A novel histogram descriptor for global feature extraction and description was presented. Three elementary primitives for a 2×2 pixel grid were defined. The complex primitives were computed by matrix transforms. ...A novel histogram descriptor for global feature extraction and description was presented. Three elementary primitives for a 2×2 pixel grid were defined. The complex primitives were computed by matrix transforms. These primitives and equivalence class were used for an image to compute the feature image that consisted of three elementary primitives. Histogram was used for the transformed image to extract and describe the features. Furthermore, comparisons were made among the novel histogram descriptor, the gray histogram and the edge histogram with regard to feature vector dimension and retrieval performance. The experimental results show that the novel histogram can not only reduce the effect of noise and illumination change, but also compute the feature vector of lower dimension. Furthermore, the system using the novel histogram has better retrieval performance.展开更多
An automatic approach is presented to track a wide screen in a multipurpose hall video scene. Once the screen is located, this system also generates the temporal rate of change by using the edge detection based method...An automatic approach is presented to track a wide screen in a multipurpose hall video scene. Once the screen is located, this system also generates the temporal rate of change by using the edge detection based method. Our approach adopts a scene segmentation algorithm that explores visual features (texture) and depth information to perform efficient screen localization. The cropped region which refers to the wide screen undergoes salient visual cues extraction to retrieve the emphasized changes required in rate-of- change computation. In addition to video document indexing and retrieval, this work can improve the machine vision capability in the behavior analysis and pattern recognition.展开更多
This paper presents a travel-aid system for sight-impaired pedestrians in outdoor environment.Unlike many existing travel-aid systems that rely on stereo-vision,the proposed system aims to detect generic obstacles in ...This paper presents a travel-aid system for sight-impaired pedestrians in outdoor environment.Unlike many existing travel-aid systems that rely on stereo-vision,the proposed system aims to detect generic obstacles in a cluttered road environment by using just the single camera attached to user's body.To achieve this goal,the original image is re-sampled and mapped to a bird-eye view virtual plane,on which background edges are sub-sampled while obstacle edges are oversampled.Morphology filters with connected component analysis are used to enhance obstacle edges as edge-blobs with larger size,whereas sparse edges from background are filtered out.Based on the identified obstacles,safe walking areas are estimated by calculating a polar edge histogram.The algorithm is tested in different sidewalk scenes with complex pavements,and its efficiency has been confirmed.展开更多
基金Project(60873010) supported by the National Natural Science Foundation of ChinaProjects(N090504005, N090604012, N090104001) supported by the Fundamental Research Funds for the Central UniversitiesProject(NCET-05-0288) supported by Program for New Century Excellent Talents in University
文摘A novel histogram descriptor for global feature extraction and description was presented. Three elementary primitives for a 2×2 pixel grid were defined. The complex primitives were computed by matrix transforms. These primitives and equivalence class were used for an image to compute the feature image that consisted of three elementary primitives. Histogram was used for the transformed image to extract and describe the features. Furthermore, comparisons were made among the novel histogram descriptor, the gray histogram and the edge histogram with regard to feature vector dimension and retrieval performance. The experimental results show that the novel histogram can not only reduce the effect of noise and illumination change, but also compute the feature vector of lower dimension. Furthermore, the system using the novel histogram has better retrieval performance.
文摘An automatic approach is presented to track a wide screen in a multipurpose hall video scene. Once the screen is located, this system also generates the temporal rate of change by using the edge detection based method. Our approach adopts a scene segmentation algorithm that explores visual features (texture) and depth information to perform efficient screen localization. The cropped region which refers to the wide screen undergoes salient visual cues extraction to retrieve the emphasized changes required in rate-of- change computation. In addition to video document indexing and retrieval, this work can improve the machine vision capability in the behavior analysis and pattern recognition.
基金The MKE(The Ministry of Knowledge Economy),Korea,under the ITRC(Infor mation Technology Research Center)support programsupervised by the NIPA(National IT Industry Promotion Agency)(NIPA-2012-(C1090-1021-0010))The Brain Korea 21 Project in 2012
文摘This paper presents a travel-aid system for sight-impaired pedestrians in outdoor environment.Unlike many existing travel-aid systems that rely on stereo-vision,the proposed system aims to detect generic obstacles in a cluttered road environment by using just the single camera attached to user's body.To achieve this goal,the original image is re-sampled and mapped to a bird-eye view virtual plane,on which background edges are sub-sampled while obstacle edges are oversampled.Morphology filters with connected component analysis are used to enhance obstacle edges as edge-blobs with larger size,whereas sparse edges from background are filtered out.Based on the identified obstacles,safe walking areas are estimated by calculating a polar edge histogram.The algorithm is tested in different sidewalk scenes with complex pavements,and its efficiency has been confirmed.