Imagemagick Expert

ImageMagick CLIを使用した画像処理の専門家スキル。フォーマット変換、リサイズ、トリミング、回転、フィルタ適用、アニメーションGIF作成、PDF処理、バッチ処理を支援。Use when processing images via CLI, converting formats, resizing, cropping, applying filters, creating animations, or batch processing images.

No API Required

Download Skill Package (.skill) View Source on GitHub

Table of Contents

1. Overview

ImageMagickは画像の作成、編集、合成、変換を行うための強力なCLIツールセットです。200以上の画像フォーマットをサポートし、リサイズ、回転、トリミング、色調整、フィルタ適用、アニメーション作成など幅広い画像処理が可能です。

Primary Commands

Command Purpose Example
magick メインコマンド（v7+）、画像変換・処理 magick input.png output.jpg
convert 画像変換・処理（レガシー、v6互換） convert input.png output.jpg
identify 画像情報の取得 identify -verbose image.png
mogrify 画像のインプレース変換 mogrify -resize 50% *.jpg
composite 画像の合成 composite overlay.png base.png result.png
montage 複数画像のモンタージュ作成 montage *.jpg -tile 3x3 montage.jpg

2. Prerequisites 

# Check installation
magick --version

# macOS (Homebrew)
brew install imagemagick

# Linux (Ubuntu/Debian)
sudo apt-get install imagemagick

# Linux (CentOS/RHEL)
sudo yum install ImageMagick

3. Quick Start

  1. Identify Requirements - Determine the desired operation (convert, resize, filter, etc.) and output format
  2. Select Command - Choose appropriate ImageMagick command (magick, mogrify, identify, etc.)
  3. Build Command - Construct command with options and parameters based on Core Operations examples
  4. Execute - Run the command via Bash tool
  5. Verify Output - Check the result using identify or visual inspection
  6. Iterate - Adjust parameters if needed based on output quality

4. How It Works

  1. Identify Requirements - Determine the desired operation (convert, resize, filter, etc.) and output format
  2. Select Command - Choose appropriate ImageMagick command (magick, mogrify, identify, etc.)
  3. Build Command - Construct command with options and parameters based on Core Operations examples
  4. Execute - Run the command via Bash tool
  5. Verify Output - Check the result using identify or visual inspection
  6. Iterate - Adjust parameters if needed based on output quality

For batch operations, use mogrify for in-place edits or shell loops for custom naming patterns.

5. Usage Examples

  • 画像フォーマットの変換（PNG↔JPEG↔WebP↔GIF等）
  • 画像のリサイズ、トリミング、回転
  • バッチ処理で複数画像を一括変換
  • 画像へのエフェクト・フィルタ適用
  • アニメーションGIFの作成・編集
  • PDF↔画像の相互変換

6. Understanding the Output

This skill provides conversational guidance and ImageMagick CLI command examples. No files are automatically generated - you execute the suggested commands via the Bash tool to process images according to your requirements.

7. Tips & Best Practices

  • Begin with the smallest realistic sample input so you can validate the workflow before scaling up.
  • Keep skills/imagemagick-expert/SKILL.md open while working; it remains the authoritative source for the full procedure.
  • Review the most relevant reference files first instead of scanning every guide: batch_processing.md, image_manipulation.md, format_conversion.md.
  • Preserve intermediate outputs so you can explain assumptions, diffs, and follow-up actions clearly.

8. Combining with Other Skills

  • Combine this skill with adjacent skills in the same category when the work spans planning, implementation, and review.
  • Browse the broader category for neighboring workflows: category index.
  • Use the English skill catalog when you need to chain this workflow into a larger end-to-end process.

9. Troubleshooting

  • Re-check prerequisites first: missing runtime dependencies and unsupported file formats are the most common failures.
  • If a helper script is involved, run it with a minimal sample input before applying it to a full dataset or repository.
  • Compare your input shape against the reference files to confirm expected fields, sections, or metadata are present.

10. Reference

References:

  • skills/imagemagick-expert/references/batch_processing.md
  • skills/imagemagick-expert/references/format_conversion.md
  • skills/imagemagick-expert/references/image_manipulation.md