PDF Processing Guide

Overview

Essential PDF processing operations using Python libraries and command-line tools. For advanced features, JavaScript libraries, and detailed examples, see reference.md. For filling PDF forms, read forms.md and follow its instructions.

Quick Start

from pypdf import PdfReader, PdfWriter

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

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}")

Rotate Pages

reader = PdfReader("input.pdf") writer = PdfWriter() page = reader.pages[0] page.rotate(90) 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

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.line(100, height - 140, 400, height - 140) c.save()

Multi-Page with Platypus

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 = []

story.append(Paragraph("Report Title", styles['Title'])) story.append(Spacer(1, 12)) story.append(Paragraph("This is the body of the report. " * 20, styles['Normal'])) story.append(PageBreak()) story.append(Paragraph("Page 2", styles['Heading1']))

doc.build(story)

Subscripts and Superscripts

IMPORTANT: Never use Unicode subscript/superscript characters 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:

from reportlab.platypus import Paragraph from reportlab.lib.styles import getSampleStyleSheet styles = getSampleStyleSheet()

chemical = Paragraph("H₂O", styles['Normal']) squared = Paragraph("x<super>2</super> + y<super>2</super>", styles['Normal'])

Command-Line Tools

pdftotext (poppler-utils)

pdftotext input.pdf output.txt pdftotext -layout input.pdf output.txt pdftotext -f 1 -l 5 input.pdf output.txt

qpdf

qpdf --empty --pages file1.pdf file2.pdf -- merged.pdf qpdf input.pdf --pages . 1-5 -- pages1-5.pdf qpdf input.pdf output.pdf --rotate=+90:1 qpdf --password=mypassword --decrypt encrypted.pdf decrypted.pdf

Common Tasks

OCR Scanned PDFs

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"

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

pdfimages -j input.pdf output_prefix

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)

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 pypdf or pdf-lib See forms.md

Next Steps

• For advanced pypdfium2 usage, see reference.md

• For JavaScript libraries (pdf-lib), see reference.md

• For filling PDF forms, follow instructions in forms.md