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 处理的核心操作。根据底部快速参考表选择合适的工具。

提示: 本项目内置多个 PDF 相关工具，优先使用它们。以下 Python/命令行指南用于更复杂的场景。

使用内置工具（推荐）

读取 PDF

<read_document>
<uri>/path/to/document.pdf</uri>
</read_document>

合并多个 PDF

<pdf_operation>
<operation>merge</operation>
<input_files>["/path/to/doc1.pdf", "/path/to/doc2.pdf"]</input_files>
<output_path>/path/to/merged.pdf</output_path>
</pdf_operation>

拆分 PDF

<pdf_operation>
<operation>split</operation>
<input_file>/path/to/document.pdf</input_file>
<output_dir>/path/to/output/</output_dir>
<options>{"from_page":1,"to_page":5}</options>
</pdf_operation>

添加水印

<pdf_operation>
<operation>watermark</operation>
<input_file>/path/to/document.pdf</input_file>
<output_path>/path/to/watermarked.pdf</output_path>
<watermark_text>机密文件</watermark_text>
<options>{"font_size":48,"opacity":0.3,"angle":45}</options>
</pdf_operation>

转换格式（PDF↔Word/图片）

<document_convert>
<input_file>/path/to/document.pdf</input_file>
<output_path>/path/to/document.docx</output_path>
<format>docx</format>
</document_convert>

提取 PDF 中的图片

<document_extract>
<input_file>/path/to/document.pdf</input_file>
<output_dir>/path/to/images/</output_dir>
<extract_type>images</extract_type>
</document_extract>

如需填写 PDF 表单，请加载捆绑资源 FORMS.md。

---

Quick Start

from pypdf import PdfReader, PdfWriter

# Read a PDF
reader = PdfReader("document.pdf")
print(f"Pages: {len(reader.pages)}")

# Extract text
text = ""
for page in reader.pages:
    text += page.extract_text()

Python Libraries

pypdf - Basic Operations

Merge PDFs

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)

Split PDF

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)

Extract Metadata

reader = PdfReader("document.pdf")
meta = reader.metadata
print(f"Title: {meta.title}")
print(f"Author: {meta.author}")
print(f"Subject: {meta.subject}")
print(f"Creator: {meta.creator}")

Rotate Pages

reader = PdfReader("input.pdf")
writer = PdfWriter()

page = reader.pages[0]
page.rotate(90)  # Rotate 90 degrees clockwise
writer.add_page(page)

with open("rotated.pdf", "wb") as output:
    writer.write(output)

pdfplumber - Text and Table Extraction

Extract Text with Layout

import pdfplumber

with pdfplumber.open("document.pdf") as pdf:
    for page in pdf.pages:
        text = page.extract_text()
        print(text)

Extract Tables

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"Table {j+1} on page {i+1}:")
            for row in table:
                print(row)

Advanced Table Extraction (to Excel)

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:
                df = pd.DataFrame(table[1:], columns=table[0])
                all_tables.append(df)

if all_tables:
    combined_df = pd.concat(all_tables, ignore_index=True)
    combined_df.to_excel("extracted_tables.xlsx", index=False)

reportlab - Create PDFs

Basic PDF Creation

from reportlab.lib.pagesizes import letter
from reportlab.pdfgen import canvas

c = canvas.Canvas("hello.pdf", pagesize=letter)
width, height = letter

c.drawString(100, height - 100, "Hello World!")
c.drawString(100, height - 120, "This is a PDF created with reportlab")
c.line(100, height - 140, 400, height - 140)
c.save()

Create PDF with Multiple Pages

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 = []

title = Paragraph("Report Title", styles['Title'])
story.append(title)
story.append(Spacer(1, 12))

body = Paragraph("This is the body of the report. " * 20, styles['Normal'])
story.append(body)
story.append(PageBreak())

story.append(Paragraph("Page 2", styles['Heading1']))
story.append(Paragraph("Content for page 2", styles['Normal']))

doc.build(story)

Subscripts and Superscripts

IMPORTANT: Never use Unicode subscript/superscript characters (₀₁₂₃₄₅₆₇₈₉, ⁰¹²³⁴⁵⁶⁷⁸⁹) in ReportLab PDFs. The built-in fonts do not include these glyphs, causing them to render as solid black boxes.

Use ReportLab's XML markup tags in Paragraph objects instead:

from reportlab.platypus import Paragraph
from reportlab.lib.styles import getSampleStyleSheet

styles = getSampleStyleSheet()

# Subscripts: use <sub> tag
chemical = Paragraph("H<sub>2</sub>O", styles['Normal'])

# Superscripts: use <super> tag
squared = Paragraph("x<super>2</super> + y<super>2</super>", styles['Normal'])

Command-Line Tools

pdftotext (poppler-utils)

# Extract text
pdftotext input.pdf output.txt

# Extract text preserving layout
pdftotext -layout input.pdf output.txt

# Extract specific pages
pdftotext -f 1 -l 5 input.pdf output.txt

qpdf

# Merge PDFs
qpdf --empty --pages file1.pdf file2.pdf -- merged.pdf

# Split pages
qpdf input.pdf --pages . 1-5 -- pages1-5.pdf
qpdf input.pdf --pages . 6-10 -- pages6-10.pdf

# Rotate pages
qpdf input.pdf output.pdf --rotate=+90:1

# Remove password
qpdf --password=mypassword --decrypt encrypted.pdf decrypted.pdf

pdftk (if available)

# Merge
pdftk file1.pdf file2.pdf cat output merged.pdf

# Split
pdftk input.pdf burst

# Rotate
pdftk input.pdf rotate 1east output rotated.pdf

Common Tasks

Extract Text from Scanned PDFs (OCR)

# Requires: pip install pytesseract pdf2image
import pytesseract
from pdf2image import convert_from_path

images = convert_from_path('scanned.pdf')

text = ""
for i, image in enumerate(images):
    text += f"Page {i+1}:\n"
    text += pytesseract.image_to_string(image)
    text += "\n\n"

print(text)

Add Watermark

from pypdf import PdfReader, PdfWriter

watermark = PdfReader("watermark.pdf").pages[0]

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)

Extract Images

# Using pdfimages (poppler-utils)
pdfimages -j input.pdf output_prefix
# Extracts all images as output_prefix-000.jpg, output_prefix-001.jpg, etc.

Password Protection

from pypdf import PdfReader, PdfWriter

reader = PdfReader("input.pdf")
writer = PdfWriter()

for page in reader.pages:
    writer.add_page(page)

writer.encrypt("userpassword", "ownerpassword")

with open("encrypted.pdf", "wb") as output:
    writer.write(output)

PDF to Images (for preview/thumbnails)

# Requires: pip install pdf2image
from pdf2image import convert_from_path

# Convert all pages to images
images = convert_from_path('document.pdf', dpi=200)

for i, image in enumerate(images):
    image.save(f'page_{i+1}.png', 'PNG')

Add Page Numbers

from pypdf import PdfReader, PdfWriter
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import letter
import io

reader = PdfReader("input.pdf")
writer = PdfWriter()

for i, page in enumerate(reader.pages):
    # Create page number overlay
    packet = io.BytesIO()
    c = canvas.Canvas(packet, pagesize=letter)
    c.setFont("Helvetica", 10)
    c.drawCentredString(letter[0] / 2, 30, f"Page {i + 1} of {len(reader.pages)}")
    c.save()
    packet.seek(0)

    # Merge overlay with original page
    overlay = PdfReader(packet).pages[0]
    page.merge_page(overlay)
    writer.add_page(page)

with open("numbered.pdf", "wb") as output:
    writer.write(output)

Quick Reference

Task	Best Tool	Key Function
Merge PDFs	pypdf	writer.add_page(page)
Split PDFs	pypdf	One page per PdfWriter
Extract text	pdfplumber	page.extract_text()
Extract tables	pdfplumber	page.extract_tables()
Create PDFs	reportlab	Canvas or Platypus
Rotate pages	pypdf	page.rotate(degrees)
Add watermark	pypdf	page.merge_page(watermark)
Password protect	pypdf	writer.encrypt(password)
OCR scanned PDFs	pytesseract + pdf2image	Convert to image → OCR
Command line merge	qpdf	qpdf --empty --pages ...
Extract images	poppler-utils	pdfimages -j input.pdf prefix
PDF to images	pdf2image	convert_from_path()
Add page numbers	pypdf + reportlab	Create overlay → merge

Installation

# Core libraries
pip install pypdf pdfplumber reportlab

# For OCR
pip install pytesseract pdf2image

# For table extraction to Excel
pip install pandas openpyxl

# Command-line tools (Ubuntu/Debian)
sudo apt-get install poppler-utils qpdf

# Command-line tools (macOS)
brew install poppler qpdf

# Command-line tools (Windows - using chocolatey)
choco install poppler qpdf