ocr - 具有表格或行的文档的 Tesseract OCR 文本顺序

Question

我正在使用 Tesseract OCR将扫描的 PDF 转换为纯文本。总体而言，它非常有效，但我对扫描文本的顺序有疑问。带有表格数据的文档似乎是逐列向下扫描，而更自然的方式是逐行扫描。一个非常小的例子是:

This is column A, row 1   This is column B, row 1    This is column C, row 1
This is column A, row 2   This is column B, row 2    This is column C, row 2

正在产生以下文本:

This is column A, row 1
This is column A, row 2
This is column B, row 1
This is column B, row 2
This is column C, row 1
This is column C, row 2

我开始阅读文档并使用 parameters documented here 进行猜测和测试，蛮力方法但如果有人已经解决了类似的问题，我将不胜感激对修复的见解。它也可能是一些训练数据，但我不知道它是如何工作的。

Answer 1

尝试在单列之一中运行 tesseract Page Segmentation Modes :
tesseract input.tif output-filename --psm 6

By default Tesseract expects a page of text when it segments an image. If you're just seeking to OCR a small region try a different segmentation mode, using the -psm argument. Note that adding a white border to text which is too tightly cropped may also help, see issue 398.

To see a complete list of supported page segmentation modes, use tesseract -h. Here's the [ed: excerpt only] list as of 3.21:

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.

请参阅此处的示例: #using-different-page-segmentation-modes