AVIF 无损 vs 有损 2026：何时使用？ [指南]

Compression Modes Explained

AVIF supports both lossless and lossy compression, each with distinct characteristics.

• Lossless Compression: Preserves every pixel exactly. Original data can be perfectly reconstructed. Typical compression: 20-40% size reduction.
• Lossy Compression: Discards imperceptible data for dramatic size reduction. One-way process—original cannot be recovered. Typical compression: 70-95% size reduction.
• Near-Lossless: Minimal, visually imperceptible loss for better compression than true lossless. Often the sweet spot for many applications.

When to Use Lossless

Lossless compression is essential in specific scenarios.

• Medical Imaging: Diagnostic accuracy requires perfect pixel preservation. No compression artifacts allowed.
• Archival Storage: Master files for long-term preservation. Lossy re-compression over time causes generational loss.
• Source Files for Editing: Images that will undergo further editing should remain lossless to prevent artifact accumulation.
• Text and Line Art: Sharp edges in screenshots, diagrams, and text are prone to visible lossy artifacts.
• Legal Documents: Scanned documents where pixel accuracy has legal implications.

Lossy Best Practices

For most web and general-purpose use, lossy compression provides the best balance.

Quality perception varies by content type. Photographs tolerate more compression than graphics with sharp edges. Test with representative samples to find optimal settings for your specific content.

Hybrid Approaches

Advanced workflows combine both modes strategically.

Store masters in lossless AVIF, generate lossy derivatives for distribution. This preserves quality for future needs while optimizing delivery. The lossless master ensures you can always regenerate better lossy versions as encoding improves.

Some encoders support lossless alpha with lossy color—perfect for transparent images where edge quality matters but interior compression is acceptable.

# FFmpeg: Lossless AVIF master
ffmpeg -i input.png -c:v libaom-av1 -lossless 1 master.avif

# Generate lossy web version from master
ffmpeg -i master.avif -c:v libaom-av1 -crf 30 web.avif