A Method for Removing Stains from Images of Ancient Books and Documents
A document image and stain removal technology, which is applied in the field of ancient book document image stain removal, can solve the problems of poor binarization effect and inability to remove stains, etc., and achieve a good binarization effect
Active Publication Date: 2021-12-31
NORTHWEST UNIVERSITY FOR NATIONALITIES
View PDF15 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0006] In order to solve the problems in the prior art that the stains in the image cannot be removed by methods such as Otsu, Niblack, and Sauvola, and the binarization effect is poor, the present invention provides a method for removing stains from images of ancient book documents, which uses the Lab color space Three channels, to obtain the position information of the stain to weaken and eliminate the influence of the stain, and use the automatic block method to binarize the image blocks to obtain the binary image of the entire image, laying the foundation for further line word segmentation and recognition
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0043] In order to make the object, technical solution and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with the examples. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.
[0044] The application principle of the present invention will be described in detail below in conjunction with the accompanying drawings.
[0045] Such as figure 1 As shown, a method for removing stains from an image of an ancient book document is specifically carried out in accordance with the following steps:
[0046] S101: Stain treatment:
[0047] The image to be processed (such as figure 2 Described) is converted to Lab color space by RGB color space, the numerical value of three channel images L, a, b of Lab color space calculates according to formula (1), (2), (3), (4):
[0048]
[0049]
[0050]
[00...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention discloses a method for removing stains from an image of an ancient book document. The method converts the image to be processed from the RGB color space to the Lab color space, uses three channel images of the Lab color space to separate it, and utilizes the different channel images after separation. Self-information, choose L channel and b channel for fusion to weaken or eliminate the influence of stains; automatically determine the size of the image text block according to the number and size of the text in the image after the stain is removed, and judge whether the block image needs to be extended; The binary image is obtained by combining global and local binarization processing on the image blocks. The present invention separates the three channel images of the Lab color space and then fuses the two channels, which solves the problem of stain removal in the text images of ancient books; in the process of binarization, the image is automatically divided into blocks, and the global and Partial combination can effectively remove stains in ancient book document images, and the binarization effect is good.
Description
technical field [0001] The invention belongs to the technical field of document analysis and recognition, and in particular relates to a method for removing stains from images of ancient book documents. Background technique [0002] Image binarization is often used in document image restoration. Image binarization can be divided into grayscale image binarization and color image binarization. Therefore, the selection of the threshold has a decisive effect on the image binarization result. Due to the age, many pages of ancient books have stains. How to remove the stains, obtain effective binary images of Tibetan ancient books, and then perform document segmentation and character recognition is an important link. [0003] At present, the threshold-based binarization method can be divided into global threshold method and local threshold method. The global threshold method uses a single threshold for the entire image, and judges the target and background by comparing all pixel v...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): G06T7/11G06T5/50
Inventor 王维兰韩跃辉王轶群
Owner NORTHWEST UNIVERSITY FOR NATIONALITIES