pdf-processor

# PDF 处理指南 ## 概述 本指南涵盖使用 Python 库和命令行工具进行 PDF 处理的基本操作。 ## 快速开始 ```python from pypdf import PdfReader, PdfWriter # 读取 PDF reader = PdfReader("document.pdf") print(f"页数: {len(reader.pages)}") # 提取文本 text = "" for page in reader.pages: text += page.extract_text() ``` ## Python 库 ### pypdf - 基本操作 #### 合并 PDF ```python from pypdf import PdfWriter, PdfReader writer = PdfWriter() for pdf_file in ["doc1.pdf", "doc2.pdf", "doc3.pdf"]: reader = PdfReader(pdf_file) for page in reader.pages: writer.add_page(page) with open("merged.pdf", "wb") as output: writer.write(output) ``` #### 拆分 PDF ```python reader = PdfReader("input.pdf") for i, page in enumerate(reader.pages): writer = PdfWriter() writer.add_page(page) with open(f"page_{i+1}.pdf", "wb") as output: writer.write(output) ``` #### 提取元数据 ```python reader = PdfReader("document.pdf") meta = reader.metadata print(f"标题: {meta.title}") print(f"作者: {meta.author}") print(f"主题: {meta.subject}") print(f"创建者: {meta.creator}") ``` #### 旋转页面 ```python reader = PdfReader("input.pdf") writer = PdfWriter() page = reader.pages[0] page.rotate(90) # 顺时针旋转 90 度 writer.add_page(page) with open("rotated.pdf", "wb") as output: writer.write(output) ``` ### pdfplumber - 文本和表格提取 #### 提取文本（保持布局） ```python import pdfplumber with pdfplumber.open("document.pdf") as pdf: for page in pdf.pages: text = page.extract_text() print(text) ``` #### 提取表格 ```python with pdfplumber.open("document.pdf") as pdf: for i, page in enumerate(pdf.pages): tables = page.extract_tables() for j, table in enumerate(tables): print(f"第 {i+1} 页的表格 {j+1}:") for row in table: print(row) ``` #### 高级表格提取 ```python import pandas as pd with pdfplumber.open("document.pdf") as pdf: all_tables = [] for page in pdf.pages: tables = page.extract_tables() for table in tables: if table: # 检查表格非空 df = pd.DataFrame(table[1:], columns=table[0]) all_tables.append(df) # 合并所有表格 if all_tables: combined_df = pd.concat(all_tables, ignore_index=True) combined_df.to_excel("extracted_tables.xlsx", index=False) ``` ### reportlab - 创建 PDF #### 基本 PDF 创建 ```python from reportlab.lib.pagesizes import letter from reportlab.pdfgen import canvas c = canvas.Canvas("hello.pdf", pagesize=letter) width, height = letter # 添加文本 c.drawString(100, height - 100, "Hello World!") c.drawString(100, height - 120, "这是一个使用 reportlab 创建的 PDF") # 添加线条 c.line(100, height - 140, 400, height - 140) # 保存 c.save() ``` #### 创建多页 PDF ```python from reportlab.lib.pagesizes import letter from reportlab.platypus import SimpleDocTemplate, Paragraph, Spacer, PageBreak from reportlab.lib.styles import getSampleStyleSheet doc = SimpleDocTemplate("report.pdf", pagesize=letter) styles = getSampleStyleSheet() story = [] # 添加内容 title = Paragraph("报告标题", styles['Title']) story.append(title) story.append(Spacer(1, 12)) body = Paragraph("这是报告正文。 " * 20, styles['Normal']) story.append(body) story.append(PageBreak()) # 第 2 页 story.append(Paragraph("第 2 页", styles['Heading1'])) story.append(Paragraph("第 2 页的内容", styles['Normal'])) # 构建 PDF doc.build(story) ``` ## 命令行工具 ### pdftotext (poppler-utils) ```bash # 提取文本 pdftotext input.pdf output.txt # 提取文本并保持布局 pdftotext -layout input.pdf output.txt # 提取特定页面 pdftotext -f 1 -l 5 input.pdf output.txt # 第 1-5 页 ``` ### qpdf ```bash # 合并 PDF qpdf --empty --pages file1.pdf file2.pdf -- merged.pdf # 拆分页面 qpdf input.pdf --pages . 1-5 -- pages1-5.pdf qpdf input.pdf --pages . 6-10 -- pages6-10.pdf # 旋转页面 qpdf input.pdf output.pdf --rotate=+90:1 # 将第 1 页旋转 90 度 # 移除密码 qpdf --password=mypassword --decrypt encrypted.pdf decrypted.pdf ``` ## 常见任务 ### 添加水印 ```python from pypdf import PdfReader, PdfWriter # 创建水印（或加载现有水印） watermark = PdfReader("watermark.pdf").pages[0] # 应用到所有页面 reader = PdfReader("document.pdf") writer = PdfWriter() for page in reader.pages: page.merge_page(watermark) writer.add_page(page) with open("watermarked.pdf", "wb") as output: writer.write(output) ``` ### 密码保护 ```python from pypdf import PdfReader, PdfWriter reader = PdfReader("input.pdf") writer = PdfWriter() for page in reader.pages: writer.add_page(page) # 添加密码 writer.encrypt("userpassword", "ownerpassword") with open("encrypted.pdf", "wb") as output: writer.write(output) ``` ## 快速参考 | 任务 | 最佳工具 | 命令/代码 | |------|---------|----------| | 合并 PDF | pypdf | `writer.add_page(page)` | | 拆分 PDF | pypdf | 每页一个文件 | | 提取文本 | pdfplumber | `page.extract_text()` | | 提取表格 | pdfplumber | `page.extract_tables()` | | 创建 PDF | reportlab | Canvas 或 Platypus | | 命令行合并 | qpdf | `qpdf --empty --pages ...` | ## 依赖要求 - **pypdf**: `pip install pypdf` - **pdfplumber**: `pip install pdfplumber` - **reportlab**: `pip install reportlab` - **pandas**: `pip install pandas` (用于表格导出) 命令行工具： - **poppler-utils**: `sudo apt-get install poppler-utils` (Linux) - **qpdf**: `sudo apt-get install qpdf` (Linux)