Authors: Shanyu Xiao, Ruijie Yan, Meng Liu, Bowen Deng, Gang Yao, Liangrui Peng, Tsinghua University, Beijing, China
Description: We propose to use a one-stage detector to detect multiscale text regions, which incorporates a modified feature pyramid network (FPN) into the EAST  framework. For image preprocessing, a pixel level deformable module with linear spatial constraint is added before the FPN. In addition to the classification branch and RBOX branch in EAST, a center-ness regression branch  is adopted to suppress low-quality detected text boxes. In the training process, all loss maps are multiplied by the ground-truth center-ness map to reduce the loss weights at the text boxes’ border.
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