2026-09-20T18:57:45Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/109535 2023-07-11 col_2142_5131 col_2142_10761 com_2142_5130 com_2142_10755 com_2142_234

Forsyth, David Alexander Zhang, Weilin 2021-03-05T21:42:52Z 2021-03-05T21:42:52Z 2023-03-05T21:43:00Z 2020-12-09 2020-12 Learning to detect an object in an image from very few training examples - few-shot object detection - is challenging, because the classifier that sees proposal boxes has very little training data. A particularly challenging training regime occurs when there are one or two training examples. In this case, if the region proposal network (RPN) misses even one high intersection-over-union (IOU) training box, the classifier's model of how object appearance varies can be severely impacted. We use multiple distinct yet cooperating RPN's. Our RPN's are trained to be different, but not too different; doing so yields significant performance improvements over state of the art for COCO and PASCAL VOC in the very few-shot setting. This effect appears to be independent of the choice of classifier or dataset. However, under the very low-shot regime, even if all high IOU boxes are used to train the classifier, the variations are still insufficient to train the classifier in novel classes. We propose to build an even better model of variation in novel classes by transferring the shared within-class variation from base classes. We introduce a hallucinator network and insert it into a modern object detector model, which learns to generate additional training examples in the Region of Interest (ROI's) feature space. This approach yields further performance improvements on two state-of-the-art few-shot detectors with different proposal generation processes. Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2022-12-01 The student, Weilin Zhang, accepted the attached license on 2020-12-08 at 16:29. The student, Weilin Zhang, submitted this Thesis for approval on 2020-12-08 at 16:37. This Thesis was approved for publication on 2020-12-09 at 15:03. DSpace SAF Submission Ingestion Package generated from Vireo submission #16094 on 2021-03-04 at 16:20:45 Made available in DSpace on 2021-03-05T21:42:52Z (GMT). No. of bitstreams: 2 ZHANG-THESIS-2020.pdf: 23061019 bytes, checksum: 1aa422e775a95bd91020fc090a9fdcdc (MD5) LICENSE.txt: 4209 bytes, checksum: ae8e6496cf2d269d7ab7c3ef04755004 (MD5) Previous issue date: 2020-12-09 Embargo set by: Seth Robbins for item 117240 Lift date: 2023-03-05T21:43:00Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system U of I Only application/pdf http://hdl.handle.net/2142/109535 en Copyright 2020 Weilin Zhang Object Detection Few-Shot Learning Improving few-shot object detection by saving and hallucinating examples text Thesis Computer Science Computer Science University of Illinois at Urbana-Champaign Thesis M.S.