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Application of Narration in QR Code Image Design
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作者 Kaixin Yao 《Journal of Contemporary Educational Research》 2022年第10期62-67,共6页
Narrative design was originated in the 20th century.As a kind of design thinking,it runs through various fields such as architecture,environment,and new media.The QR code design has gradually become a bridge for media... Narrative design was originated in the 20th century.As a kind of design thinking,it runs through various fields such as architecture,environment,and new media.The QR code design has gradually become a bridge for media integration design,and its importance is becoming increasingly obvious.An optimized QR code design may gradually replace the original LOGO of certain goods or brand.In this study,narration is embedded into the QR code design,and a new QR code design image is gradually constructed through three ways of planarization,spatialization,and narration. 展开更多
关键词 NARRATION QR code image Design optimization
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VLSI Implementation of a Wavelet Image Coder
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作者 乔世杰 王国裕 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第7期695-700,共6页
A modular architecture for two dimension (2 D) discrete wavelet transform (DWT) is designed.The image data can be wavelet transformed in real time,and the structure can be easily scaled up to higher levels of DWT.A f... A modular architecture for two dimension (2 D) discrete wavelet transform (DWT) is designed.The image data can be wavelet transformed in real time,and the structure can be easily scaled up to higher levels of DWT.A fast zerotree image coding (FZIC) algorithm is proposed by using a simple sequential scan order and two flag maps.The VLSI structure for FZIC is then presented.By combining 2 D DWT and FZIC,a wavelet image coder is finally designed.The coder is programmed,simulated,synthesized,and successfully verified by ALTERA CPLD. 展开更多
关键词 discrete wavelet transform zerotree image coding VLSI Verilog HDL CPLD
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AUTOMATED IMAGE MATCHING WITH CODED POINTS IN STEREOVISION MEASUREMENT 被引量:1
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作者 Dong Mingli Zhou Xiaogang +2 位作者 Zhu Lianqing LU Naiguang Sun Yunan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期453-456,共4页
A coding-based method to solve the image matching problems in stereovision measurement is presented. The solution is to add and append an identity ID to the retro-reflect point, so it can be identified efficiently und... A coding-based method to solve the image matching problems in stereovision measurement is presented. The solution is to add and append an identity ID to the retro-reflect point, so it can be identified efficiently under the complicated circumstances and has the characteristics of rotation, zooming, and deformation independence. Its design architecture and implementation process in details based on the theory of stereovision measurement are described. The method is effective on reducing processing data time, improving accuracy of image matching and automation of measuring system through experiments. 展开更多
关键词 coded point image matching Stereovision measurement
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Elimination of the Background Noise of the Decoded Image in Fresnel Zone Plate Scanning Holography
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作者 孙萍 谢敬辉 《Journal of Beijing Institute of Technology》 EI CAS 2005年第3期225-228,共4页
A method of digitally high pass filtering in frequency domain is proposed to eliminate the background noise of the decoded image in Fresnel zone plate scanning holography. The high pass filter is designed as a circula... A method of digitally high pass filtering in frequency domain is proposed to eliminate the background noise of the decoded image in Fresnel zone plate scanning holography. The high pass filter is designed as a circular stop, which should be suitable to suppressing the background noise significantly and remain much low frequency information of the object. The principle of high pass filtering is that the Fourier transform of the decoded image is multiplied with the high pass filter. Thus the frequency spectrum of the decoded image without the background noise is achieved. By inverse Fourier transform of the spectrum of the decoded image after multiplying operation, the decoded image without the background noise is obtained. Both of the computer simulations and the experimental results show that the contrast and the signal-to-noise ratio of the decoded image are significantly improved with digital filtering. 展开更多
关键词 Fresnel zone plate scanning holography digitally high pass filtering coded image decoded image
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Design and Implementation of Verification Code Identification Based on Anisotropic Heat Kernel 被引量:2
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作者 LIU Lizhao LIU Jian +3 位作者 DAI Yaomei XU Huarong YIN Huayi ZHU Shunzhi 《China Communications》 SCIE CSCD 2016年第1期100-112,共13页
Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as ... Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as entering the verification code manually.Improving the verification code security system needs the identification method as the corresponding testing system.We propose an anisotropic heat kernel equation group which can generate a heat source scale space during the kernel evolution based on infinite heat source axiom,design a multi-step anisotropic verification code identification algorithm which includes core procedure of building anisotropic heat kernel,settingwave energy information parameters,combing outverification codccharacters and corresponding peripheral procedure of gray scaling,binarizing,denoising,normalizing,segmenting and identifying,give out the detail criterion and parameter set.Actual test show the anisotropic heat kernel identification algorithm can be used on many kinds of verification code including text characters,mathematical,Chinese,voice,3D,programming,video,advertising,it has a higher rate of 25%and 50%than neural network and context matching algorithm separately for Yahoo site,49%and 60%for Captcha site,20%and 52%for Baidu site,60%and 65%for 3DTakers site,40%,and 51%.for MDP site. 展开更多
关键词 verification code image recognition data mining scale space anisotropic heat kernel
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Efficient Quadtree based Fractal Image Coding Scheme in Wavelet Transform Domain *
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作者 高西奇 洪波 +1 位作者 张辉 何振亚 《Journal of Southeast University(English Edition)》 EI CAS 1998年第1期35-40,共6页
This paper presents an efficient quadtree based fractal image coding scheme in wavelet transform domain based on the wavelet based theory of fractal image compression introduced by Davis. In the scheme, zerotrees of... This paper presents an efficient quadtree based fractal image coding scheme in wavelet transform domain based on the wavelet based theory of fractal image compression introduced by Davis. In the scheme, zerotrees of wavelet coefficients are used to reduce the number of domain blocks, which leads to lower bit cost required to represent the location information of fractal coding, and overall entropy constrained optimization is performed for the decision trees as well as for the sets of scalar quantizers and self quantizers of wavelet subtrees. Experiment results show that at the low bit rates, the proposed scheme gives about 1 dB improvement in PSNR over the reported results. 展开更多
关键词 fractal image coding wavelet transform QUADTREE
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Technique of Error Concealment for Block-Based Image Coding Using Genetic Algorithm
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作者 杨守义 罗伟雄 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期164-168,共5页
Since real world communication channels are not error free, the coded data transmitted on them may be corrupted, and block based image coding systems are vulnerable to transmission impairment. So the best neighborh... Since real world communication channels are not error free, the coded data transmitted on them may be corrupted, and block based image coding systems are vulnerable to transmission impairment. So the best neighborhood match method using genetic algorithm is used to conceal the error blocks. Experimental results show that the searching space can be greatly reduced by using genetic algorithm compared with exhaustive searching method, and good image quality is achieved. The peak signal noise ratios(PSNRs) of the restored images are increased greatly. 展开更多
关键词 block based image coding genetic algorithm error concealment
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Encoding methods matching the 16×16 pixel CZT detector of a coded aperture gamma camera 被引量:3
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作者 Xiao-Lei Shen Pin Gong +2 位作者 Xiao-Bin Tang Rui Zhang Jin-Chao Ma 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第9期82-89,共8页
With the advancements in nuclear energy,methods that can accurately obtain the spatial information of radioactive sources have become essential for nuclear energy safety.Coded aperture imaging technology is widely use... With the advancements in nuclear energy,methods that can accurately obtain the spatial information of radioactive sources have become essential for nuclear energy safety.Coded aperture imaging technology is widely used because it provides two-dimensional distribution information of radioactive sources.The coded array is a major component of a coded aperture gamma camera,and it affects the key performance parameters of the camera.Currently,commonly used coded arrays such as uniformly redundant arrays(URAs)and modified uniformly redundant arrays(MURAs)have prime numbers of rows or columns and may lead to wastage of detector pixels.A 16×16 coded array was designed on the basis of an existing 16×16 multi-pixel position-sensitive cadmium zinc telluride detector.The digital signal-to-noise(SNR)ratio of the point spread function at the center of the array is 25.67.Furthermore,Monte Carlo camera models and experimental devices based on rank-13 MURA and rank-16 URA have been constructed.With the same angular resolution,the field size of view under rank-16 URA is 1.53 times that of under rank-13 MURA.Simulations(Am-241,Co-57,Ir-192,Cs-137)and experiments(Co-57)are conducted to compare the imaging performance between rank-16 URA and rank-13 MURA.The contrast-to-noise ratio of the reconstructed image of the rank-16 array is great and only slightly lower than that of rank-13 MURA.However,as the photon energy increases,the gap becomes almost negligible. 展开更多
关键词 coded aperture imaging CZT Gamma camera Uniformly redundant arrays
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An Adaptive Block-Based Fractal Image Coding Scheme
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作者 邓元木 柯有安 《Journal of Beijing Institute of Technology》 EI CAS 1996年第2期183+177-183,共8页
Based on Jacquin's work. this paper presents an adaptive block-based fractal image coding scheme. Firstly. masking functions are used to classify range blocks and weight the mean Square error (MSE) of images. Seco... Based on Jacquin's work. this paper presents an adaptive block-based fractal image coding scheme. Firstly. masking functions are used to classify range blocks and weight the mean Square error (MSE) of images. Secondly, an adaptive block partition scheme is introduced by developing the quadtree partition method. Thirdly. a piecewise uniform quantization strategy is appled to quantize the luminance shifting. Finally. experiment results are shown and compared with what reported by Jacquin and Lu to verify the validity of the methods addressed by the authors. 展开更多
关键词 fractal technique image compression image coding
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Chaos-based encryption for fractal image coding 被引量:3
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作者 袁正雄 黄国和 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期115-126,共12页
A chaos-based cryptosystem for fractal image coding is proposed. The Renyi chaotic map is employed to determine the order of processing the range blocks and to generate the keystream for masking the encoded sequence. ... A chaos-based cryptosystem for fractal image coding is proposed. The Renyi chaotic map is employed to determine the order of processing the range blocks and to generate the keystream for masking the encoded sequence. Compared with the standard approach of fraetal image coding followed by the Advanced Encryption Standard, our scheme offers a higher sensitivity to both plaintext and ciphertext at a comparable operating efficiency. The keystream generated by the Renyi chaotic map passes the randomness tests set by the United States National Institute of Standards and Technology, and so the proposed scheme is sensitive to the key. 展开更多
关键词 CHAOS CRYPTOGRAPHY joint image compression and encryption fractal image coding
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Mean shift based log-Gabor wavelet image coding 被引量:2
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作者 LI Ji-liang FANG Xiang-zhong HOU Jun 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第4期620-624,共5页
In this paper, we propose a sparse overcomplete image approximation method based on the ideas of overcomplete log-Gabor wavelet, mean shift and energy concentration. The proposed approximation method selects the neces... In this paper, we propose a sparse overcomplete image approximation method based on the ideas of overcomplete log-Gabor wavelet, mean shift and energy concentration. The proposed approximation method selects the necessary wavelet coefficients with a mean shift based algorithm, and concentrates energy on the selected coefficients. It can sparsely approximate the original image, and converges faster than the existing local competition based method. Then, we propose a new compression scheme based on the above approximation method. The scheme has compression performance similar to JPEG 2000. The images decoded with the proposed compression scheme appear more pleasant to the human eyes than those with JPEG 2000. 展开更多
关键词 Sparse approximation LOG-GABOR image coding Mean shift Overcomolete
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FAST IMAGE ENCODING ALGORITHM BASED ON MEAN-MATCH CORRELATION VECTOR QUANTIZATION 被引量:1
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作者 徐润生 许晓鸣 张卫东 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第1期40-43,共4页
A mean-match correlation vector quantizer (MMCVQ) was presented for fast image encoding. In this algorithm, a sorted codebook is generated regarding the mean values of all codewords. During the encoding stage, high co... A mean-match correlation vector quantizer (MMCVQ) was presented for fast image encoding. In this algorithm, a sorted codebook is generated regarding the mean values of all codewords. During the encoding stage, high correlation of the adjacent image blocks is utilized, and a searching range is obtained in the sorted codebook according to the mean value of the current processing vector. In order to gain good performance, proper THd and NS are predefined on the basis of experimental experiences and additional distortion limitation. The expermental results show that the MMCVQ algorithm is much faster than the full-search VQ algorithm, and the encoding quality degradation of the proposed algorithm is only 0.3~0.4 dB compared to the full-search VQ. 展开更多
关键词 image coding vector quantization mean match method
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An improved deconvolution method for X-ray coded imaging in inertial confinement fusion
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作者 赵宗清 何卫华 +4 位作者 王剑 郝轶丹 曹磊峰 谷渝秋 张保汉 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期281-286,共6页
In inertial confinement fusion (ICF), X-ray coded imaging is considered as the most potential means to diagnose the compressed core. The traditional Richardson-Lucy (RL) method has a strong ability to deblur the i... In inertial confinement fusion (ICF), X-ray coded imaging is considered as the most potential means to diagnose the compressed core. The traditional Richardson-Lucy (RL) method has a strong ability to deblur the image where the noise follows the Poisson distribution. However, it always suffers from over-fitting and noise amplification, especially when the signal-to-noise ratio of image is relatively low. In this paper, we propose an improved deconvolution method for X-ray coded imaging. We model the image data as a set of independent Gaussian distributions and derive the iterative solution with a maximum-likelihood scheme. The experimental results on X-ray coded imaging data demonstrate that this method is superior to the RL method in terms of anti-overfitting and noise suppression. 展开更多
关键词 inertial confinement fusion coded imaging DECONVOLUTION Gaussian distribution MAXIMUM-LIKELIHOOD
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A HIGH SPEED ADAPTIVE FRACTAL IMAGE CODING ALGORITHM USING FLEXIBLE CLASSIFICATION TECHNIQUE
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作者 Zhang Liang Li Weihua Wang Qiao 《Wuhan University Journal of Natural Sciences》 CAS 1998年第2期146-146,共1页
Traditionally, fractal image compression suffers from lengthy encoding time in measure ofhours. In this paper, combined with characteristlcs of human visual system, a flexible classification technique is proposed. Thi... Traditionally, fractal image compression suffers from lengthy encoding time in measure ofhours. In this paper, combined with characteristlcs of human visual system, a flexible classification technique is proposed. This yields a corresponding adaptive algorithm which can cut down the encoding timeinto second's magnitude. Experiment results suggest that the algorithm can balance the overall encodingperformance efficiently, that is, with a higher speed and a better PSNR gain. 展开更多
关键词 image coding fractal image coding iterated function system (IFS) partitioned iterated function system (PIFS) characteristics of human visual system
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Lifting Scheme Based SPIHT Still Image Coding
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作者 沈利军 赵保军 何佩琨 《Journal of Beijing Institute of Technology》 EI CAS 2003年第S1期70-74,共5页
In order to eliminate float-point operations for fast wavelet transform, an integer D9/7 biorthogonal reversible wavelet transform was accomplished by lifting scheme. The lifting scheme based wavelet transform can be ... In order to eliminate float-point operations for fast wavelet transform, an integer D9/7 biorthogonal reversible wavelet transform was accomplished by lifting scheme. The lifting scheme based wavelet transform can be finished by addition and shift simply. It improved the quality of reconstructive image and greatly reduced the computational complexity due to integer operation. It is suitable for real-time image coding on hardware such as DSP. The simulation results show that the lifting scheme based SPIHT is prior to traditional wavelet based SPHIT in quality and complexity. 展开更多
关键词 SPIHT lifting scheme WAVELET image coding
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A Secure Public-key Image Authentication Plan
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作者 YANGQing CHENKe-fei 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期289-292,共4页
Digital watermark can be used for image ownership verification orauthentication. In this paper, we propose a new image authentication plan concentrating on itssecurity performance. Digital watermark is first turbo cod... Digital watermark can be used for image ownership verification orauthentication. In this paper, we propose a new image authentication plan concentrating on itssecurity performance. Digital watermark is first turbo coded, sealed and then processed. In waveletdomain. To enhance security level, public key cryptosystem is utilized to replace traditionalwatermark key. Simulation results are finally given by experiment. 展开更多
关键词 turbo code: image authentication public key cryptosystcm digital watermark
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High performance scalable image coding
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作者 Gan Tao He Yanmin Zhu Weile 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期795-800,共6页
A high performance scalable image coding algorithm is proposed. The salient features of this algorithm are the ways to form and locate the significant clusters. Thanks to the list structure, the new coding algorithm a... A high performance scalable image coding algorithm is proposed. The salient features of this algorithm are the ways to form and locate the significant clusters. Thanks to the list structure, the new coding algorithm achieves fine fractional bit-plane coding with negligible additional complexity. Experiments show that it performs comparably or better than the state-of-the-art coders. Furthermore, the flexible codec supports both quality and resolution scalability, which is very attractive in many network applications. 展开更多
关键词 scalable image coding significant clusters list structure
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An Adaptive Method of Image CompressionBased on Wavelet Analysis
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作者 Xu Hao Dept. of Biomedical Engineering, Shanghai Jiaotong University, 200030, P. R. China Yu Jun Dept. of Computer and Engineering, Hangzhou University of Commerce, 310035, P. R. China Yao Min Dept. of Computer, Zhejiang University, Hangzhou 310028, P. R. 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第1期53-58,共6页
Through research for image compression based on wavelet analysis in recent years, we put forward an adaptive wavelet decomposition strategy. Whether sub-images are to be decomposed or not are decided by their energy d... Through research for image compression based on wavelet analysis in recent years, we put forward an adaptive wavelet decomposition strategy. Whether sub-images are to be decomposed or not are decided by their energy defined by certain criterion. Then we derive the adaptive wavelet decomposition tree (AWDT) and the way of adjustable compression ratio. According to the feature of AWDT, this paper also deals with the strategies which are used to handle different sub-images in the procedure of quantification and coding of the wavelet coefficients. Through experiments, not only the algorithm in the paper can adapt to various images, but also the quality of recovered image is improved though compression ratio is higher and adjustable. When their compression ratios are near, the quality of subjective vision and PSNR of the algorithm are better than those of JPEG algorithm. 展开更多
关键词 Adaptive algorithms image coding image quality Signal to noise ratio Wavelet transforms
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REMOTE SENSING IMAGE CODING METHOD COMBINING WAVELET TRANSFORM WITH CLASSIFIED VECTOR QUANTIZATION
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作者 张正阳 吴成柯 《Chinese Journal of Aeronautics》 SCIE EI CSCD 1998年第3期55-60,共6页
A new remote sensing image coding scheme based on the wavelet transform and classified vector quantization (CVQ) is proposed. The original image is first decomposed into a hierarchy of 3 layers including 10 subimages ... A new remote sensing image coding scheme based on the wavelet transform and classified vector quantization (CVQ) is proposed. The original image is first decomposed into a hierarchy of 3 layers including 10 subimages by DWT. The lowest frequency subimage is compressed by scalar quantization and ADPCM. The high frequency subimages are compressed by CVQ to utilize the similarity among different resolutions while improving the edge quality and reducing computational complexity. The experimental results show that the proposed scheme has a better performance than JPEG, and a PSNR of reconstructed image is 31~33 dB with a rate of 0.2 bpp. 展开更多
关键词 remote sensing image coding wavelet transform classified vector quantization
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Novel region-based image compression method based on spiking cortical model
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作者 Rongchang Zhao Yide Ma 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期161-171,共11页
To get the high compression ratio as well as the high-quality reconstructed image, an effective image compression scheme named irregular segmentation region coding based on spiking cortical model(ISRCS) is presented... To get the high compression ratio as well as the high-quality reconstructed image, an effective image compression scheme named irregular segmentation region coding based on spiking cortical model(ISRCS) is presented. This scheme is region-based and mainly focuses on two issues. Firstly, an appropriate segmentation algorithm is developed to partition an image into some irregular regions and tidy contours, where the crucial regions corresponding to objects are retained and a lot of tiny parts are eliminated. The irregular regions and contours are coded using different methods respectively in the next step. The other issue is the coding method of contours where an efficient and novel chain code is employed. This scheme tries to find a compromise between the quality of reconstructed images and the compression ratio. Some principles and experiments are conducted and the results show its higher performance compared with other compression technologies, in terms of higher quality of reconstructed images, higher compression ratio and less time consuming. 展开更多
关键词 data compaction and compression image processing and computer vision region-based image coding neural network
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