python的tesseract库几个重要的命令
在调用tesseract时,最重要的三个参数是 -l, -oem 和 -psm
-l 参数控制识别文本的语言。可以通过命令 tesseract --list-langs 查看已经安装的字库。
支持中文:下载中文扩展 https://github.com/tesseract-ocr/tessdata, 把里面的 chi_sim.traineddata 复制到 **\Tesseract-OCR\tessdata 的路径。
-oem 参数控制OCR的引擎模式,控制由超正方体使用的算法类型。可以通过命令 tesseract --help-oem 查看可用的引擎模式, 一般有四种模式,默认第四种, 可以用 --oem 1表示只希望用深度学习LSTM引擎。
OCR Engine modes:
0 Legacy engine only.
1 Neural nets LSTM engine only.
2 Legacy + LSTM engines.
3 Default, based on what is available.
-psm 参数控制tesseract使用的自动页面分割模式。使用 tesseract --help-psm 查看模式, 我发现对于小文本,模式6和7运行良好,如果是大块文本,可以试试默认的3模式。
Page segmentation modes:
0 Orientation and script detection (OSD) only.
1 Automatic page segmentation with OSD.
2 Automatic page segmentation, but no OSD, or OCR.
3 Fully automatic page segmentation, but no OSD. (Default)
4 Assume a single column of text of variable sizes.
5 Assume a single uniform block of vertically aligned text.
6 Assume a single uniform block of text.
7 Treat the image as a single text line.
8 Treat the image as a single word.
9 Treat the image as a single word in a circle.
10 Treat the image as a single character.
11 Sparse text. Find as much text as possible in no particular order.
12 Sparse text with OSD.
13 Raw line. Treat the image as a single text line,
bypassing hacks that are Tesseract-specific.
使用:
img = Image.open('./img.png') config = ("-l chi_sim --oem 1 --psm 7") text = pytesseract.image_to_string(img, config=config)