Where’s Wally? A machine learning approach

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  • CGVC__Where_s_Wally(1)

    Accepted author manuscript, 2.27 MB, PDF document


Object detection has been implemented in all sorts of real-life scenarios such as facial recognition, traffic monitoring and medical imaging but the research that has gone into object detection in drawings and cartoons is not nearly as extensive. The Where's Wally puzzle books give a good opportunity to implement some of these real-life methods into the fictional world. The Wally detection framework proposed is composed of two stages: i) a Haar-cascade classifier based on the Viola-Jones framework, which detects possible candidates from a scenario from the Where's Wally books, and ii) a lightweight convolutional neural network (CNN) that re-labels the objects detected by the cascade classifier. The cascade classifier was trained on 85 positive images and 172 negative images. It was then applied to 12 test images, which produced over 400 false positives. To increase the accuracy of the models, hard negative mining was implemented. The framework achieved a recall score of 84.61% and an F1 score of 78.54%. Improvements could be made to the training data or the CNN to further increase these scores.
Original languageEnglish
Title of host publicationComputer Graphics & Visual Computing (CGVC) 2021
EditorsK. Xu, M. Turner
PublisherThe Eurographics Association
Publication statusPublished - Sep 2021
EventEG UK Computer Graphics & Visual Computing (CGVC): EGUK CGVC 2021 - Lincoln, United Kingdom
Duration: 8 Sep 202110 Sep 2021
Conference number: 39


ConferenceEG UK Computer Graphics & Visual Computing (CGVC)
Abbreviated titleCGVC 2021
Country/TerritoryUnited Kingdom
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