Compared to the joint source and channelcoding with a binary phase shift keying modulation system and fixed modulation with the one-to-one intelligent mapping system, the proposed system performs better in a middle-range signal-to-noise ratio and low channel bandwidth, The simulation is carried out on additive white Gaussian noise channels.
A newly derived algorithm called three-dimensional polynomial approximation coding (3DPAC) is being utilized in the applications of wireless video transmission. After combining the spatial and temporal domain, the vid...
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A newly derived algorithm called three-dimensional polynomial approximation coding (3DPAC) is being utilized in the applications of wireless video transmission. After combining the spatial and temporal domain, the video data is organized in a cube form, which has the features of processing parallelism and great compression ratio. Such a very low bit-rate video codec is able to support the wireless data transmission with a bit rate lower than 9.6 kbits/s, The system architecture will be presented and an experimental demonstration is also shown. For a video sequence of 176 x 144 frame size, PSNR up to 35 dB maybe obtained under 6.5 kbits/s transmission rate.
This paper presents a new parallel transmission framework for reliable multimedia data transmission over spectrally shaped channels using multicarrier modulation. We propose to transmit source data layers of different...
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This paper presents a new parallel transmission framework for reliable multimedia data transmission over spectrally shaped channels using multicarrier modulation. We propose to transmit source data layers of different perceptual importance in parallel, each occupying a number of subchannels. New loading algorithms are developed to efficiently allocate the available resources, e.g., transmitted power and bit rate, to the subchannels according to the source layers they transmit. Instead of making the bit error rate of all the subchannels equal as in most existing loading algorithms, the proposed algorithm assigns different error performance to the subchannels to achieve unequal error protection for different layers. The channel induced distortion in mean-square sense is minimized. We show that the proposed system can be applied nicely to both fixed length coding and variable-length coding. Asymptotic gains with respect to channel distortion are also derived. Numerical examples show that the proposed algorithm achieves significant performance improvement compared to the existing work, especially for spectrally shaped channels commonly used in in ADSL systems.
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