Claude-skill-registry-data merge-book-cover

Merge a cover image into a PDF book while preserving aspect ratio and matching width. Use when the user wants to "merge cover", "combine pdf", "fix cover size", or "add cover image".

install

source · Clone the upstream repo

git clone https://github.com/majiayu000/claude-skill-registry-data

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/majiayu000/claude-skill-registry-data "$T" && mkdir -p ~/.claude/skills && cp -r "$T/data/merge-book-cover" ~/.claude/skills/majiayu000-claude-skill-registry-data-merge-book-cover && rm -rf "$T"

manifest: data/merge-book-cover/SKILL.md

source content

PDF Cover Merger

Merges a cover image (PNG/JPG) into an existing PDF book, ensuring the cover matches the book's page width exactly while preserving its aspect ratio.

Why? Solving the problem of misaligned or distorted cover pages when combining images with PDF documents programmatically.

Quick Start

Ensure
```
assets/cover.png
```
exists.
Ensure
```
docs/Data-Science-with-Python.pdf
```
exists.

Run the script:

python3 .agent/skills/merge-book-cover/scripts/merge_cover.py

Prerequisites

Python 3
Packages:
```
img2pdf
```
,
```
pikepdf
```
,
```
Pillow
```

Workflow Steps

1. Install Dependencies

Ensure the required Python packages are installed.

python3 -m pip install img2pdf pikepdf Pillow

2. Verify Files

Ensure the source files are in place:

Cover Image:
```
assets/cover.png
```
Book PDF:
```
docs/Data-Science-with-Python.pdf
```

3. Run Merge Script

Execute the script to resize the cover and merge it.

python3 .agent/skills/merge-book-cover/scripts/merge_cover.py

[!TIP] The script automatically detects the width of the book's first page and scales the cover to match it perfectly, avoiding white margins or distortion.

4. Verify Output

Check the output file:

docs/Data-Science-with-Python_FINAL.pdf

Troubleshooting

Problem Cause Solution

ModuleNotFoundError

Missing Python packages

Run

python3 -m pip install ...

FileNotFoundError

Missing cover or book PDF

check paths

assets/cover.png

and

docs/...

| Aspect Ratio issues | N/A | Script auto-calculates height based on width. |

Quality Rules

Zero Distortion: The cover image must perfectly maintain its original aspect ratio.
Exact Width Match: The cover page width must exactly match the book's first page width (usually 612 pts for Letter).
No Margins: There should be no white bars or margins around the cover.
Automation: The process must run without manual image editing.

Testing & Evaluation

Manual Validation

Run the script:

python3 .agent/skills/merge-book-cover/scripts/merge_cover.py

Open
```
docs/Data-Science-with-Python_FINAL.pdf
```
.
Check 1: Is the cover (Page 1) flush with the edges? (No white border)
Check 2: Does Page 2 (Title Page) have the exact same width as Page 1?
Check 3: Is the cover image undistorted (circles are circular, text is proportional)?