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1

An efficient approach for optimization of the parameters In transmission system applied In DWT+SPIHT using whale algorithm (WA)

Mourad Larbi, Mustapha Khelifi, Mohamed Rida Lahcene

Przegląd Elektrotechniczny

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2022

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R. 98, nr 11

71--78

EN

The compression of image using analyzing techniques give us q high quality in the reconstructed image however in the case of transmission produce a sensitive (to the channel noise) image .In this paper we are going to use combination between error detection , source and channel coding with unequal distribution in the code rate our approach shows a high efficiency and optimization in the use of the code rate using Whale Algorithm (WA) (minimization in the redundant bits) compared to other approaches. The results of the work carried out in this article are mainly focused on the medical images compression by the (DWT+SPIHT) method, which, in fact, allow a significant reduction for data. We are also interested in the transmission of these images on an channel in a way that can provide a high bit rate with good transmission quality, by exploiting the channel coding technique, which is effective in combating the noise introduced during the transmission of these images.

PL

Kompresja obrazu przy użyciu technik analitycznych daje nam q wysoką jakość rekonstruowanego obrazu, jednak w przypadku transmisji wytwarzamy obraz wrażliwy (na szum kanału). przy nierównym rozkładzie współczynnika kodowania nasze podejście wykazuje wysoką wydajność i optymalizację w wykorzystaniu współczynnika kodowania przy użyciu algorytmu wieloryba (WA) (minimalizacja w nadmiarowych bitach) w porównaniu z innymi podejściami. Wyniki prac przeprowadzonych w niniejszym artykule koncentrują się głównie na kompresji obrazów medycznych metodą (DWT+SPIHT), która w rzeczywistości pozwala na znaczną redukcję danych. Interesuje nas również transmisja tych obrazów na kanale w sposób, który może zapewnić wysoką przepływność przy dobrej jakości transmisji, wykorzystując technikę kodowania kanałów, która skutecznie zwalcza szumy wprowadzane podczas transmisji tych obrazów.

2

An Improved Downlink MC-CDMA System for Effcient Image Transmission

Bendelhoum M. S., Djebbari A., Boukli-Hacene I., Taleb-Ahmed A.

Journal of Telecommunications and Information Technology

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2017

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nr 4

5--16

EN

Image compression is an essential stage of the data archiving and transmitting process, as it reduces the number of bits and the time required to complete the transmission. In this article, a study of image transmission over the Multi-Carrier Code Division Multiple Access (MC-CDMA) downlink system is presented. The solution proposed relies on source coding combined with channel coding. The Discrete Wavelet Transform (DWT) method is used in conjunction with the SPIHT coder to compress the image, then the data generated is transmitted with the MC-CDMA technique over a noisy channel. The results show that image transmissions performed over MC-CDMA using the SPIHT model are better than the traditional approach like MC-CDMA in the AWGN channel.

3

Tree Structure Based Data Hiding for Progressive Transmission Images

Tsai P.

Fundamenta Informaticae

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2010

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Vol. 98, nr 2/3

257-275

EN

Progressive image transmission (PIT) is supported by several encoders such as SPIHT, JPEG2000 and so on. However, few of data hiding scheme for progressive transmission images is designed. In this paper, tree-structure-based data hiding for set partitioning in hierarchical trees (SPIHT) images is proposed. The bit stream of SPIHT multi-stage encoded was structured of tree. The secret image can be progressively embedded into SPIHT bit trees. Experimental results showed the progressive image data hiding is achieved. The secret image is progressively embedded/extracted in SPIHT encoded images. Furthermore, a higher hiding capacity was provided in an earlier encoding which helped the secret image to be identified earlier. Also, an adaptive hiding capacity could be developed by using different tree structures. In comparison with Tsai et al.'s scheme, the proposed scheme had a higher hiding capacity and a better secret image quality.

4

Context based multiwavelet Image coding using SPIHT framework

He X. C., Yu S. S., Zhou J. L., Li J.

Machine Graphics and Vision

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2003

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Vol. 12, No. 3

363-376

EN

In this paper, multiwavelets are considered in the context of image compression. For evaluating the effectiveness of multiwavelet transform for coding image at low bit-rates, an efficient embedded coding of wavelet coefficients has been realized. Firstly, selecting the BSA(4/4)* filters, two-dimensional (2-D) image is transformed with our proposed algorithm I. Secondly; we split the coefficients into two parts, namely the significance map and the residue map. Then a new modified algorithm for set partitioning in hierarchical trees (SPIHT) is proposed prencoding the significance map. Further, algorithm III is presented for coding the residue map. Finally, we adopt context-based adaptive arithmetic coding to encode the bit stream. We also provide some experimental results proving that multiwavelets are worth studying, and compare them with those of other multiwavelet and scalar wavelet algorithm.

5

Fully spatial and SNR scalable, SPIHT-based image coding for transmission over heterogenous networks

Danyali H., Mertins A.

Journal of Telecommunications and Information Technology

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2003

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nr 2

92-98

EN

This paper presents a fully scalable image coding scheme based on the set partitioning in hierarchical trees (SPIHT) algorithm. The proposed algorithm, called fully scalable SPIHT (FS-SPIHT), adds the spatial scalability feature to the SPIHT algorithm. It provides this new functionality without sacrificing other important features of the original SPIHT bitstream such as: compression efficiency, full embeddedness and rate scalability. The flexible output bitstream of the FS-SPIHT encoder which consists of a set of embedded parts related to different resolutions and quality levels can be easily adapted (reordered) to given bandwidth and resolution requirements by a simple parser without decoding the bitstream. FS-SPIHT is a very good candidate for image communication over heterogenous networks which requires high degree of scalability from image coding systems.