webpkit

A pure-Rust WebP codec — lossless (VP8L) and lossy (VP8), decode and encode, behind one API. This is the recommended entry point.

Part of the webpkit workspace.

One-call helpers cover the common case — raw RGBA8 in, WebP bytes out (and back):

use webpkit::{decode_rgba, encode_lossless_rgba, encode_lossy_rgba};

fn convert(width: u32, height: u32, rgba: &[u8]) -> webpkit::Result<()> {
    // Encode raw RGBA8 pixels — lossless (byte-exact) or lossy at a quality.
    let lossless = encode_lossless_rgba(width, height, rgba)?;
    let _lossy = encode_lossy_rgba(width, height, rgba, 90)?;

    // Decode any WebP (lossless or lossy) straight back to pixels.
    let (_dims, _pixels) = decode_rgba(&lossless)?;
    Ok(())
}

For metadata preservation, effort tiers, non-RGBA layouts, or streaming, reach for the decode function and the type-state Encoder builder:

use webpkit::{decode, Effort, Encoder};

fn reencode(bytes: &[u8]) -> webpkit::Result<()> {
    let img = decode(bytes)?; // -> Image (keeps ICC/Exif/XMP metadata)
    let _lossless = Encoder::lossless().effort(Effort::Best).encode(&img)?;
    let _lossy = Encoder::lossy().quality(90).encode(&img)?;
    Ok(())
}

See examples/roundtrip.rs for a complete, runnable encode → decode round-trip.

decode is safe on untrusted input by default: it caps the canvas at DEFAULT_MAX_PIXELS before allocating, so a hostile header cannot exhaust memory. Use decode_with + DecodeOptions::max_pixels for a different cap, or DecodeOptions::unbounded to lift it for trusted input.

Optional features

Off by default, so a plain dependency stays zero-dependency:

• rayon — encoder data-parallelism (byte-identical output, only faster).
• image — TryFrom conversions between image::DynamicImage/RgbaImage and the codec's Image.

License

Dual-licensed under MIT OR Apache-2.0.