• 中国计算机学会会刊
  • 中国科技核心期刊
  • 中文核心期刊

计算机工程与科学 ›› 2022, Vol. 44 ›› Issue (01): 102-109.

• 图形与图像 • 上一篇    下一篇

面向智能手机拍摄的变形文档图像校正

周丽,冯百明,关煜,方格   

  1. (西北师范大学计算机科学与工程学院, 甘肃 兰州 730070 )
  • 收稿日期:2020-08-16 修回日期:2020-10-15 接受日期:2022-01-25 出版日期:2022-01-25 发布日期:2022-01-13
  • 基金资助:
    国家自然科学基金(61662067,61967013,61462076)

Correcting distorted document images on smartphones

ZHOU Li,FENG Bai-ming,GUAN Yu,FANG Ge#br#

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  1. (College of Computer Science and Engineering,Northwest Normal University,Lanzhou 730070,China)
  • Received:2020-08-16 Revised:2020-10-15 Accepted:2022-01-25 Online:2022-01-25 Published:2022-01-13

摘要: 智能手机拍摄的图像中经常会出现变形的文档图像,变形的文档图像影响文本的识别和后期图像处理等工作,而现有的变形文档图像校正方法存在校正类型单一和校正效果不理想的问题。针对以上问题,提出了一种基于最小化重投影的变形文档图像校正方法。该方法首先通过文本域轮廓检测,合并文本域轮廓来获取文本行连通域。然后利用主成分分析法PCA在行连通域生成文本关键点。最后通过最小化关键点和其投影点之间的距离获取重采样参数,再对变形的页面进行最小化重投影来进行文档图像校正。校正后识别率得到有效提高,相比现有方法,所提方法取得了更好的识别效果,且使用消融实验验证了文本域合并和最小化重投影这2个模块对识别性能的提升效果。

关键词: 变形文档图像, 文本域轮廓检测, PCA, 最小化重投影, 文档图像校正

Abstract: Distorted document images usually appear in smartphone images, which causes a lot of inconvenience for users. These images affect text recognition, post-processing, etc. Existing distorted document image correction methods have some limitations such as single correction type and unsatisfactory correction effect. To solve the above problems, an distorted document image correction method based on minimizing re-projection is proposed. Firstly, the connected domain of text lines is obtained by detecting text field contour and merging text field contour. Secondly, PCA (Principal Component 
Ana- lysis) is adopted to generate key points of text in the connected domain of the row. Finally, resampled parameters are obtained by minimizing the distance between the key points and their projection points. The distorted pages are re-projected to minimize the document image correction. After correction, the recognition rate is effectively improved. Compared with the existing methods, a better recognition effect is achieved. Moreover, ablation experiments are used to verify the improvement effect of text field merging and minimization re-projection on the recognition performance respectively.


Key words: distorted document image, text field contour detection, PCA, minimizes re-projection, document image correction