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<< 点击显示目录 >> 主页 mappVision帮助助手 > 机器视觉帮助 > mapp Vision > 用例 > 深度 OCR - 读取长字符串 |
本节介绍视觉功能深度 OCR 的基本建议，以及读取长字符串（超过 27 个字符）的建议。
以下几个方面对于长字符串的良好识别效果非常重要：
•良好的打印质量和打印字符的均匀性
•尽可能均匀的背景
•字符与背景之间有足够的对比度
信息：
视觉功能 Deep OCR 是针对单词进行训练的。因此强烈建议为每个字符串（单词）定义一个 ROI！
The ROI should be as small as possible. It should include at most the character string with a small quiet zone.
SearchAngle 定义文本的搜索方向。每次使用 OCR 功能时只能设置一次。SearchAngle 必须与要读取的文本精确对齐，否则会影响文本的可识别性。
信息：
使用 TestExecute = 1，可在 mapp Vision 人机界面应用程序中显示找到的文本区域。
信息：
字符识别质量可通过使用循环参数 MinConfidenceLevel、NumberDiscardedCharacters 和 ConfidenceLevel 进行评估。
置信度本身并不能作为字符串打印质量的参考！
不包括的字符： λ, Ω, £.
This section describes basic recommendations for vision function Deep OCR, as well as recommendations for reading long character strings (more than 27 characters).
The following aspects are important for a good recognition result of long character strings:
•Good print quality and homogeneity of the printed characters
•A background that is as homogeneous as possible
•Sufficient contrast between characters and background
Information:
Vision function Deep OCR is trained for single words. It is therefore strongly recommended to define one ROI per character string (one word)!
The ROI should be as small as possible. It should include at most the character string with a small quiet zone.
SearchAngle defines the search direction for a text. This can only be set once each time an OCR function used. An exact alignment of SearchAngle to the text to be read is necessary and affects the recognizability of the text.
Information:
The found text regions can be displayed in the mapp Vision HMI application by using TestExecute = 1.
Information:
The quality of character recognition can be evaluated via using the cyclic parameters MinConfidenceLevel, NumberDiscardedCharacters and ConfidenceLevel.
ConfidenceLevel alone is not a reference for the print quality of a character string!
Excluded characters: λ, Ω, £.