The prevalent scene text detection approach follows four sequential steps
comprising character candidate detection, false character candidate removal,
text line extraction, and text line verification. However, errors occur and
accumulate throughout each of these sequential steps which often lead to low
detection performance. To address these issues, we propose a unified scene text
detection system, namely Text Flow, by utilizing the minimum cost (min-cost)
flow network model. With character candidates detected by cascade boosting, the
min-cost flow network model integrates the last three sequential steps into a
single process which solves the error accumulation problem at both character
level and text line level effectively. The proposed technique has been tested
on three public datasets, i.e, ICDAR2011 dataset, ICDAR2013 dataset and a
multilingual dataset and it outperforms the state-of-the-art methods on all
three datasets with much higher recall and F-score. The good performance on the
multilingual dataset shows that the proposed technique can be used for the
detection of texts in different languages.

该研究提出了一种名为 Text Flow 的统一场景文本检测系统，该系统使用了最小成本（min-cost）流网络模型，通过将字符候选检测、文本行提取和文本行验证三个步骤集成到一个过程中，从而有效地解决了误差累积问题，并在 ICDAR2011，ICDAR2013 和多语种数据集上都实现了比现有技术更高的检测精度。

自然场景图像中的统一文本检测系统

Text Flow: A Unified Text Detection System in Natural Scene Images

Text detection in natural scene images is an important prerequisite for many
content-based image analysis tasks. In this paper, we propose an accurate and
robust method for detecting texts in natural scene images. A fast and effective
pruning algorithm is designed to extract Maximally Stable Extremal Regions
(MSERs) as character candidates using the strategy of minimizing regularized
variations. Character candidates are grouped into text candidates by the
ingle-link clustering algorithm, where distance weights and threshold of the
clustering algorithm are learned automatically by a novel self-training
distance metric learning algorithm. The posterior probabilities of text
candidates corresponding to non-text are estimated with an character
classifier; text candidates with high probabilities are then eliminated and
finally texts are identified with a text classifier. The proposed system is
evaluated on the ICDAR 2011 Robust Reading Competition dataset; the f measure
is over 76% and is significantly better than the state-of-the-art performance
of 71%. Experimental results on a publicly available multilingual dataset also
show that our proposed method can outperform the other competitive method with
the f measure increase of over 9 percent. Finally, we have setup an online demo
of our proposed scene text detection system at
this http URL

本文提出了一种准确和鲁棒性较高的文本检测方法，通过设计快速有效的剪枝算法，使用最小化正则化变化策略来提取极值区域，然后通过单链接聚类算法将字符候选分组为文本候选，在使用一种自学习距离度量算法自动学习距离权重和聚类算法的阈值来识别文本候选，并使用字符分类器估计相应的文本候选的后验概率来消除具有高概率的非文本文本候选，并最终识别出文本。通过实验结果证明，该方法的检测效果优于其他竞争方法。