Mp4 To Gif

Use when the user wants to convert MP4 video files to GIF format, or asks about video-to-GIF conversion with quality/size control

MP4 to GIF Conversion

Overview

Convert MP4 videos to high-quality GIFs using ffmpeg's two-pass palette method. The two-pass approach produces significantly better color quality than direct conversion.

When to Use

• User wants to convert MP4 (or other video) to GIF
• User needs to create GIFs from video for documentation, demos, or sharing
• User asks about reducing GIF file size or improving GIF quality

Prerequisites

• ffmpeg must be installed and available in PATH

Core Method

Two-pass palette-based conversion (always use this over single-pass):

# Pass 1: Generate optimized palette
ffmpeg -y -i <input> -vf "fps=15,scale=480:-1:flags=lanczos,palettegen=stats_mode=diff" /tmp/palette.png

# Pass 2: Convert using palette
ffmpeg -y -i <input> -i /tmp/palette.png -lavfi "fps=15,scale=480:-1:flags=lanczos [x]; [x][1:v] paletteuse=dither=bayer:bayer_scale=5:diff_mode=rectangle" <output>

Quick Reference

Parameter	Default	Effect
fps	15	Frame rate — lower = smaller file, choppier motion
scale width	480	Output width in px — height auto-calculated (-1)
lanczos	—	High-quality downscaling filter
stats_mode=diff	—	Palette optimized for frame differences (better for motion)
dither=bayer	—	Ordered dithering, good balance of quality/size
bayer_scale	5	Dither strength (0-5), higher = more dithering
diff_mode=rectangle	—	Only update changed regions (smaller file)

Size vs Quality Tradeoffs

Goal	Adjust
Smaller file	Lower fps (10), smaller width (320), or trim duration
Smoother motion	Higher fps (24-30), but file size increases significantly
Better colors	Use stats_mode=full for static/slow content
Sharper	Increase width (640-800), costs more file size

Bundled Scripts

Two scripts are bundled alongside this SKILL.md. Use the one matching the current platform.

Windows (PowerShell) — mp4_to_gif.ps1:

& "<this-skill-dir>/mp4_to_gif.ps1" -InputFile <input>                    # Defaults: 480px, 15fps
& "<this-skill-dir>/mp4_to_gif.ps1" -InputFile <input> -Width 640 -Fps 20 # Custom settings
& "<this-skill-dir>/mp4_to_gif.ps1" -InputFile <input> -OutputFile <output> # Custom output name

Linux / macOS (Bash) — mp4_to_gif.sh:

bash "<this-skill-dir>/mp4_to_gif.sh" -i <input>                    # Defaults: 480px, 15fps
bash "<this-skill-dir>/mp4_to_gif.sh" -i <input> -w 640 -f 20      # Custom settings
bash "<this-skill-dir>/mp4_to_gif.sh" -i <input> -o <output>        # Custom output name

When Claude invokes this skill, resolve <this-skill-dir> to the absolute path of the directory containing this SKILL.md.

Common Mistakes

• Single-pass conversion (ffmpeg -i in.mp4 out.gif) — produces terrible banding and color artifacts. Always use the two-pass palette method.
• Too high fps — 30fps GIFs are massive. 15fps is usually sufficient for demos.
• Too wide — 480px is good for most uses. Full 1080p GIFs are impractically large.
• Forgetting to clean up palette — Delete the temporary palette.png after conversion.