Optimize JPEG

Squeeze JPEG file size. Two modes:

• lossless (default) — jpegoptim --strip-all. Repacks Huffman tables and strips metadata. No re-encode, no quality change.
• recompress — mozjpeg (cjpeg-mozjpeg). Re-encodes with better quantisation tables; 10–15% smaller than libjpeg-turbo for the same SSIM. Quality flag controls trade-off.

When to use

• Web-prep: photo galleries, blog images, anything destined for upload.
• Archive squeeze: lossless mode is the no-regret option for any JPEG-heavy folder.
• Pre-step inside web-ready orchestrator.

Do not use this skill when:

• Source is PNG → use optimize-png.
• Source is HEIC/RAW/TIFF — pipe through web-ready (or convert first).
• The JPEG is already heavily compressed (<70% quality estimate) — recompress will visibly degrade.

Inputs