优化截断嵌入式编码(Embedded block coding with optimized truncation,EBCOT)是JPEG2000的核心,EBCOT所采用的基于码块的率失真优化方式为实现图像感兴趣区(Region of interest,ROI)编码提供了良好的基础.本文分析了其中具有代表性的...优化截断嵌入式编码(Embedded block coding with optimized truncation,EBCOT)是JPEG2000的核心,EBCOT所采用的基于码块的率失真优化方式为实现图像感兴趣区(Region of interest,ROI)编码提供了良好的基础.本文分析了其中具有代表性的隐式ROI编码算法,并提出了一种改进方法.通过构造加权函数,合理地为ROI码块分配权重,在保证ROI信息被优先编码的同时,降低ROI码块中背景区域小波系数的影响,提高了重建图像ROI的质量.实验结果表明,算法在低码率下重建图像ROI质量提高明显,在高码率下也能够很好兼顾重建图像背景区域的质量.展开更多
An EBCOT-based method is proposed to reduce the priority of background coefficients in the ROI code block without compromising algorithm complexity. The region of interest is encoded to a higher quality level than bac...An EBCOT-based method is proposed to reduce the priority of background coefficients in the ROI code block without compromising algorithm complexity. The region of interest is encoded to a higher quality level than background, and the target searching time in video-guided penetrating missile can be shortened. Three kinds of coding schemes based on EBCOT are discussed. Experimental results demonstrate that the proposed method shows higher compression efficiency, lower complexity, and good reconstructed ROI image quality in the lower channel capacity.展开更多
针对JPEG2000中隐式ROI(Region of Interest)编码算法在低码率下重建图像感兴趣区质量较差的问题,提出了一种改进方法.利用拉格朗日插值法构造权重自适应函数,根据ROI码块中ROI小波系数个数所占比例及设定的目标码率,合理地为ROI码块分...针对JPEG2000中隐式ROI(Region of Interest)编码算法在低码率下重建图像感兴趣区质量较差的问题,提出了一种改进方法.利用拉格朗日插值法构造权重自适应函数,根据ROI码块中ROI小波系数个数所占比例及设定的目标码率,合理地为ROI码块分配权重,在保证更多ROI信息被优先编码的同时,降低背景小波系数的影响,从而提高了ROI小波系数在码流中的数据长度.实验结果表明,采用该算法,重建后感兴趣区图像质量较隐式ROI算法有明显提高.展开更多
文摘优化截断嵌入式编码(Embedded block coding with optimized truncation,EBCOT)是JPEG2000的核心,EBCOT所采用的基于码块的率失真优化方式为实现图像感兴趣区(Region of interest,ROI)编码提供了良好的基础.本文分析了其中具有代表性的隐式ROI编码算法,并提出了一种改进方法.通过构造加权函数,合理地为ROI码块分配权重,在保证ROI信息被优先编码的同时,降低ROI码块中背景区域小波系数的影响,提高了重建图像ROI的质量.实验结果表明,算法在低码率下重建图像ROI质量提高明显,在高码率下也能够很好兼顾重建图像背景区域的质量.
基金the National Defense Foundation Research (A2320060093)the National Natural Science Foundation of China (60572039)
文摘An EBCOT-based method is proposed to reduce the priority of background coefficients in the ROI code block without compromising algorithm complexity. The region of interest is encoded to a higher quality level than background, and the target searching time in video-guided penetrating missile can be shortened. Three kinds of coding schemes based on EBCOT are discussed. Experimental results demonstrate that the proposed method shows higher compression efficiency, lower complexity, and good reconstructed ROI image quality in the lower channel capacity.
文摘针对JPEG2000中隐式ROI(Region of Interest)编码算法在低码率下重建图像感兴趣区质量较差的问题,提出了一种改进方法.利用拉格朗日插值法构造权重自适应函数,根据ROI码块中ROI小波系数个数所占比例及设定的目标码率,合理地为ROI码块分配权重,在保证更多ROI信息被优先编码的同时,降低背景小波系数的影响,从而提高了ROI小波系数在码流中的数据长度.实验结果表明,采用该算法,重建后感兴趣区图像质量较隐式ROI算法有明显提高.