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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.
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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