Phương pháp phục hồi hình ảnh ký tự cho nhận dạng chữ Hán viết tay không bị ràng buộc

Springer Science and Business Media LLC - Tập 18 Số 1 - Trang 73-86 - 2015
Shao, Yunxue1, Wang, Chunheng2, Xiao, Baihua2
1College of Computer Science, Inner Mongolia University, Hohhot, Inner Mongolia, China
2Institute of Automation, Chinese Academy of Sciences, Beijing, China

Tóm tắt

Mặc dù đã có những thành công với các phương pháp dựa trên cơ sở dữ liệu chữ viết tay có ràng buộc, việc nhận dạng chữ Hán viết tay không bị ràng buộc vẫn là một thách thức lớn. Một khó khăn trong việc nhận dạng chữ viết tay không bị ràng buộc là một số nét vẽ bị kết nối hoặc một số nét bị om. Trong bài báo này, chúng tôi đề xuất một phương pháp phục hồi hình ảnh ký tự cho việc nhận dạng chữ Hán viết tay không bị ràng buộc. Trong phương pháp này, hình ảnh ký tự quan sát được mô hình hóa như là sự kết hợp giữa hình ảnh ký tự lý tưởng với hai loại hình ảnh nhiễu: hình ảnh nhiễu nét bị om và hình ảnh nhiễu nét được thêm vào. Để giữ lại các đặc điểm gradient gốc, việc phục hồi được thực hiện trên các đặc điểm gradient. Các đặc điểm được ước lượng sau đó được sử dụng để phân biệt những ký tự tương tự. Để chứng minh tính hiệu quả của phương pháp đề xuất, chúng tôi đã mở rộng một số bộ phân loại hiện đại dựa trên các đặc điểm ước lượng. Kết quả thực nghiệm cho thấy các bộ phân loại mở rộng vượt trội hơn so với các bộ phân loại hiện đại ban đầu. Điều này chứng tỏ rằng các đặc điểm ước lượng là hữu ích để cải thiện thêm tỷ lệ nhận diện.

Từ khóa

#nhận dạng chữ Hán #viết tay không bị ràng buộc #phục hồi hình ảnh ký tự #đặc điểm gradient #bộ phân loại

Tài liệu tham khảo

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