Crate gamut_webp 

WebP image encoder and decoder — an intra-frame VP8/VP8L still-image bitstream wrapped in a RIFF container.

The public surface mirrors gamut-avif: a WebpEncoder implementing gamut_core::EncodeImage and a WebpDecoder implementing gamut_core::DecodeImage. The container layer is gamut_riff; the codec layer is the vp8l (lossless, RFC 9649 §3) and vp8 (lossy intra, RFC 6386) module trees, whose modules each cite the spec section they implement. The implementation status and milestones are tracked in STATUS.md.

gamut is image-first, so only the intra/key-frame still-image subset of VP8 is in scope (no inter-frame prediction, motion, or sequences). Both codecs are fully implemented, for Rgb8 and Rgba8 input: VP8L lossless (every transform, LZ77, the color cache, meta prefix codes) and VP8 lossy key-frame intra (DC/V/H/TM and per-4×4 B_PRED prediction, the simple and normal loop filters, segmentation, 1/2/4/8 token partitions, and skip). Transparent lossy images use the extended (VP8X) container with an ALPH alpha chunk. Every component is validated against libwebp as an oracle in both directions (bit-exact at the YUV-plane level for lossy), plus a malformed-input robustness corpus.

Modules

alpha

The WebP ALPH alpha chunk (RFC 9649 §2.7.1): an 8-bit transparency plane stored alongside a lossy VP8 bitstream in an extended (VP8X) file.

vp8

VP8 — the lossy still-image (key-frame intra) bitstream (RFC 6386).

vp8l

VP8L — the WebP lossless still-image bitstream (RFC 9649 §3).

Structs

Dimensions

Width and height of an image, in pixels.

WebpConfig

Configuration for a WebpEncoder.

WebpDecoder

Decodes a WebP file to interleaved 8-bit RGB.

WebpEncoder

Encodes 8-bit RGB images to WebP.

Enums

WebpMode

Which WebP bitstream the encoder produces.