Various vision-based approaches, which utilize different types of low level features andclassifiers have been presented in the literature. In this section, we evaluate three differentapproaches for object classifications. This study is to select the best one which could lead to areliable solution for object classifications. The framework for object detection and recognitionis shown Fig. 12.Three methods for object detection are studied: Haar and Adaboost [29] HoG and SVM [7] GIST and k-NN [24], [22]As aforementioned, these methods are studied due to their effectiveness in classificationproblem. For each method, we proposed to recognize each object by a learning a binaryclassifier. At classification phase, sliding window technique is used to scan the whole image;16T¤p chí Khoa håc và Kÿ thuªt - Håc vi»n KTQS - Sè 164(10-2014)Inputimage/videoWindowsslidingFeatureextractionRecognition (Adaboost,SVM, KNN)Haar,HoG,GistResultDatabasePreprocessingFeatureextractionTraining (Adaboost,SVM, KNN)TrainedmodelsTraining phase Recognition phaseFig. 12. Generic framework of object recognition for comparative studyeach window candidate will be passed through feature extraction module then the computeddescriptor will be passed into the corresponding binary classifier as shown Fig. 12. For detailsof each method, the readers are invited to read the original papers.In this work, we are interested to detect and recognize four classes of obstacles: {Pottedplant, Trash, Extinguisher, and Human}. For training and testing detection and recognitionmethods, we have built a dataset containing 2104 images. The resolution of images is 600x400pixels. Each object class has 526 images under daylight condition in a corridor of a build. Thisdataset is very challenge because objects are taken under different views point and distances.Some examples are presented in the Fig. 13. All images in the database are annotated manuallyand organized in the directory. We divide the database into 2 parts: 504 images for trainingand 1600 images for testing.
đang được dịch, vui lòng đợi..
