A-PDF

A-PDF is a fast, command-line tool designed to replace Unicode and Hex text directly within PDF content streams.

Features

• Direct Stream Replacement: Modifies the underlying PDF streams directly for fast and precise text replacement.
• Unicode & Hex Support: Replace text using standard string replacements that are automatically encoded to the document's fonts.
• Spacing Compensation: Automatically compensates for TJ (Text Justification) width adjustments after text replacements to preserve document layout (can be disabled).
• Strict Mode: Optionally fail replacements if text is missing or the font cannot encode the requested characters.
• Fallback Font Support: Embed a custom TrueType font when the PDF's subset font lacks a glyph, or disable fallback entirely.
• Page Selection: Select specific pages to process.

Installation

You can run the tool directly using uv, which will automatically handle dependencies:

uv add apdf # or As a tool: uv tool install apdf
# then Run it
uv run apdf --help

Or simply use it in your standard Python environment.

pip install apdf

# Run 
apdf --help

Usage As Library

from apdf import replace_pdf_text_detailed

rep = replace_pdf_text_detailed(
    input_pdf="Test1.pdf",
    output_pdf="Test1_out.pdf",
    replacements={
        "Old Text": "New Text",
        # "Hello": "World",
        # "2026": "2027", 
    },

    # Optional parameters:
    #pages={2, 3, 4},       # Only these pages
    # pages=2,             # Only page 2
    # pages=range(1, 6),   # Pages 1 through 5
    # pages=None,          # All pages (default)

    # fallback_font="FONT.ttf",
    # font_fallback=True,
    # strict=True,
)

print("Replacements:", rep.replacements)
print("Changed streams:", rep.changed_streams)
print("Scanned streams:", rep.scanned_streams)
print("Missing:", rep.missing)
print("Encoding failures:", rep.encoding_failures)

Usage As CLI Tool

apdf [-h] [-r OLD=NEW] [-nopa] [-s] [-ff FONT.ttf] [-no-ff] [-p PAGELIST] input [output]

Examples

Basic replacement:

apdf input.pdf output.pdf -r "OldText=NewText"

Multiple replacements:

apdf document.pdf updated_document.pdf \
    -r "Draft=Final" \
    -r "2023=2024"

Disable width compensation (if characters are bunching up or spacing is incorrect):

apdf input.pdf output.pdf -r "foo=bar" -nopa

Strict mode (fails if the replacement target is not found):

apdf input.pdf output.pdf -r "foo=bar" -s

Arguments

• input: The source PDF file.
• output: (Optional) The destination PDF file. Defaults to output.pdf.
• -r OLD=NEW: Replace. The text replacement pair. You can supply this argument multiple times.
• -p 2, -p 2,3,4, or -p 1-5 to edit only selected pages. Without -p, all pages are processed.
• -nopa: No preserve advance. Do not compensate TJ text widths after making replacements.
• -s: Strict. Fail if the original text is missing or the selected font cannot encode the new text.
• -ff FONT.ttf: Fallback font. TrueType font to embed when the PDF's subset font lacks a glyph.
• -no-ff: No font fallback. Reject missing glyphs instead of embedding a fallback font.