Computer-aided diagnosis of pneumonia based on deep learning is a research hotspot.However,there are some problems that the features of different sizes and different directions are not sufficient when extracting the f...Computer-aided diagnosis of pneumonia based on deep learning is a research hotspot.However,there are some problems that the features of different sizes and different directions are not sufficient when extracting the features in lung X-ray images.A pneumonia classification model based on multi-scale directional feature enhancement MSD-Net is proposed in this paper.The main innovations are as follows:Firstly,the Multi-scale Residual Feature Extraction Module(MRFEM)is designed to effectively extract multi-scale features.The MRFEM uses dilated convolutions with different expansion rates to increase the receptive field and extract multi-scale features effectively.Secondly,the Multi-scale Directional Feature Perception Module(MDFPM)is designed,which uses a three-branch structure of different sizes convolution to transmit direction feature layer by layer,and focuses on the target region to enhance the feature information.Thirdly,the Axial Compression Former Module(ACFM)is designed to perform global calculations to enhance the perception ability of global features in different directions.To verify the effectiveness of the MSD-Net,comparative experiments and ablation experiments are carried out.In the COVID-19 RADIOGRAPHY DATABASE,the Accuracy,Recall,Precision,F1 Score,and Specificity of MSD-Net are 97.76%,95.57%,95.52%,95.52%,and 98.51%,respectively.In the chest X-ray dataset,the Accuracy,Recall,Precision,F1 Score and Specificity of MSD-Net are 97.78%,95.22%,96.49%,95.58%,and 98.11%,respectively.This model improves the accuracy of lung image recognition effectively and provides an important clinical reference to pneumonia Computer-Aided Diagnosis.展开更多
针对二进制描述算法(Oriented fast and Rotated Brief,ORB)尺度性配准误差大,配准率低的问题,提出一种尺度和方向改进的ORB特征匹配算法。该算法以二进制描述算法ORB为基础,构建金字塔式尺度空间,改进尺度空间结构,简化尺度空间层数和...针对二进制描述算法(Oriented fast and Rotated Brief,ORB)尺度性配准误差大,配准率低的问题,提出一种尺度和方向改进的ORB特征匹配算法。该算法以二进制描述算法ORB为基础,构建金字塔式尺度空间,改进尺度空间结构,简化尺度空间层数和采样图像数目,使提取特征点的过程更加效率,并采用Harris函数检测特征,消除边缘特征点的影响,提取具有尺度信息的特征点;然后采用梯度方向统计方法改进传统ORB算法中通过灰度质心法计算主方向的方式,优化求解主方向邻域范围,以提高图像特征主方向的准确性。实验结果表明,改进后的ORB算法在尺度和旋转配准方面性能有很大提高,并且配准的精度较传统ORB更高,更能满足复杂图像快速精确配准的要求。展开更多
基金supported in part by the National Natural Science Foundation of China(Grant No.62062003)Natural Science Foundation of Ningxia(Grant No.2023AAC03293).
文摘Computer-aided diagnosis of pneumonia based on deep learning is a research hotspot.However,there are some problems that the features of different sizes and different directions are not sufficient when extracting the features in lung X-ray images.A pneumonia classification model based on multi-scale directional feature enhancement MSD-Net is proposed in this paper.The main innovations are as follows:Firstly,the Multi-scale Residual Feature Extraction Module(MRFEM)is designed to effectively extract multi-scale features.The MRFEM uses dilated convolutions with different expansion rates to increase the receptive field and extract multi-scale features effectively.Secondly,the Multi-scale Directional Feature Perception Module(MDFPM)is designed,which uses a three-branch structure of different sizes convolution to transmit direction feature layer by layer,and focuses on the target region to enhance the feature information.Thirdly,the Axial Compression Former Module(ACFM)is designed to perform global calculations to enhance the perception ability of global features in different directions.To verify the effectiveness of the MSD-Net,comparative experiments and ablation experiments are carried out.In the COVID-19 RADIOGRAPHY DATABASE,the Accuracy,Recall,Precision,F1 Score,and Specificity of MSD-Net are 97.76%,95.57%,95.52%,95.52%,and 98.51%,respectively.In the chest X-ray dataset,the Accuracy,Recall,Precision,F1 Score and Specificity of MSD-Net are 97.78%,95.22%,96.49%,95.58%,and 98.11%,respectively.This model improves the accuracy of lung image recognition effectively and provides an important clinical reference to pneumonia Computer-Aided Diagnosis.
文摘针对二进制描述算法(Oriented fast and Rotated Brief,ORB)尺度性配准误差大,配准率低的问题,提出一种尺度和方向改进的ORB特征匹配算法。该算法以二进制描述算法ORB为基础,构建金字塔式尺度空间,改进尺度空间结构,简化尺度空间层数和采样图像数目,使提取特征点的过程更加效率,并采用Harris函数检测特征,消除边缘特征点的影响,提取具有尺度信息的特征点;然后采用梯度方向统计方法改进传统ORB算法中通过灰度质心法计算主方向的方式,优化求解主方向邻域范围,以提高图像特征主方向的准确性。实验结果表明,改进后的ORB算法在尺度和旋转配准方面性能有很大提高,并且配准的精度较传统ORB更高,更能满足复杂图像快速精确配准的要求。
