使用pdfminer实现pdf文件的布局分析 python
参考资料：
https://github.com/euske/pdfminer
https://stackoverflow.com/questions/22898145/how-to-extract-text-and-text-coordinates-from-a-pdf-file?noredirect=1
import cv2from pdfminer.pdfparser import PDFParserfrom pdfminer.pdfdocument import PDFDocumentfrom pdfminer.pdfpage import PDFPagefrom pdfminer.pdfpage import PDFTextExtractionNotAllowedfrom pdfminer.pdfinterp import PDFResourceManagerfrom pdfminer.pdfinterp import PDFPageInterpreterfrom pdfminer.pdfdevice import PDFDevicefrom pdfminer.layout import LAParamsfrom pdfminer.converter import PDFPageAggregatorimport pdfminerimport numpy as npimport matplotlib.pyplot as pltfrom pdf2image import convert_from_pathimage_path = 'literature.pdf'layout_type = ['LTTextBox', 'LTFigure', 'LTImage', 'LTCurve', 'LTRect']# Text：红色， Figure：绿色， Image：蓝色， Curve：黄色， Rect：紫色color = [(255, 0, 0), (0, 255, 0), (0, 0, 255), (255, 255, 0), (160, 32, 240)]draw_color = dict(zip(layout_type, color))def parse_obj(lt_objs):boxs = {x: [] for x in layout_type}# loop over the object listfor obj in lt_objs:if isinstance(obj, pdfminer.layout.LTTextBoxHorizontal):boxs['LTTextBox'].append(obj.bbox)elif isinstance(obj, pdfminer.layout.LTFigure):boxs['LTFigure'].append(obj.bbox)elif isinstance(obj, pdfminer.layout.LTImage):boxs['LTImage'].append(obj.bbox)elif isinstance(obj, pdfminer.layout.LTCurve):boxs['LTCurve'].append(obj.bbox)elif isinstance(obj, pdfminer.layout.LTRect):boxs['LTRect'].append(obj.bbox)else:raisereturn boxs# Open a PDF file.fp = open(image_path, 'rb')# Create a PDF parser object associated with the file object.parser = PDFParser(fp)# Create a PDF document object that stores the document structure.# Supply the password for initialization.password = '123'document = PDFDocument(parser, password)# Check if the document allows text extraction. If not, abort.if not document.is_extractable:raise PDFTextExtractionNotAllowed# Create a PDF resource manager object that stores shared resources.rsrcmgr = PDFResourceManager()# Set parameters for analysis.laparams = LAParams()# Create a PDF page aggregator object.device = PDFPageAggregator(rsrcmgr, laparams=laparams)interpreter = PDFPageInterpreter(rsrcmgr, device)page_boxs = []for page in PDFPage.create_pages(document):interpreter.process_page(page)# receive the LTPage object for the page.layout = device.get_result()# extract text from this objectboxs = parse_obj(layout._objs)page_sized = tuple([round(i) for i in layout.bbox])page_boxs.append((page_sized, boxs))passimage = convert_from_path(image_path)assert len(image) == len(page_boxs), "The number of boxes doesn't match the number of pictures"for i in range(len(image)):# 得到这一页图片image_pil = image[i]# 把这一页的图片格式转成numpy类型image_numpy = np.array(image_pil)# 得到这一页图片德国高度，为了之后得到实际的boxpage_boxs_height = page_boxs[i][0][3]print(page_boxs[i][1])# 遍历这一页的框for key, values in page_boxs[i][1].items():# 把实际的图片大小resize到页面的大小image_numpy = cv2.resize(image_numpy, page_boxs[i][0][2:4], interpolation=cv2.INTER_AREA)for value in values:# The y-coordinates are given as the distance from the bottom of the page.real_box = (value[0], page_boxs_height-value[3], value[2], page_boxs_height-value[1])real_box_integer = tuple([round(jj) for jj in real_box])# 画图cv2.rectangle(image_numpy, real_box_integer[:2], real_box_integer[2:], draw_color[key], 2)plt.figure(), plt.imshow(image_numpy)plt.show()结果如下：
此代码只涉及到PDF文件的布局分析，没有涉及到PDF转成可编辑文档。供大家参考，有问题希望大家多多指正