PDF Processing Guide
Overview
This guide covers essential PDF processing operations using Python libraries and command-line tools. For advanced features, JavaScript libraries, and detailed examples, see reference.md. If you need to fill out a PDF form, read forms.md and follow its instructions.
Quick Start
python
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
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)
Split 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)
Extract Metadata
python
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
python
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
python
import pdfplumber
with pdfplumber.open("document.pdf") as pdf:
for page in pdf.pages:
text = page.extract_text()
print(text)
Extract Tables
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"Table {j+1} on page {i+1}:")
for row in table:
print(row)
Advanced Table Extraction
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: # Check if table is not empty
df = pd.DataFrame(table[1:], columns=table[0])
all_tables.append(df)
# Combine all tables
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
python
from reportlab.lib.pagesizes import letter
from reportlab.pdfgen import canvas
c = canvas.Canvas("hello.pdf", pagesize=letter)
width, height = letter
# Add text
c.drawString(100, height - 100, "Hello World!")
c.drawString(100, height - 120, "This is a PDF created with reportlab")
# Add a line
c.line(100, height - 140, 400, height - 140)
# Save
c.save()
Create PDF with Multiple Pages
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 = []
# Add content
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())
# Page 2
story.append(Paragraph("Page 2", styles['Heading1']))
story.append(Paragraph("Content for page 2", styles['Normal']))
# Build PDF
doc.build(story)
Create PDF with Japanese Text (reportlab)
python
from reportlab.lib.pagesizes import letter
from reportlab.platypus import SimpleDocTemplate, Paragraph, Spacer
from reportlab.lib.styles import ParagraphStyle
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont
# Register Japanese font
pdfmetrics.registerFont(TTFont('JP', '/usr/share/fonts/opentype/ipafont-gothic/ipag.ttf'))
# Define Japanese style
jp_style = ParagraphStyle(
'Japanese',
fontName='JP',
fontSize=12,
spaceAfter=10
)
doc = SimpleDocTemplate("report_ja.pdf", pagesize=letter)
story = []
# Add Japanese content
story.append(Paragraph("日本語レポート", jp_style))
story.append(Paragraph("これはreportlabで作成した日本語のテキストです。", jp_style))
doc.build(story)
Available Fonts
| Font | Path | Language Support |
|---|---|---|
| Noto Sans CJK JP (Regular) | /usr/share/fonts/opentype/noto/NotoSansCJK-Regular.ttc | Chinese, Japanese, Korean |
| Noto Sans CJK JP (Bold) | /usr/share/fonts/opentype/noto/NotoSansCJK-Bold.ttc | Chinese, Japanese, Korean |
| Noto Sans Mono CJK JP (Regular) | /usr/share/fonts/opentype/noto/NotoSansCJK-Regular.ttc | Chinese, Japanese, Korean |
| Noto Serif CJK JP (Regular) | /usr/share/fonts/opentype/noto/NotoSerifCJK-Regular.ttc | Chinese, Japanese, Korean |
| Noto Serif CJK JP (Bold) | /usr/share/fonts/opentype/noto/NotoSerifCJK-Bold.ttc | Chinese, Japanese, Korean |
| IPA Gothic | /usr/share/fonts/opentype/ipafont-gothic/ipag.ttf | Japanese (Gothic) |
| IPA Mincho | /usr/share/fonts/opentype/ipafont-mincho/ipam.ttf | Japanese (Serif) |
Command-Line Tools
pdftotext (poppler-utils)
bash
# 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 # Pages 1-5
qpdf
bash
# 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 # Rotate page 1 by 90 degrees # Remove password qpdf --password=mypassword --decrypt encrypted.pdf decrypted.pdf
pdftk (if available)
bash
# 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
python
# Requires: pip install pytesseract pdf2image
import pytesseract
from pdf2image import convert_from_path
# Convert PDF to images
images = convert_from_path('scanned.pdf')
# OCR each page
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
python
from pypdf import PdfReader, PdfWriter
# Create watermark (or load existing)
watermark = PdfReader("watermark.pdf").pages[0]
# Apply to all pages
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
bash
# Using pdfimages (poppler-utils) pdfimages -j input.pdf output_prefix # This extracts all images as output_prefix-000.jpg, output_prefix-001.jpg, etc.
Password Protection
python
from pypdf import PdfReader, PdfWriter
reader = PdfReader("input.pdf")
writer = PdfWriter()
for page in reader.pages:
writer.add_page(page)
# Add password
writer.encrypt("userpassword", "ownerpassword")
with open("encrypted.pdf", "wb") as output:
writer.write(output)
Quick Reference
| Task | Best Tool | Command/Code |
|---|---|---|
| Merge PDFs | pypdf | writer.add_page(page) |
| Split PDFs | pypdf | One page per file |
| Extract text | pdfplumber | page.extract_text() |
| Extract tables | pdfplumber | page.extract_tables() |
| Create PDFs | reportlab | Canvas or Platypus |
| Command line merge | qpdf | qpdf --empty --pages ... |
| OCR scanned PDFs | pytesseract | Convert to image first |
| Fill PDF forms | pdf-lib or pypdf (see forms.md) | See forms.md |
Next Steps
- •For advanced pypdfium2 usage, see reference.md
- •For JavaScript libraries (pdf-lib), see reference.md
- •If you need to fill out a PDF form, follow the instructions in forms.md
- •For troubleshooting guides, see reference.md