A benchmark image database of isolated Bangla handwritten compound characters

  • Nibaran Das
  • Kallol Acharya
  • Ram Sarkar
  • Subhadip Basu
  • Mahantapas Kundu
  • Mita Nasipuri
Original Paper


In the present work, we present a benchmark image database of isolated handwritten Bangla compound characters, used in the standard Bangla literature. A thorough survey over more than 2 million Bangla words has revealed that there exist around 334 compound characters in Bangla script. Of which, only around 171 character classes form unique pattern shapes, and some of these classes are often written in multiple styles. Altogether, 55,278 isolated character images, belonging to 199 different pattern shapes, are collected using three different data collection modalities. The database is divided into training and test sets in 4:1 ratio for each pattern class, by considering a balanced distribution of shapes from different modalities. A convex hull and quadtree-based feature set has been designed, and the test set recognition performance is reported with the support vector machine classifier. We have achieved a recognition accuracy of 79.35 % on the test database consisting of 171 character classes. The complete compound character image database is freely available as CMATERdb from the website, which may facilitate research on handwritten character recognition, especially related to Bangla form document processing systems.


OCR Handwritten character recognition Bangla Compound character Benchmark database SVM 



Authors are thankful to the “Center for Microprocessor Application for Training Education and Research”, “Project on Storage Retrieval and Understanding of Video for Multimedia” of Computer Science & Engineering Department, Jadavpur University, for providing infrastructure facilities during progress of the work. The work reported here has been partially funded by DST, Govt. of India, PURSE (Promotion of University Research and Scientific Excellence) Program.

Supplementary material

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Supplementary material 1 (pdf 4340 KB)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Nibaran Das
    • 1
  • Kallol Acharya
    • 1
  • Ram Sarkar
    • 1
  • Subhadip Basu
    • 1
  • Mahantapas Kundu
    • 1
  • Mita Nasipuri
    • 1
  1. 1.Computer Science and Engineering DepartmentJadavpur UniversityKolkata India

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