In this paper, a new method to approximate the compensation term in the Jacobian logarithm used by the MAP decoder is proposed. Using the proposed approximation, the complex functions In（.） and exp（.） in the Exact...In this paper, a new method to approximate the compensation term in the Jacobian logarithm used by the MAP decoder is proposed. Using the proposed approximation, the complex functions In（.） and exp（.） in the Exact-log-MAP algorithm can be estimated with high accuracy and lower computational complexity. The efficacy of the proposed approximation is investigated and demonstrated by applying it to iteratively decoded BICM （Bit Interleaved Coded Modulation）.展开更多
为了对灰度不均匀图像进行分割,结合图像的局部和全局信息,提出基于加权L^(1)-L^(2)拟合能量项的模糊活动轮廓图像分割(fuzzy active contour based on weighted L^(1)-L^(2) fitting energy for image segmentation,FAWFE)模型。首先,...为了对灰度不均匀图像进行分割,结合图像的局部和全局信息,提出基于加权L^(1)-L^(2)拟合能量项的模糊活动轮廓图像分割(fuzzy active contour based on weighted L^(1)-L^(2) fitting energy for image segmentation,FAWFE)模型。首先,利用模糊隶属度函数,基于图像局部和全局信息构建混合模糊拟合图像。然后,构建加权L 1拟合能量项,量化原始图像与混合模糊拟合图像之间的差异,有效地处理灰度不均匀问题。最后,结合L^(2)拟合能量项,保证能量泛函的凸性,使得模型解的存在性和唯一性得以保证,避免陷入局部极小。另外,采用交替迭代算法对FAWFE模型进行数值求解,并与经典的活动轮廓模型对比。结果表明,FAWFE模型不仅可以准确定位目标边界,而且可以在0.6 s左右实现对图像的处理,对于合成图像和真实图像均有良好的处理效果。展开更多
文摘In this paper, a new method to approximate the compensation term in the Jacobian logarithm used by the MAP decoder is proposed. Using the proposed approximation, the complex functions In（.） and exp（.） in the Exact-log-MAP algorithm can be estimated with high accuracy and lower computational complexity. The efficacy of the proposed approximation is investigated and demonstrated by applying it to iteratively decoded BICM （Bit Interleaved Coded Modulation）.
文摘为了对灰度不均匀图像进行分割,结合图像的局部和全局信息,提出基于加权L^(1)-L^(2)拟合能量项的模糊活动轮廓图像分割(fuzzy active contour based on weighted L^(1)-L^(2) fitting energy for image segmentation,FAWFE)模型。首先,利用模糊隶属度函数,基于图像局部和全局信息构建混合模糊拟合图像。然后,构建加权L 1拟合能量项,量化原始图像与混合模糊拟合图像之间的差异,有效地处理灰度不均匀问题。最后,结合L^(2)拟合能量项,保证能量泛函的凸性,使得模型解的存在性和唯一性得以保证,避免陷入局部极小。另外,采用交替迭代算法对FAWFE模型进行数值求解,并与经典的活动轮廓模型对比。结果表明,FAWFE模型不仅可以准确定位目标边界,而且可以在0.6 s左右实现对图像的处理,对于合成图像和真实图像均有良好的处理效果。
