ChatReviewer / get_paper_from_pdf.py
czczup's picture
Duplicate from ShiwenNi/ChatReviewer
be6c855
import fitz, io, os
from PIL import Image
from collections import Counter
import json
import re
class Paper:
def __init__(self, path, title='', url='', abs='', authors=[]):
# 初始化函数,根据pdf路径初始化Paper对象
self.url = url # 文章链接
self.path = path # pdf路径
self.section_names = [] # 段落标题
self.section_texts = {} # 段落内容
self.abs = abs
self.title_page = 0
if title == '':
self.pdf = fitz.open(self.path) # pdf文档
self.title = self.get_title()
self.parse_pdf()
else:
self.title = title
self.authors = authors
self.roman_num = ["I", "II", 'III', "IV", "V", "VI", "VII", "VIII", "IIX", "IX", "X"]
self.digit_num = [str(d + 1) for d in range(10)]
self.first_image = ''
def parse_pdf(self):
self.pdf = fitz.open(self.path) # pdf文档
self.text_list = [page.get_text() for page in self.pdf]
self.all_text = ' '.join(self.text_list)
self.extract_section_infomation()
self.section_texts.update({"title": self.title})
self.pdf.close()
# 定义一个函数,根据字体的大小,识别每个章节名称,并返回一个列表
def get_chapter_names(self, ):
# # 打开一个pdf文件
doc = fitz.open(self.path) # pdf文档
text_list = [page.get_text() for page in doc]
all_text = ''
for text in text_list:
all_text += text
# # 创建一个空列表,用于存储章节名称
chapter_names = []
for line in all_text.split('\n'):
line_list = line.split(' ')
if '.' in line:
point_split_list = line.split('.')
space_split_list = line.split(' ')
if 1 < len(space_split_list) < 5:
if 1 < len(point_split_list) < 5 and (
point_split_list[0] in self.roman_num or point_split_list[0] in self.digit_num):
# print("line:", line)
chapter_names.append(line)
return chapter_names
def get_title(self):
doc = self.pdf # 打开pdf文件
max_font_size = 0 # 初始化最大字体大小为0
max_string = "" # 初始化最大字体大小对应的字符串为空
max_font_sizes = [0]
for page_index, page in enumerate(doc): # 遍历每一页
text = page.get_text("dict") # 获取页面上的文本信息
blocks = text["blocks"] # 获取文本块列表
for block in blocks: # 遍历每个文本块
if block["type"] == 0 and len(block['lines']): # 如果是文字类型
if len(block["lines"][0]["spans"]):
font_size = block["lines"][0]["spans"][0]["size"] # 获取第一行第一段文字的字体大小
max_font_sizes.append(font_size)
if font_size > max_font_size: # 如果字体大小大于当前最大值
max_font_size = font_size # 更新最大值
max_string = block["lines"][0]["spans"][0]["text"] # 更新最大值对应的字符串
max_font_sizes.sort()
# print("max_font_sizes", max_font_sizes[-10:])
cur_title = ''
for page_index, page in enumerate(doc): # 遍历每一页
text = page.get_text("dict") # 获取页面上的文本信息
blocks = text["blocks"] # 获取文本块列表
for block in blocks: # 遍历每个文本块
if block["type"] == 0 and len(block['lines']): # 如果是文字类型
if len(block["lines"][0]["spans"]):
cur_string = block["lines"][0]["spans"][0]["text"] # 更新最大值对应的字符串
font_flags = block["lines"][0]["spans"][0]["flags"] # 获取第一行第一段文字的字体特征
font_size = block["lines"][0]["spans"][0]["size"] # 获取第一行第一段文字的字体大小
# print(font_size)
if abs(font_size - max_font_sizes[-1]) < 0.3 or abs(font_size - max_font_sizes[-2]) < 0.3:
# print("The string is bold.", max_string, "font_size:", font_size, "font_flags:", font_flags)
if len(cur_string) > 4 and "arXiv" not in cur_string:
# print("The string is bold.", max_string, "font_size:", font_size, "font_flags:", font_flags)
if cur_title == '':
cur_title += cur_string
else:
cur_title += ' ' + cur_string
self.title_page = page_index
# break
title = cur_title.replace('\n', ' ')
return title
def extract_section_infomation(self):
doc = fitz.open(self.path)
# 获取文档中所有字体大小
font_sizes = []
for page in doc:
blocks = page.get_text("dict")["blocks"]
for block in blocks:
if 'lines' not in block:
continue
lines = block["lines"]
for line in lines:
for span in line["spans"]:
font_sizes.append(span["size"])
most_common_size, _ = Counter(font_sizes).most_common(1)[0]
# 按照最频繁的字体大小确定标题字体大小的阈值
threshold = most_common_size * 1
section_dict = {}
last_heading = None
subheadings = []
heading_font = -1
# 遍历每一页并查找子标题
found_abstract = False
upper_heading = False
font_heading = False
for page in doc:
blocks = page.get_text("dict")["blocks"]
for block in blocks:
if not found_abstract:
try:
text = json.dumps(block)
except:
continue
if re.search(r"\bAbstract\b", text, re.IGNORECASE):
found_abstract = True
last_heading = "Abstract"
section_dict["Abstract"] = ""
if found_abstract:
if 'lines' not in block:
continue
lines = block["lines"]
for line in lines:
for span in line["spans"]:
# 如果当前文本是子标题
if not font_heading and span["text"].isupper() and sum(1 for c in span["text"] if c.isupper() and ('A' <= c <='Z')) > 4: # 针对一些标题大小一样,但是全大写的论文
upper_heading = True
heading = span["text"].strip()
if "References" in heading: # reference 以后的内容不考虑
self.section_names = subheadings
self.section_texts = section_dict
return
subheadings.append(heading)
if last_heading is not None:
section_dict[last_heading] = section_dict[last_heading].strip()
section_dict[heading] = ""
last_heading = heading
if not upper_heading and span["size"] > threshold and re.match( # 正常情况下,通过字体大小判断
r"[A-Z][a-z]+(?:\s[A-Z][a-z]+)*",
span["text"].strip()):
font_heading = True
if heading_font == -1:
heading_font = span["size"]
elif heading_font != span["size"]:
continue
heading = span["text"].strip()
if "References" in heading: # reference 以后的内容不考虑
self.section_names = subheadings
self.section_texts = section_dict
return
subheadings.append(heading)
if last_heading is not None:
section_dict[last_heading] = section_dict[last_heading].strip()
section_dict[heading] = ""
last_heading = heading
# 否则将当前文本添加到上一个子标题的文本中
elif last_heading is not None:
section_dict[last_heading] += " " + span["text"].strip()
self.section_names = subheadings
self.section_texts = section_dict
def main():
path = r'demo.pdf'
paper = Paper(path=path)
paper.parse_pdf()
# for key, value in paper.section_text_dict.items():
# print(key, value)
# print("*"*40)
if __name__ == '__main__':
main()