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This overview explores the field of Content-Based Image Retrieval (CBIR), discussing its academic significance and real-world applications. The text highlights the challenges faced in CBIR, including problems of object recognition, feature extraction, and evaluation metrics. It examines various research efforts and methodologies, such as MPEG-7 descriptors and the Bag of Features approach. By analyzing the evolution of image retrieval systems and their performance metrics, this work provides valuable insights into the complexities of organizing and retrieving digital images effectively.
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Overview of Image Retrieval Hui-Ying Wang
Reference • Smeulders, A. W., Worring, M., Santini, S., Gupta, A., , and Jain, R. 2000. “Content-based image retrieval at the end of the early years.” IEEE Trans. Pattern Analysis and Machine Intelligence 22, 12, 1349–1380. • R. Datta, D. Joshi, J. Li and J. Z. Wang, ”Image Retrieval: Ideas, Influences, and Trends of the New Age,” ACM Computing Surveys, 2008, to appear. • CVPR 2007 short course: Recognizing and Learning Object Categories http://people.csail.mit.edu/torralba/shortCourseRLOC/index.html
Outline • Motive • Academic and real world • Difficulties and problem model • Evaluation metrics
Outline • Motive • Academic and real world • Difficulties and problem model • Evaluation metrics
Motive • Popular electronic device • Digital camera • By-product • Digital photos • Need • Organization • Key: filenames? dates?
Outline • Motive • Academic and real world • Difficulties and problem model • Evaluation metrics
Search engines Google Image (2.2 b) Picsearch (1.7 b) Yahoo! Images (1.6 b) AltaVista Ask Images Online albums Flickr Riya Webshots Shopping like Real-world system
Search engines Google Image (2.2 b) Picsearch (1.7 b) Yahoo! Images (1.6 b) AltaVista Ask Images Online albums Flickr Riya Webshots Shopping like Real-world system
Search engines Google Image (2.2 b) Picsearch (1.7 b) Yahoo! Images (1.6 b) AltaVista Ask Images Online albums Flickr Riya Webshots Shopping like Real-world system
Search engines Google Image (2.2 b) Picsearch (1.7 b) Yahoo! Images (1.6 b) AltaVista Ask Images Online albums Flickr Riya Webshots Shopping like Real-world system
Outline • Motive • Academic and real world • Difficulties and problem model • Evaluation metrics
Challenges view point variation occlusion scale deformation illumination
Goal computer vision real object sensory gap digital record interpretation semantic gap extraction human vision
Core problems • How to describe an image • How to assess the similarity
Some features • Global features • MPEG-7 • Color Layout Descriptor • Edge Histogram Descriptor • Homogeneous Texture Descriptor • Summarizing local features • Bag of Features
Some features • Global features • MPEG-7 • Color Layout Descriptor • Edge Histogram Descriptor • Homogeneous Texture Descriptor • Summarizing local features • Bag of Features
Some features • Global features • MPEG-7 • Color Layout Descriptor • Edge Histogram Descriptor • Homogeneous Texture Descriptor • Summarizing local features • Bag of Features
Some features • Global features • MPEG-7 • Color Layout Descriptor • Edge Histogram Descriptor • Homogeneous Texture Descriptor • Summarizing local features • Bag of Features
Homogeneous Texture Descriptor - Presentation Fourier transform Gabor function e: log-scaled sum of the squares of Gabor-filtered Fourier transform coefficients d: log-scaled standard deviation of the squares of Gabor-filtered Fourier transform coefficients Human Vision System fDC: mean deviation fSD: standard deviation
Some features • Global features • MPEG-7 • Color Layout Descriptor • Edge Histogram Descriptor • Homogeneous Texture Descriptor • Summarizing local features • Bag of Features
Local feature • Detected keypoints • spatial relationship • fully independent (ex: bag of features) • fully connected
Outline • Motive • Academic and real world • Difficulties and problem model • Evaluation metrics
Evaluation (1/2) • Standard • Precision • # of retrieved positive images / # of total retrieved images • Recall • # of retrieved positive images / # of total positive images
Evaluation (1/2) • When number of retrieved images increase • Recall ↑ Precision ↓ • Average precision (AP) • The area under the precision-recall curve for a query 1 AP precision 1 recall
The end ~ Thank you