Output files and metadata

Cache-file ownership

Successful compression creates a new local cache file and returns its URI. The source is not modified.

• Treat the returned URI as temporary.
• Upload, copy, or move an output that must outlive normal cache cleanup.
• Delete outputs when the application no longer needs them.
• Do not assume a cache URI survives an OS cleanup, app reinstall, or device migration.
• The package does not maintain a global output registry or delete old files on your behalf.

Metadata policies

Policy	Behavior
safe	Default. Avoids forwarding privacy-sensitive source metadata. Android copies a filtered JPEG EXIF allowlist; iOS re-encodes without source metadata.
strip	Re-encodes without copying source metadata.
preserve	Supported only for JPEG source to JPEG output. Orientation is rendered into pixels and normalized.

The application remains responsible for its own consent, retention, upload, and privacy disclosures. Verify output metadata if legal or product policy requires stronger guarantees than the package contract.

Byte metrics

• originalByteSize is the native-readable source byte count.
• byteSize is the encoded output byte count.
• compressionRatio is byteSize / originalByteSize.

Pixel dimensions and byte size answer different questions; resizing can reduce both, while a format-only conversion may produce a larger output.