Question

我试图阅读一个pdf文件，其中每个页面被分成3x3格式的信息块

A | B | C
D | E | F
G | H | I

每个条目分为多行。一个条目的简化示例是this card。但是在其他8个插槽中会有类似的条目。

我看过pdfminer和pypdf2。我还没有发现pdfminer过于有用，但pypdf2给了我一些接近的东西。

import PyPDF2
from StringIO import StringIO
def getPDFContent(path):
    content = ""
    p = file(path, "rb")
    pdf = PyPDF2.PdfFileReader(p)
    numPages = pdf.getNumPages()
    for i in range(numPages):
        content += pdf.getPage(i).extractText() + "\n"
    content = " ".join(content.replace(u"\xa0", " ").strip().split())
    return content

但是，这只能逐行读取文件。我想要一个解决方案，我只能读取页面的一部分，以便我可以读取A，然后是B，然后是C，依此类推。此外，答案here工作得相当好，但顺序为列经常被扭曲，我只能逐行阅读。

Answer 1

我认为有问题的PDF文件是生成的PDF而不是扫描（如您给出的示例中所示），因为您正在使用pdfminer和pypdf2。如果您知道以英寸为单位的列和行的大小，则可以使用minecart（完全披露：我写了minecart）。示例代码：

import minecart

# minecart units are 1/72 inch, measured from bottom-left of the page
ROW_BORDERS = (
    72 * 1,  # Bottom row starts 1 inch from the bottom of the page
    72 * 3,  # Second row starts 3 inches from the bottom of the page
    72 * 5,  # Third row starts 5 inches from the bottom of the page
    72 * 7,  # Third row ends 7 inches from the bottom of the page
)
COLUMN_BORDERS = (
    72 * 8,  # Third col ends 8 inches from the left of the page
    72 * 6,  # Third col starts 6 inches from the left of the page
    72 * 4,  # Second col starts 4 inches from the left of the page   
    72 * 2,  # First col starts 2 inches from the left of the page
)  # reversed so that BOXES is ordered properly
BOXES = [
    (left, bot, right, top)
    for top, bot in zip(ROW_BORDERS, ROW_BORDERS[1:])
    for left, right in zip(COLUMN_BORDERS, COLUMN_BORDERS[1:])
]

def extract_output(page):
    """
    Reads the text from page and splits it into the 9 cells.

    Returns a list with 9 entries: 

        [A, B, C, D, E, F, G, H, I]

    Each item in the tuple contains a string with all of the
    text found in the cell.

    """
    res = []
    for box in BOXES:
        strings = list(page.letterings.iter_in_bbox(box))
        # We sort from top-to-bottom and then from left-to-right, based
        # on the strings' top left corner
        strings.sort(key=lambda x: (-x.bbox[3], x.bbox[0]))
        res.append(" ".join(strings).replace(u"\xa0", " ").strip())
    return res

content = []
doc = minecart.Document(open("path/to/pdf-doc.pdf", 'rb'))
for page in doc.iter_pages():
    content.append(extract_output(page))

Python阅读pdf页面的一部分

1 个答案: