Detecting Text in Natural Image with Connectionist Text Proposal Network

摘要

We propose a novel Connectionist Text Proposal Network (CTPN) that accuratelylocalizes text lines in natural image. The CTPN detects a text line in asequence of fine-scale text proposals directly in convolutional feature maps.We develop a vertical anchor mechanism that jointly predicts location andtext/non-text score of each fixed-width proposal, considerably improvinglocalization accuracy. The sequential proposals are naturally connected by arecurrent neural network, which is seamlessly incorporated into theconvolutional network, resulting in an end-to-end trainable model. This allowsthe CTPN to explore rich context information of image, making it powerful todetect extremely ambiguous text. The CTPN works reliably on multi-scale andmulti- language text without further post-processing, departing from previousbottom-up methods requiring multi-step post-processing. It achieves 0.88 and0.61 F-measure on the ICDAR 2013 and 2015 benchmarks, surpass- ing recentresults [8, 35] by a large margin. The CTPN is computationally efficient with0:14s/image, by using the very deep VGG16 model [27]. Online demo is availableat: http://textdet.com/.