Ground penetrating radar(GPR),as a fast,efficient,and non-destructive detection device,holds great potential for the detection of shallow subsurface environments,such as urban road subsurface monitoring.However,the in...Ground penetrating radar(GPR),as a fast,efficient,and non-destructive detection device,holds great potential for the detection of shallow subsurface environments,such as urban road subsurface monitoring.However,the interpretation of GPR echo images often relies on manual recognition by experienced engineers.In order to address the automatic interpretation of cavity targets in GPR echo images,a recognition-algorithm based on Gaussian mixed model-hidden Markov model(GMM-HMM)is proposed,which can recognize three dimensional(3D)underground voids automatically.First,energy detection on the echo images is performed,whereby the data is preprocessed and pre-filtered.Then,edge histogram descriptor(EHD),histogram of oriented gradient(HOG),and Log-Gabor filters are used to extract features from the images.The traditional method can only be applied to 2D images and pre-processing is required for C-scan images.Finally,the aggregated features are fed into the GMM-HMM for classification and compared with two other methods,long short-term memory(LSTM)and gate recurrent unit(GRU).By testing on a simulated dataset,an accuracy rate of 90%is obtained,demonstrating the effectiveness and efficiency of our proposed method.展开更多
行人检测是目标识别领域的一大难题,针对行人检测存在特征维度高、检测耗时和精度低等问题,文章提出使用多尺度分块方式将样本图片在3个尺度下分别分割成5个区域,在每个区域中根据行人轮廓置信模板和梯度方向量化权值进行二次加权统计...行人检测是目标识别领域的一大难题,针对行人检测存在特征维度高、检测耗时和精度低等问题,文章提出使用多尺度分块方式将样本图片在3个尺度下分别分割成5个区域,在每个区域中根据行人轮廓置信模板和梯度方向量化权值进行二次加权统计得到梯度直方图(histogram of oriented gradient,HOG),并将其与Sobel边缘局部二元模式(Sobel edge local binary pattern,Sobel-LBP)算法相融合作为特征,然后采用线性支持向量机(support vector machine,SVM)分类方法学习得到行人检测分类器,最后使用滑动窗口法检测出行人。在MIT和INRIA库上的实验证明,该特征在学习和检测速度上都比HOG等方法有明显优势,能有效、准确、快速地检测行人。展开更多
基金National Natural Science Foundation of China(62071147)。
文摘Ground penetrating radar(GPR),as a fast,efficient,and non-destructive detection device,holds great potential for the detection of shallow subsurface environments,such as urban road subsurface monitoring.However,the interpretation of GPR echo images often relies on manual recognition by experienced engineers.In order to address the automatic interpretation of cavity targets in GPR echo images,a recognition-algorithm based on Gaussian mixed model-hidden Markov model(GMM-HMM)is proposed,which can recognize three dimensional(3D)underground voids automatically.First,energy detection on the echo images is performed,whereby the data is preprocessed and pre-filtered.Then,edge histogram descriptor(EHD),histogram of oriented gradient(HOG),and Log-Gabor filters are used to extract features from the images.The traditional method can only be applied to 2D images and pre-processing is required for C-scan images.Finally,the aggregated features are fed into the GMM-HMM for classification and compared with two other methods,long short-term memory(LSTM)and gate recurrent unit(GRU).By testing on a simulated dataset,an accuracy rate of 90%is obtained,demonstrating the effectiveness and efficiency of our proposed method.
文摘行人检测是目标识别领域的一大难题,针对行人检测存在特征维度高、检测耗时和精度低等问题,文章提出使用多尺度分块方式将样本图片在3个尺度下分别分割成5个区域,在每个区域中根据行人轮廓置信模板和梯度方向量化权值进行二次加权统计得到梯度直方图(histogram of oriented gradient,HOG),并将其与Sobel边缘局部二元模式(Sobel edge local binary pattern,Sobel-LBP)算法相融合作为特征,然后采用线性支持向量机(support vector machine,SVM)分类方法学习得到行人检测分类器,最后使用滑动窗口法检测出行人。在MIT和INRIA库上的实验证明,该特征在学习和检测速度上都比HOG等方法有明显优势,能有效、准确、快速地检测行人。