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Semantic segmentation-based semantic communication system for image transmission
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作者 Jiale Wu Celimuge Wu +4 位作者 Yangfei Lin Tsutomu Yoshinaga Lei Zhong Xianfu Chen Yusheng Ji 《Digital Communications and Networks》 SCIE CSCD 2024年第3期519-527,共9页
With the rapid development of artificial intelligence and the widespread use of the Internet of Things, semantic communication, as an emerging communication paradigm, has been attracting great interest. Taking image t... With the rapid development of artificial intelligence and the widespread use of the Internet of Things, semantic communication, as an emerging communication paradigm, has been attracting great interest. Taking image transmission as an example, from the semantic communication's view, not all pixels in the images are equally important for certain receivers. The existing semantic communication systems directly perform semantic encoding and decoding on the whole image, in which the region of interest cannot be identified. In this paper, we propose a novel semantic communication system for image transmission that can distinguish between Regions Of Interest (ROI) and Regions Of Non-Interest (RONI) based on semantic segmentation, where a semantic segmentation algorithm is used to classify each pixel of the image and distinguish ROI and RONI. The system also enables high-quality transmission of ROI with lower communication overheads by transmissions through different semantic communication networks with different bandwidth requirements. An improved metric θPSNR is proposed to evaluate the transmission accuracy of the novel semantic transmission network. Experimental results show that our proposed system achieves a significant performance improvement compared with existing approaches, namely, existing semantic communication approaches and the conventional approach without semantics. 展开更多
关键词 Semantic Communication Semantic segmentation image transmission image compression Deep learning
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A Hybrid Cybersecurity Algorithm for Digital Image Transmission over Advanced Communication Channel Models
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作者 Naglaa F.Soliman Fatma E.Fadl-Allah +3 位作者 Walid El-Shafai Mahmoud I.Aly Maali Alabdulhafith Fathi E.Abd El-Samie 《Computers, Materials & Continua》 SCIE EI 2024年第4期201-241,共41页
The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia technology.High-quality images require well-tuned communication ... The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia technology.High-quality images require well-tuned communication standards.The Single Carrier Frequency Division Multiple Access(SC-FDMA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power Ratio(PAPR).Data transmission through open-channel networks requires much concentration on security,reliability,and integrity.The data need a space away fromunauthorized access,modification,or deletion.These requirements are to be fulfilled by digital image watermarking and encryption.This paper ismainly concerned with secure image communication over the wireless SC-FDMA systemas an adopted communication standard.It introduces a robust image communication framework over SC-FDMA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver side.The proposed framework allows image watermarking based on the Discrete Cosine Transform(DCT)merged with the Singular Value Decomposition(SVD)in the so-called DCT-SVD watermarking.In addition,image encryption is implemented based on chaos and DNA encoding.The encrypted watermarked images are then transmitted through the wireless SC-FDMA system.The linearMinimumMean Square Error(MMSE)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted images.Two subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this paper.The study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude Modulation(QAM).Extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked images.In addition,different variants of SC-FDMA based on the Discrete Wavelet Transform(DWT),Discrete Cosine Transform(DCT),and Fast Fourier Transform(FFT)are considered and compared for the image communication task.The simulation results and comparison demonstrate clearly that DWT-SC-FDMAis better suited to the transmission of the digital images in the case of PedestrianAchannels,while the DCT-SC-FDMA is better suited to the transmission of the digital images in the case of Vehicular A channels. 展开更多
关键词 Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption
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A semantic segmentation-based underwater acoustic image transmission framework for cooperative SLAM
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作者 Jiaxu Li Guangyao Han +1 位作者 Shuai Chang Xiaomei Fu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期339-351,共13页
With the development of underwater sonar detection technology,simultaneous localization and mapping(SLAM)approach has attracted much attention in underwater navigation field in recent years.But the weak detection abil... With the development of underwater sonar detection technology,simultaneous localization and mapping(SLAM)approach has attracted much attention in underwater navigation field in recent years.But the weak detection ability of a single vehicle limits the SLAM performance in wide areas.Thereby,cooperative SLAM using multiple vehicles has become an important research direction.The key factor of cooperative SLAM is timely and efficient sonar image transmission among underwater vehicles.However,the limited bandwidth of underwater acoustic channels contradicts a large amount of sonar image data.It is essential to compress the images before transmission.Recently,deep neural networks have great value in image compression by virtue of the powerful learning ability of neural networks,but the existing sonar image compression methods based on neural network usually focus on the pixel-level information without the semantic-level information.In this paper,we propose a novel underwater acoustic transmission scheme called UAT-SSIC that includes semantic segmentation-based sonar image compression(SSIC)framework and the joint source-channel codec,to improve the accuracy of the semantic information of the reconstructed sonar image at the receiver.The SSIC framework consists of Auto-Encoder structure-based sonar image compression network,which is measured by a semantic segmentation network's residual.Considering that sonar images have the characteristics of blurred target edges,the semantic segmentation network used a special dilated convolution neural network(DiCNN)to enhance segmentation accuracy by expanding the range of receptive fields.The joint source-channel codec with unequal error protection is proposed that adjusts the power level of the transmitted data,which deal with sonar image transmission error caused by the serious underwater acoustic channel.Experiment results demonstrate that our method preserves more semantic information,with advantages over existing methods at the same compression ratio.It also improves the error tolerance and packet loss resistance of transmission. 展开更多
关键词 Semantic segmentation Sonar image transmission Learning-based compression
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Improving the Transmission Security of Vein Images Using a Bezier Curve and Long Short-Term Memory
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作者 Ahmed H.Alhadethi Ikram Smaoui +1 位作者 Ahmed Fakhfakh Saad M.Darwish 《Computers, Materials & Continua》 SCIE EI 2024年第6期4825-4844,共20页
The act of transmitting photos via the Internet has become a routine and significant activity.Enhancing the security measures to safeguard these images from counterfeiting and modifications is a critical domain that c... The act of transmitting photos via the Internet has become a routine and significant activity.Enhancing the security measures to safeguard these images from counterfeiting and modifications is a critical domain that can still be further enhanced.This study presents a system that employs a range of approaches and algorithms to ensure the security of transmitted venous images.The main goal of this work is to create a very effective system for compressing individual biometrics in order to improve the overall accuracy and security of digital photographs by means of image compression.This paper introduces a content-based image authentication mechanism that is suitable for usage across an untrusted network and resistant to data loss during transmission.By employing scale attributes and a key-dependent parametric Long Short-Term Memory(LSTM),it is feasible to improve the resilience of digital signatures against image deterioration and strengthen their security against malicious actions.Furthermore,the successful implementation of transmitting biometric data in a compressed format over a wireless network has been accomplished.For applications involving the transmission and sharing of images across a network.The suggested technique utilizes the scalability of a structural digital signature to attain a satisfactory equilibrium between security and picture transfer.An effective adaptive compression strategy was created to lengthen the overall lifetime of the network by sharing the processing of responsibilities.This scheme ensures a large reduction in computational and energy requirements while minimizing image quality loss.This approach employs multi-scale characteristics to improve the resistance of signatures against image deterioration.The proposed system attained a Gaussian noise value of 98%and a rotation accuracy surpassing 99%. 展开更多
关键词 image transmission image compression text hiding Bezier curve Histogram of Oriented Gradients(HOG) LSTM image enhancement Gaussian noise ROTATION
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Robust transmission of progressive image bitstreams based on DCT over broadband wireless channels 被引量:1
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作者 王东华 周源华 马曾栋 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第2期219-225,共7页
A robust progressive image transmission scheme over broadband wireless fading channels is developed for 4th generation wireless communication systems (4G) in this paper. The proposed scheme is based on space-time bl... A robust progressive image transmission scheme over broadband wireless fading channels is developed for 4th generation wireless communication systems (4G) in this paper. The proposed scheme is based on space-time block coded orthogonal frequency-division multiplexing (OFDM) with 4 transmit antennas and 2 receive antennas and uses a simplified minimum mean square error (MMSE) detector instead of maximum likelihood (ML) detectors. Considering DCT is simpler and more widely applied in the industry than wavelet transforms, a progressive image compression method based on DCT called mean-subtract embedded DCT (MSEDCT) is developed, with a simple mean-subtract method for the redundancy of reorganized DC blocks in addition to a structure similar to the embedded zerotree wavelet coding (EZW) method. Then after analyzing and testing bit importance of the progressive MSEDCT bitstreams, the layered unequal error protection method of joint source-channels coding based on Reed-Solomon (RS) codes is used to protect different parts of bitstreams, providing different QoS assurances and good flexibility. Simulation experiments show our proposed scheme can effectively degrade fading effects and obtain better image transmission effects with 10 -20 dB average peak-sig- nal-noise-ratio (PSNR) gains at the median Eb/No than those schemes without space-time coded OFDM or equal error protections with space-time coded OFDM. 展开更多
关键词 broadband communication embedded source coding image transmission joint source-channel coding
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Irregular and regular LDPC codes with high spectrum efficiency modulation in image transmission over fading channel 被引量:1
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作者 MaPiming YuanDongfeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第1期26-30,共5页
If the degree distribution is chosen carefully, the irregular low-density parity-check (LDPC) codes can outperform the regular ones. An image transmission system is proposed by combining regular and irregular LDPC cod... If the degree distribution is chosen carefully, the irregular low-density parity-check (LDPC) codes can outperform the regular ones. An image transmission system is proposed by combining regular and irregular LDPC codes with 16QAM/64QAM modulation to improve both efficiency and reliability. Simulaton results show that LDPC codes are good coding schemes over fading channel in image communication with lower system complexity. More over, irregular codes can obtain a code gain of about 0.7 dB compared with regular ones when BER is 10 -4. So the irregular LDPC codes are more suitable for image transmission than the regular codes. 展开更多
关键词 irregular low-density parity-check (LDPC) codes degree distribution image transmission high spectrum efficiency modulation.
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EFFICIENT IMAGE TRANSMISSION SCHEME IN FMT SYSTEM 被引量:1
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作者 QiZhongrui GaoZhenming 《Journal of Electronics(China)》 2005年第2期190-196,共7页
An efficient image transmission scheme is proposed based on byte partition and adaptive sub-channel distribution technique in Filtered MultiTone (FMT) system over frequency selective slow fading channel. According to ... An efficient image transmission scheme is proposed based on byte partition and adaptive sub-channel distribution technique in Filtered MultiTone (FMT) system over frequency selective slow fading channel. According to the simulation results and analysis of a typical image with matlab, improvement in Peak Signal to Noise Ratio (PSNR) of the received image and low complexity for equalization is demonstrated remarkably. Comparing with no adaptive and no actual channel equalization scheme, the proposed scheme saves over 6 dB when PSNR=40 dB. 展开更多
关键词 image transmission Filtered MultiTone (FMT) Peak Signal to Noise Ratio (PSNR)
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Gradient based restoration of coal mine images obtained by underground wireless transmissions 被引量:2
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作者 Lu Zhaolin Qian Jiansheng Li Leida 《Mining Science and Technology》 EI CAS 2011年第6期809-813,共5页
Curvature-driven diffusion (CDD) principles were used to develop a novel gradient based image restora- tion algorithm. The algorithm fills in blocks of missing data in a wireless image after transmission through the n... Curvature-driven diffusion (CDD) principles were used to develop a novel gradient based image restora- tion algorithm. The algorithm fills in blocks of missing data in a wireless image after transmission through the network. When images are transmitted over fading channels, especially in the severe circum- stances of a coal mine, blocks of the image may be destroyed by the effects of noise. Instead of using com- mon retransmission query protocols the lost data is reconstructed by using the adaptive curvature-driven diffusion (ACDD) image restoration algorithm in the gradient domain of the destroyed image. Missing blocks are restored by the method in two steps: In step one, the missing blocks are filled in the gradient domain by the ACDD algorithm; in step two, and the image is reconstructed from the reformed gradients by solving a Poisson equation. The proposed method eliminates the staircase effect and accelerates the convergence rate. This is demonstrated by experimental results. 展开更多
关键词 image restoration Curvature-driven diffusion Gradient domain Wireless image transmission Poisson equation
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Information loss recovery for JPEG2000 image transmission in an error-prone environment
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作者 刘洁瑜 张德运 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第3期430-435,共6页
Information loss recovery techniques are important for transmitting images over error-prone channels at the decoder. A novel error recovery scheme for JPEG2000 image is presented in this paper, which adopts different ... Information loss recovery techniques are important for transmitting images over error-prone channels at the decoder. A novel error recovery scheme for JPEG2000 image is presented in this paper, which adopts different techniques for the lowest frequency coefficients and high frequency coefficients in the wavelet domain. The low-frequency recovery algorithm was implemented by adopting the watermarking technique and the packet structure of JPEG2000. The low-frequency eoefficients taken as the hidden data were extracted from the compressed bit stream, and then were embedded back into the bit stream itself prior to transmission. The embedded data were used to recover the information loss. High-frequency reconstruction was performed in bitplane base. The damaged bitplanes were recovered according to the correlation in the wavelet subband structure and by using the algorithm based on the horizontal and vertical edge detection. Experiments verified the effectiveness of these algorithms. 展开更多
关键词 JPEG2000 error recovery image transmission bitplane
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DESIGN OF MODULATION AND COMPRESSION CODING IN UNDERWATER ACOUSTIC IMAGE TRANSMISSION
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作者 程恩 余丽敏 林耿超 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第3期202-207,共6页
This paper describes the design of modulation, compression coding and transmission control in underwater acoustic color image transmission system. This design adapts a special system of modulation and transmission con... This paper describes the design of modulation, compression coding and transmission control in underwater acoustic color image transmission system. This design adapts a special system of modulation and transmission control based on a DSP(Digital Signal Processing) chip, to cope with the complex underwater acoustic channel. The hardware block diagram and software flow chart are presented. 展开更多
关键词 underwater image transmission MFSK (Multiple Frequency Shifting Keying) RLE (Route Length Encode) DSP
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A simple and efficient method for image transmission over inferior channel
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作者 周霆 许明 +1 位作者 陈东侠 余轮 《Journal of Shanghai University(English Edition)》 CAS 2008年第2期141-145,共5页
The constrained Viterbi algorithm (C-VA) makes use of some prior reliable information to reduce complexity and improve performance of Viterbi algorithm (VA). However it can only be used in the concatenate code sch... The constrained Viterbi algorithm (C-VA) makes use of some prior reliable information to reduce complexity and improve performance of Viterbi algorithm (VA). However it can only be used in the concatenate code scheme because the detection result of cyclic redundancy check code (CRC) is exploited to provide reliable information. In this paper, a different way is proposed to provide reliable information for C-VA, which is possible to be used in simple codec. Known bits were added to the set partitioning in hierarchical trees (SPIHT) coded image sequence periodically and directly. They were thought to be reliable information for C-VA in the decoder. Experimental results show that the proposed scheme can obtain much better error resilient ability compared with conventional VA under the extremely inferior channel condition if the best desired quality of reconstructed images can be sacrificed. 展开更多
关键词 constrained Viterbi algorithm (C-VA) known bits set partitioning in hierarchical trees (SPIHT) image transmission.
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Underwater Acoustic Image Transmission System Based on DSF
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作者 程恩 许茹 《Marine Science Bulletin》 2002年第1期27-33,共7页
The underwater acoustic image transmission system based on the high-speed DSP device TMS320C549 has been studied.We use Goertzel algorithm for source decoding and MFSK for modulation.Turbo code is used for channel cod... The underwater acoustic image transmission system based on the high-speed DSP device TMS320C549 has been studied.We use Goertzel algorithm for source decoding and MFSK for modulation.Turbo code is used for channel coding and decoding.The purpose is to implement underwater video image data transmission. 展开更多
关键词 underwater image transmission MFSK Goertzel algorithm Turbo code
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DESIGN OF IRREGULAR LDPC CODE WITH UNEQUAL ERROR PROTECTION PROPERTY AND ITS PERFORMANCE ANALYSIS ON IMAGE TRANSMISSION
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作者 Wang Ruihua Yin Liuguo +1 位作者 Yu Quan Lu Jianhua 《Journal of Electronics(China)》 2005年第6期658-662,共5页
Based on the property that high degree variable nodes within an irregular LowDensity Parity-Check (LDPC) code have more powerful error-correcting capability than that of low degree variable nodes, a group of irregular... Based on the property that high degree variable nodes within an irregular LowDensity Parity-Check (LDPC) code have more powerful error-correcting capability than that of low degree variable nodes, a group of irregular LDPC codes with Unequal Error Protection (UEP)property is designed in this letter. Simulation results show that the transmission quality of the image may be effectively improved with this class of irregular LDPC code. 展开更多
关键词 Irregular Low-Density Parity-Check (LDPC) code Unequal Error Protection (UEP) image transmission
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Deep-Learning-Empowered 3D Reconstruction for Dehazed Images in IoT-Enhanced Smart Cities 被引量:2
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作者 Jing Zhang Xin Qi +1 位作者 San Hlaing Myint Zheng Wen 《Computers, Materials & Continua》 SCIE EI 2021年第8期2807-2824,共18页
With increasingly more smart cameras deployed in infrastructure and commercial buildings,3D reconstruction can quickly obtain cities’information and improve the efficiency of government services.Images collected in o... With increasingly more smart cameras deployed in infrastructure and commercial buildings,3D reconstruction can quickly obtain cities’information and improve the efficiency of government services.Images collected in outdoor hazy environments are prone to color distortion and low contrast;thus,the desired visual effect cannot be achieved and the difficulty of target detection is increased.Artificial intelligence(AI)solutions provide great help for dehazy images,which can automatically identify patterns or monitor the environment.Therefore,we propose a 3D reconstruction method of dehazed images for smart cities based on deep learning.First,we propose a fine transmission image deep convolutional regression network(FT-DCRN)dehazing algorithm that uses fine transmission image and atmospheric light value to compute dehazed image.The DCRN is used to obtain the coarse transmission image,which can not only expand the receptive field of the network but also retain the features to maintain the nonlinearity of the overall network.The fine transmission image is obtained by refining the coarse transmission image using a guided filter.The atmospheric light value is estimated according to the position and brightness of the pixels in the original hazy image.Second,we use the dehazed images generated by the FT-DCRN dehazing algorithm for 3D reconstruction.An advanced relaxed iterative fine matching based on the structure from motion(ARI-SFM)algorithm is proposed.The ARISFM algorithm,which obtains the fine matching corner pairs and reduces the number of iterations,establishes an accurate one-to-one matching corner relationship.The experimental results show that our FT-DCRN dehazing algorithm improves the accuracy compared to other representative algorithms.In addition,the ARI-SFM algorithm guarantees the precision and improves the efficiency. 展开更多
关键词 3D reconstruction dehazed image deep learning fine transmission image structure from motion algorithm
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Seeing at a distance with multicore fibers
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作者 Haogong Feng Xi Chen +4 位作者 Runze Zhu Yifeng Xiong Ye Chen Yanqing Lu Fei Xu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第7期39-49,共11页
Images and videos provide a wealth of information for people in production and life.Although most digital information is transmitted via optical fiber,the image acquisition and transmission processes still rely heavil... Images and videos provide a wealth of information for people in production and life.Although most digital information is transmitted via optical fiber,the image acquisition and transmission processes still rely heavily on electronic circuits.The development of all-optical transmission networks and optical computing frameworks has pointed to the direction for the next generation of data transmission and information processing.Here,we propose a high-speed,low-cost,multiplexed parallel and one-piece all-fiber architecture for image acquisition,encoding,and transmission,called the Multicore Fiber Acquisition and Transmission Image System(MFAT).Based on different spatial and modal channels of the multicore fiber,fiber-coupled self-encoding,and digital aperture decoding technology,scenes can be observed directly from up to 1 km away.The expansion of capacity provides the possibility of parallel coded transmission of multimodal high-quality data.MFAT requires no additional signal transmitting and receiving equipment.The all-fiber processing saves the time traditionally spent on signal conversion and image pre-processing(compression,encoding,and modulation).Additionally,it provides an effective solution for 2D information acquisition and transmission tasks in extreme environments such as high temperatures and electromagnetic interference. 展开更多
关键词 long-distance fiber imaging image transmission parallel transmission all-optical encoding multicore fiber
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SNR-adaptive deep joint source-channel coding scheme for image semantic transmission with convolutional block attention module
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作者 Yang Yujia Liu Yiming +1 位作者 Zhang Wenjia Zhang Zhi 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2024年第1期1-11,共11页
With the development of deep learning(DL),joint source-channel coding(JSCC)solutions for end-to-end transmission have gained a lot of attention.Adaptive deep JSCC schemes support dynamically adjusting the rate accordi... With the development of deep learning(DL),joint source-channel coding(JSCC)solutions for end-to-end transmission have gained a lot of attention.Adaptive deep JSCC schemes support dynamically adjusting the rate according to different channel conditions during transmission,enhancing robustness in dynamic wireless environment.However,most of the existing adaptive JSCC schemes only consider different channel conditions,ignoring the different feature importance in the image processing and transmission.The uniform compression of different features in the image may result in the compromise of critical image details,particularly in low signal-to-noise ratio(SNR)scenarios.To address the above issues,in this paper,a dual attention mechanism is introduced and an SNR-adaptive deep JSCC mechanism with a convolutional block attention module(CBAM)is proposed,in which matrix operations are applied to features in spatial and channel dimensions respectively.The proposed solution concatenates the pooling feature with the SNR level and passes it sequentially through the channel attention network and spatial attention network to obtain the importance evaluation result.Experiments show that the proposed solution outperforms other baseline schemes in terms of peak SNR(PSNR)and structural similarity(SSIM),particularly in low SNR scenarios or when dealing with complex image content. 展开更多
关键词 semantic communication joint source-channel coding image transmission
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Secret Image Communication Scheme Based on Visual Cryptography and Tetrolet Tiling Patterns
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作者 N.RajeshKumar DYuvaraj +3 位作者 G.Manikandan R.BalaKrishnan B.Karthikeyan D.Narasimhanand N.R.Raajan 《Computers, Materials & Continua》 SCIE EI 2020年第11期1283-1301,共19页
Visual cryptographic scheme is specially designed for secret image sharing in the form of shadow images.The basic idea of visual cryptography is to construct two or more secret shares from the original image in the fo... Visual cryptographic scheme is specially designed for secret image sharing in the form of shadow images.The basic idea of visual cryptography is to construct two or more secret shares from the original image in the form of chaotic image.In this paper,a novel secret image communication scheme based on visual cryptography and Tetrolet tiling patterns is proposed.The proposed image communication scheme will break the secret image into more shadow images based on the Tetrolet tiling patterns.The secret image is divided into 4×4 blocks of tetrominoes and employs the concept of visual cryptography to hide the secret image.The main feature of the proposed scheme is the selection of random blocks to apply the tetrolet tilling patterns from the fundamental tetrolet pattern board.Single procedure is used to perform both tetrolet transform and the scheme of visual cryptography.Finally,the experimental results showcase the proposed scheme is an extraordinary approach to transfer the secret image and reconstruct the secret image with high visual quality in the receiver end. 展开更多
关键词 Tetrominoes tile visual secret share image transmission security visual cryptography
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Digital Solution to Mining Image Monitor System
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作者 刘越男 孙继平 +1 位作者 苏辉 那景芳 《Journal of China University of Mining and Technology》 2001年第2期204-207,共4页
The thesis describes an advanced digital solution to mining digital image monitor system, which makes up the shortage of the traditional mining analog image monitor. It illustrates the system components and how to cho... The thesis describes an advanced digital solution to mining digital image monitor system, which makes up the shortage of the traditional mining analog image monitor. It illustrates the system components and how to choose the encoder bandwidth of the system. The problem of image multicast and its solution in LAN are also discussed. 展开更多
关键词 mining monitor image transmission LAN
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Full Image Inference Conditionally upon Available Pieces Transmitted into Limited Resources Context
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作者 Rodrigue Saoungoumi-Sourpele Jean Michel Nlong +2 位作者 David Jaurès Fotsa-Mbogne Jean-Robert Kala Kamdjoug Laurent Bitjoka 《Journal of Signal and Information Processing》 2021年第3期57-69,共13页
<span style="font-family:Verdana;">In a context marked by the proliferation of smartphones and multimedia applications, the processing and transmission of images </span><span style="font-... <span style="font-family:Verdana;">In a context marked by the proliferation of smartphones and multimedia applications, the processing and transmission of images </span><span style="font-family:Verdana;">ha</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">ve</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> become a real problem. Image compression </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">is</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> the first approach to address this problem, it nevertheless suffers from its inability to adapt to the dynamics of limited environments, consisting mainly of mobile equipment and wireless networks. In this work, we propose a stochastic model to gradually estimate an image upon </span><span style="font-family:Verdana;">information</span><span style="font-family:Verdana;"> on its pixels that are transmitted progressively. We consider this transmission as a </span><span style="font-family:Verdana;">dynamical</span><span style="font-family:Verdana;"> process, where the sender </span><span style="font-family:Verdana;">push</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">es</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> the data in decreasing significance order. In order to adapt to network conditions and performances, instead of truncating the pixels, we suggest a new method called Fast Reconstruction Method by Kalman Filtering (FRM-KF) consisting </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">of</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> recursive inference of the not yet received layers belonging to a sequence of bitplanes. After empirical analysis, we estimate </span><span style="font-family:Verdana;">parameters</span><span style="font-family:Verdana;"> of our model which is a linear discrete Kalman Filter. We assume the initial law of information to be the uniform distribution on the set [0, 255] corresponding to the range of gray levels. The performances of FRM-KF method ha</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">ve </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">been evaluated in terms of the ratios in the quality of data image/size sent and in the quality of image/time required for treatment. </span><span style="font-family:Verdana;">A high</span><span style="font-family:Verdana;"> quality was reached faster with relatively small data (less than 10% of image data is needed to obtain up to the sixth-quality image). The time for treatment also decreases faster with </span><span style="font-family:Verdana;">number</span><span style="font-family:Verdana;"> of received layers. However, we found that the time of image treatment might be large starting from </span><span style="font-family:Verdana;">a image</span><span style="font-family:Verdana;"> resolution of 1024 * 1024. Hence, we recommend </span><span style="font-family:Verdana;">FRM-KF</span><span style="font-family:Verdana;"> method for resolutions less or equal to 512 * 512. A statistical comparative analysis reveals that FRM-KF is competitive and suitable to be implemented </span><span style="font-family:Verdana;">on</span><span style="font-family:Verdana;"> limited </span><span style="font-family:Verdana;">resource</span><span style="font-family:Verdana;"> environments.</span></span></span></span> 展开更多
关键词 Progressive image transmission Bitplane Coding Kalman Filtering Fast Reconstruction
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Transmissive multifocal laser speckle contrast imaging through thick tissue
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作者 Ruoyu Chen Peng Miao Shanbao Tong 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2023年第5期129-138,共10页
Laser speckle contrast imaging(LSCI)is a powerful tool for monitoring blood flow changes in tissue or vessels in vivo,but its applications are limited by shallow penetration depth under reflective imaging configuratio... Laser speckle contrast imaging(LSCI)is a powerful tool for monitoring blood flow changes in tissue or vessels in vivo,but its applications are limited by shallow penetration depth under reflective imaging configuration.The traditional LSCI setup has been used in transmissive imaging for depth extension up to 2l_(t)–3l_(t)(l_(t)is the transport mean free path),but the blood flow estimation is biased due to the depth uncertainty in large depth of field(DOF)images.In this study,we propose a transmissive multifocal LSCI for depth-resolved blood flow in thick tissue,further extending the transmissive LSCI for tissue thickness up to 12lt.The limited-DOF imaging system is applied to the multifocal acquisition,and the depth of the vessel is estimated using a robust visibility parameter V_(r)in the coherent domain.The accuracy and linearity of depth estimation are tested by Monte Carlo simulations.Based on the proposed method,the model of contrast analysis resolving the depth information is established and verified in a phantom experiment.We demonstrated its effectiveness in acquiring depth-resolved vessel structures and flow dynamics in in vivo imaging of chick embryos. 展开更多
关键词 Transmissive imaging multifocal imaging DEPTH laser speckle contrast model.
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